Book IV

., ch. xvii., §§ 2 and 3) comes to the special explanation of reason he entirely loses sight of this simple, primary characteristic, and he also falls into a wavering, undetermined, incomplete account of mangled and derivative manifestations of it. Leibnitz also, in the corresponding part of his work, behaves in a similar manner, only with more confusion and indistinctness. In the Appendix, I have fully considered how Kant confused and falsified the conception of the nature of reason. But whoever will take the trouble to go through in this reference the mass of philosophical writing which has appeared since Kant, will find out, that just as the faults of princes must be expiated by whole nations, the errors of great minds extend their influence over whole generations, and even over centuries; they grow and propagate themselves, and finally degenerate into monstrosities. All this arises from the fact that, as Berkeley says, “Few men think; yet all will have opinions.”

The understanding has only one function—immediate knowledge of the relation of cause and effect. Yet the perception of the real world, and all common sense, sagacity, and inventiveness, however multifarious their applications may be, are quite clearly seen to be nothing more than manifestations of that one function. So also the reason has one function; and from it all the manifestations of reason we have mentioned, which distinguish the life of man from that of the brutes, may easily be explained. The application or the non-application of this function is all that is meant by what men have everywhere and always called rational and irrational.(12)

§ 9. Concepts form a distinct class of ideas, existing only in the mind of man, and entirely different from the ideas of perception which we have considered up till now. We can therefore never attain to a sensuous and, properly speaking, evident knowledge of their nature, but only to a knowledge which is abstract and discursive. It would, therefore, be absurd to demand that they should be verified in experience, if by experience is meant the real external world, which consists of ideas of perception, or that they should be brought before the eyes or the imagination like objects of perception. They can only be thought, not perceived, and only the effects which men accomplish through them are properly objects of experience. Such effects are language, preconceived and planned action and science, and all that results from these. Speech, as an object of outer experience, is obviously nothing more than a very complete telegraph, which communicates arbitrary signs with the greatest rapidity and the finest distinctions of difference. But what do these signs mean? How are they interpreted? When some one speaks, do we at once translate his words into pictures of the fancy, which instantaneously flash upon us, arrange and link themselves together, and assume form and colour according to the words that are poured forth, and their grammatical inflections? What a tumult there would be in our brains while we listened to a speech, or to the reading of a book? But what actually happens is not this at all. The meaning of a speech is, as a rule, immediately grasped, accurately and distinctly taken in, without the imagination being brought into play. It is reason which speaks to reason, keeping within its own province. It communicates and receives abstract conceptions, ideas that cannot be presented in perceptions, which are framed once for all, and are relatively few in number, but which yet encompass, contain, and represent all the innumerable objects of the actual world. This itself is sufficient to prove that the lower animals can never learn to speak or comprehend, although they have the organs of speech and ideas of perception in common with us. But because words represent this perfectly distinct class of ideas, whose subjective correlative is reason, they are without sense and meaning for the brutes. Thus language, like every other manifestation which we ascribe to reason, and like everything which distinguishes man from the brutes, is to be explained from this as its one simple source—conceptions, abstract ideas which cannot be presented in perception, but are general, and have no individual existence in space and time. Only in single cases do we pass from the conception to the perception, do we construct images as _representatives of concepts_ in perception, to which, however, they are never adequate. These cases are fully discussed in the essay on the principle of sufficient reason, § 28, and therefore I shall not repeat my explanation here. It may be compared, however, with what is said by Hume in the twelfth of his “Philosophical Essays,” p. 244, and by Herder in the “Metacritik,” pt. i. p. 274 (an otherwise worthless book). The Platonic idea, the possibility of which depends upon the union of imagination and reason, is the principal subject of the third book of this work.

Although concepts are fundamentally different from ideas of perception, they stand in a necessary relation to them, without which they would be nothing. This relation therefore constitutes the whole nature and existence of concepts. Reflection is the necessary copy or repetition of the originally presented world of perception, but it is a special kind of copy in an entirely different material. Thus concepts may quite properly be called ideas of ideas. The principle of sufficient reason has here also a special form. Now we have seen that the form under which the principle of sufficient reason appears in a class of ideas always constitutes and exhausts the whole nature of the class, so far as it consists of ideas, so that time is throughout succession, and nothing more; space is throughout position, and nothing more; matter is throughout causation, and nothing more. In the same way the whole nature of concepts, or the class of abstract ideas, consists simply in the relation which the principle of sufficient reason expresses in them; and as this is the relation to the ground of knowledge, the whole nature of the abstract idea is simply and solely its relation to another idea, which is its ground of knowledge. This, indeed, may, in the first instance, be a concept, an abstract idea, and this again may have only a similar abstract ground of knowledge; but the chain of grounds of knowledge does not extend _ad infinitum_; it must end at last in a concept which has its ground in knowledge of perception; for the whole world of reflection rests on the world of perception as its ground of knowledge. Hence the class of abstract ideas is in this respect distinguished from other classes; in the latter the principle of sufficient reason always demands merely a relation to another idea of the _same_ class, but in the case of abstract ideas, it at last demands a relation to an idea of _another_ class.

Those concepts which, as has just been pointed out, are not immediately related to the world of perception, but only through the medium of one, or it may be several other concepts, have been called by preference _abstracta_, and those which have their ground immediately in the world of perception have been called _concreta_. But this last name is only loosely applicable to the concepts denoted by it, for they are always merely _abstracta_, and not ideas of perception. These names, which have originated in a very dim consciousness of the distinctions they imply, may yet, with this explanation, be retained. As examples of the first kind of concepts, _i.e._, _abstracta_ in the fullest sense, we may take “relation,” “virtue,” “investigation,” “beginning,” and so on. As examples of the second kind, loosely called _concreta_, we may take such concepts as “man,” “stone,” “horse,” &c. If it were not a somewhat too pictorial and therefore absurd simile, we might very appropriately call the latter the ground floor, and the former the upper stories of the building of reflection.(13)

It is not, as is commonly supposed, an essential characteristic of a concept that it should contain much under it, that is to say, that many ideas of perception, or it may be other abstract ideas, should stand to it in the relation of its ground of knowledge, _i.e._, be thought through it. This is merely a derived and secondary characteristic, and, as a matter of fact, does not always exist, though it must always exist potentially. This characteristic arises from the fact that a concept is an idea of an idea, _i.e._, its whole nature consists in its relation to another idea; but as it is not this idea itself, which is generally an idea of perception and therefore belongs to quite a different class, the latter may have temporal, spacial, and other determinations, and in general many relations which are not thought along with it in the concept. Thus we see that several ideas which are different in unessential particulars may be thought by means of one concept, _i.e._, may be brought under it. Yet this power of embracing several things is not an essential but merely an accidental characteristic of the concept. There may be concepts through which only one real object is thought, but which are nevertheless abstract and general, by no means capable of presentation individually and as perceptions. Such, for example, is the conception which any one may have of a particular town which he only knows from geography; although only this one town is thought under it, it might yet be applied to several towns differing in certain respects. We see then that a concept is not general because of being abstracted from several objects; but conversely, because generality, that is to say, non-determination of the particular, belongs to the concept as an abstract idea of the reason, different things can be thought by means of the same one.

It follows from what has been said that every concept, just because it is abstract and incapable of presentation in perception, and is therefore not a completely determined idea, has what is called extension or sphere, even in the case in which only one real object exists that corresponds to it. Now we always find that the sphere of one concept has something in common with the sphere of other concepts. That is to say, part of what is thought under one concept is the same as what is thought under other concepts; and conversely, part of what is thought under these concepts is the same as what is thought under the first; although, if they are really different concepts, each of them, or at least one of them, contains something which the other does not contain; this is the relation in which every subject stands to its predicate. The recognition of this relation is called judgment. The representation of these spheres by means of figures in space, is an exceedingly happy idea. It first occurred to Gottfried Plouquet, who used squares for the purpose. Lambert, although later than him, used only lines, which he placed under each other. Euler carried out the idea completely with circles. Upon what this complete analogy between the relations of concepts, and those of figures in space, ultimately rests, I am unable to say. It is, however, a very fortunate circumstance for logic that all the relations of concepts, according to their possibility, _i.e._, _a priori_, may be made plain in perception by the use of such figures, in the following way:—

(1.) The spheres of two concepts coincide: for example the concept of necessity and the concept of following from given grounds, in the same way the concepts of _Ruminantia_ and _Bisulca_ (ruminating and cloven-hoofed animals), also those of vertebrate and red-blooded animals (although there might be some doubt about this on account of the annelida): they are convertible concepts. Such concepts are represented by a single circle which stands for either of them.

(2.) The sphere of one concept includes that of the other.

[Illustration: Category "horse" within category "animal".]

(3.) A sphere includes two or more spheres which exclude each other and fill it.

[Illustration: Circle divided into thirds "right", "acute", and "obtuse".]

(4.) Two spheres include each a part of the other.

[Illustration: Two overlapping circles, one "flower" and one "red".]

(5.) Two spheres lie in a third, but do not fill it.

[Illustration: A large circle, "matter", within which are two other circles, "water" and "earth".]

This last case applies to all concepts whose spheres have nothing immediately in common, for there is always a third sphere, often a much wider one, which includes both.

To these cases all combinations of concepts may be referred, and from them the entire doctrine of the judgment, its conversion, contraposition, equipollence, disjunction (this according to the third figure) may be deduced. From these also may be derived the properties of the judgment, upon which Kant based his pretended categories of the understanding, with the exception however of the hypothetical form, which is not a combination of concepts, but of judgments. A full account is given in the Appendix of “Modality,” and indeed of every property of judgments on which the categories are founded.

With regard to the possible combinations of concepts which we have given, it has only further to be remarked that they may also be combined with each other in many ways. For example, the fourth figure with the second. Only if one sphere, which partly or wholly contains another, is itself contained in a third sphere, do these together exemplify the syllogism in the first figure, _i.e._, that combination of judgments, by means of which it is known that a concept which is partly or wholly contained in another concept, is also contained in a third concept, which again contains the first: and also, conversely, the negation; the pictorial representation of which can, of course, only be two connected spheres which do not lie within a third sphere. If many spheres are brought together in this way we get a long train of syllogisms. This schematism of concepts, which has already been fairly well explained in more than one textbook, may be used as the foundation of the doctrine of the judgment, and indeed of the whole syllogistic theory, and in this way the treatment of both becomes very easy and simple. Because, through it, all syllogistic rules may be seen in their origin, and may be deduced and explained. It is not necessary, however, to load the memory with these rules, as logic is never of practical use, but has only a theoretical interest for philosophy. For although it may be said that logic is related to rational thinking as thorough-bass is to music, or less exactly, as ethics is to virtue, or æsthetics to art; we must yet remember that no one ever became an artist by the study of æsthetics; that a noble character was never formed by the study of ethics; that long before Rameau, men composed correctly and beautifully, and that we do not need to know thorough-bass in order to detect discords: and just as little do we need to know logic in order to avoid being misled by fallacies. Yet it must be conceded that thorough-bass is of the greatest use in the practice of musical composition, although it may not be necessary for the understanding of it; and indeed æsthetics and even ethics, though in a much less degree, and for the most part negatively, may be of some use in practice, so that we cannot deny them all practical worth, but of logic even this much cannot be conceded. It is nothing more than the knowledge in the abstract of what every one knows in the concrete. Therefore we call in the aid of logical rules, just as little to enable us to construct a correct argument as to prevent us from consenting to a false one, and the most learned logician lays aside the rules of logic altogether in his actual thought. This may be explained in the following way. Every science is a system of general and therefore abstract truths, laws, and rules with reference to a special class of objects. The individual case coming under these laws is determined in accordance with this general knowledge, which is valid once for all; because such application of the general principle is far easier than the exhaustive investigation of the particular case; for the general abstract knowledge which has once been obtained is always more within our reach than the empirical investigation of the particular case. With logic, however, it is just the other way. It is the general knowledge of the mode of procedure of the reason expressed in the form of rules. It is reached by the introspection of reason, and by abstraction from all content. But this mode of procedure is necessary and essential to reason, so that it will never depart from it if left to itself. It is, therefore, easier and surer to let it proceed itself according to its nature in each particular case, than to present to it the knowledge abstracted from this procedure in the form of a foreign and externally given law. It is easier, because, while in the case of all other sciences, the general rule is more within our reach than the investigation of the particular case taken by itself; with the use of reason, on the contrary, its necessary procedure in a given case is always more within our reach than the general rule abstracted from it; for that which thinks in us is reason itself. It is surer, because a mistake may more easily occur in such abstract knowledge, or in its application, than that a process of reason should take place which would run contrary to its essence and nature. Hence arises the remarkable fact, that while in other sciences the particular case is always proved by the rule, in logic, on the contrary, the rule must always be proved from the particular case; and even the most practised logician, if he remark that in some particular case he concludes otherwise than the rule prescribes, will always expect to find a mistake in the rule rather than in his own conclusion. To desire to make practical use of logic means, therefore, to desire to derive with unspeakable trouble, from general rules, that which is immediately known with the greatest certainty in the particular case. It is just as if a man were to consult mechanics as to the motion of his body, and physiology as to his digestion; and whoever has learnt logic for practical purposes is like him who would teach a beaver to make its own dam. Logic is, therefore, without practical utility; but it must nevertheless be retained, because it has philosophical interest as the special knowledge of the organisation and

## action of reason. It is rightly regarded as a definite, self-subsisting,

self-contained, complete, and thoroughly safe discipline; to be treated scientifically for itself alone and independently of everything else, and therefore to be studied at the universities. But it has its real value, in relation to philosophy as a whole, in the inquiry into the nature of knowledge, and indeed of rational and abstract knowledge. Therefore the exposition of logic should not have so much the form of a practical science, should not contain merely naked arbitrary rules for the correct formation of the judgment, the syllogism, &c., but should rather be directed to the knowledge of the nature of reason and the concept, and to the detailed investigation of the principle of sufficient reason of knowing. For logic is only a paraphrase of this principle, and, more exactly, only of that exemplification of it in which the ground that gives truth to the judgment is neither empirical nor metaphysical, but logical or metalogical. Besides the principle of sufficient reason of knowing, it is necessary to take account of the three remaining fundamental laws of thought, or judgments of metalogical truth, so nearly related to it; and out of these the whole science of reason grows. The nature of thought proper, that is to say, of the judgment and the syllogism, must be exhibited in the combination of the spheres of concepts, according to the analogy of the special schema, in the way shown above; and from all this the rules of the judgment and the syllogism are to be deduced by construction. The only practical use we can make of logic is in a debate, when we can convict our antagonist of his intentional fallacies, rather than of his actual mistakes, by giving them their technical names. By thus throwing into the background the practical aim of logic, and bringing out its connection with the whole scheme of philosophy as one of its chapters, we do not think that we shall make the study of it less prevalent than it is just now. For at the present day every one who does not wish to remain uncultured, and to be numbered with the ignorant and incompetent multitude, must study speculative philosophy. For the nineteenth century is a philosophical age, though by this we do not mean either that it has philosophy, or that philosophy governs it, but rather that it is ripe for philosophy, and, therefore, stands in need of it. This is a sign of a high degree of civilisation, and indeed, is a definite stage in the culture of the ages.(14)

Though logic is of so little practical use, it cannot be denied that it was invented for practical purposes. It appears to me to have originated in the following way:—As the love of debating developed among the Eleatics, the Megarics, and the Sophists, and by degrees became almost a passion, the confusion in which nearly every debate ended must have made them feel the necessity of a method of procedure as a guide; and for this a scientific dialectic had to be sought. The first thing which would have to be observed would be that both the disputing parties should always be agreed on some one proposition, to which the disputed points might be referred. The beginning of the methodical procedure consisted in this, that the propositions admitted on both sides were formally stated to be so, and placed at the head of the inquiry. But these propositions were at first concerned only with the material of the inquiry. It was soon observed that in the process of going back to the truth admitted on both sides, and of deducing their assertions from it, each party followed certain forms and laws about which, without any express agreement, there was no difference of opinion. And from this it became evident that these must constitute the peculiar and natural procedure of reason itself, the form of investigation. Although this was not exposed to any doubt or difference of opinion, some pedantically systematic philosopher hit upon the idea that it would look well, and be the completion of the method of dialectic, if this formal part of all discussion, this regular procedure of reason itself, were to be expressed in abstract propositions, just like the substantial propositions admitted on both sides, and placed at the beginning of every investigation, as the fixed canon of debate to which reference and appeal must always be made. In this way what had formerly been followed only by tacit agreement, and instinctively, would be consciously recognised and formally expressed. By degrees, more or less perfect expressions were found for the fundamental principles of logic, such as the principles of contradiction, sufficient reason, excluded middle, the _dictum de omni et nullo_, as well as the special rules of the syllogism, as for example, _ex meris particularibus aut negativis nihil sequitur, a rationato ad rationem non valet consequentia_, and so on. That all this was only brought about slowly, and with great pains, and up till the time of Aristotle remained very incomplete, is evident from the awkward and tedious way in which logical truths are brought out in many of the Platonic dialogues, and still more from what Sextus Empiricus tells us of the controversies of the Megarics, about the easiest and simplest logical rules, and the laborious way in which they were brought into a definite form (Sext. Emp. adv. Math. l. 8, p. 112). But Aristotle collected, arranged, and corrected all that had been discovered before his time, and brought it to an incomparably greater state of perfection. If we thus observe how the course of Greek culture had prepared the way for, and led up to the work of Aristotle, we shall be little inclined to believe the assertion of the Persian author, quoted by Sir William Jones with much approval, that Kallisthenes found a complete system of logic among the Indians, and sent it to his uncle Aristotle (Asiatic Researches, vol. iv. p. 163). It is easy to understand that in the dreary middle ages the Aristotelian logic would be very acceptable to the controversial spirit of the schoolmen, which, in the absence of all real knowledge, spent its energy upon mere formulas and words, and that it would be eagerly adopted even in its mutilated Arabian form, and presently established as the centre of all knowledge. Though its authority has since declined, yet up to our own time logic has retained the credit of a self-contained, practical, and highly important science. Indeed, in our own day, the Kantian philosophy, the foundation-stone of which is taken from logic, has excited a new interest in it; which, in this respect, at any rate, that is, as the means of the knowledge of the nature of reason, it deserves.

Correct and accurate conclusions may be arrived at if we carefully observe the relation of the spheres of concepts, and only conclude that one sphere is contained in a third sphere, when we have clearly seen that this first sphere is contained in a second, which in its turn is contained in the third. On the other hand, the art of sophistry lies in casting only a superficial glance at the relations of the spheres of the concepts, and then manipulating these relations to suit our purposes, generally in the following way:—When the sphere of an observed concept lies partly within that of another concept, and partly within a third altogether different sphere, we treat it as if it lay entirely within the one or the other, as may suit our purpose. For example, in speaking of passion, we may subsume it under the concept of the greatest force, the mightiest agency in the world, or under the concept of the irrational, and this again under the concept of impotency or weakness. We may then repeat the process, and start anew with each concept to which the argument leads us. A concept has almost always several others, which partially come under it, and each of these contains part of the sphere of the first, but also includes in its own sphere something more, which is not in the first. But we draw attention only to that one of these latter concepts, under which we wish to subsume the first, and let the others remain unobserved, or keep them concealed. On the possession of this skill depends the whole art of sophistry and all finer fallacies; for logical fallacies such as _mentiens_, _velatus_, _cornatus_, &c., are clearly too clumsy for actual use. I am not aware that hitherto any one has traced the nature of all sophistry and persuasion back to this last possible ground of its existence, and referred it to the peculiar character of concepts, _i.e._, to the procedure of reason itself. Therefore, as my exposition has led me to it, though it is very easily understood, I will illustrate it in the following table by means of a schema. This table is intended to show how the spheres of concepts overlap each other at many points, and so leave room for a passage from each concept to whichever one we please of several other concepts. I hope, however, that no one will be led by this table to attach more importance to this little explanation, which I have merely given in passing, than ought to belong to it, from the nature of the subject. I have chosen as an illustration the concept of travelling. Its sphere partially includes four others, to any of which the sophist may pass at will; these again partly include other spheres, several of them two or more at once, and through these the sophist takes whichever way he chooses, always as if it were the only way, till at last he reaches, in good or evil, whatever end he may have in view. In passing from one sphere to another, it is only necessary always to follow the direction from the centre (the given chief concept) to the circumference, and never to reverse this process. Such a piece of sophistry may be either an unbroken speech, or it may assume the strict syllogistic form, according to what is the weak side of the hearer. Most scientific arguments, and especially philosophical demonstrations, are at bottom not much more than this, for how else would it be possible, that so much, in different ages, has not only been falsely apprehended (for error itself has a different source), but demonstrated and proved, and has yet afterwards been found to be fundamentally wrong, for example, the Leibnitz-Wolfian Philosophy, Ptolemaic Astronomy, Stahl’s Chemistry, Newton’s Theory of Colours, &c. &c.(15)

§ 10. Through all this, the question presses ever more upon us, how _certainty_ is to be attained, how _judgments __ are to be established_, what constitutes _rational knowledge_, (_wissen_), and _science_, which we rank with language and deliberate action as the third great benefit conferred by reason.

Reason is feminine in nature; it can only give after it has received. Of itself it has nothing but the empty forms of its operation. There is no absolutely pure rational knowledge except the four principles to which I have attributed metalogical truth; the principles of identity, contradiction, excluded middle, and sufficient reason of knowledge. For even the rest of logic is not absolutely pure rational knowledge. It presupposes the relations and the combinations of the spheres of concepts. But concepts in general only exist after experience of ideas of perception, and as their whole nature consists in their relation to these, it is clear that they presuppose them. No special content, however, is presupposed, but merely the existence of a content generally, and so logic as a whole may fairly pass for pure rational science. In all other sciences reason has received its content from ideas of perception; in mathematics from the relations of space and time, presented in intuition or perception prior to all experience; in pure natural science, that is, in what we know of the course of nature prior to any experience, the content of the science proceeds from the pure understanding, _i.e._, from the _a priori_ knowledge of the law of causality and its connection with those pure intuitions or perceptions of space and time. In all other sciences everything that is not derived from the sources we have just referred to belongs to experience. Speaking generally, _to know rationally_ (_wissen_) means to have in the power of the mind, and capable of being reproduced at will, such judgments as have their sufficient ground of knowledge in something outside themselves, _i.e._, are true. Thus only abstract cognition is _rational knowledge_ (_wissen_), which is therefore the result of reason, so that we cannot accurately say of the lower animals that they _rationally __ know_ (_wissen_) anything, although they have apprehension of what is presented in perception, and memory of this, and consequently imagination, which is further proved by the circumstance that they dream. We attribute consciousness to them, and therefore although the word (_bewusstsein_) is derived from the verb to know rationally (_wissen_), the conception of consciousness corresponds generally with that of idea of whatever kind it may be. Thus we attribute life to plants, but not consciousness. _Rational knowledge_ (_wissen_) is therefore abstract consciousness, the permanent possession in concepts of the reason, of what has become known in another way.

§ 11. In this regard the direct opposite of _rational knowledge_ is feeling, and therefore we must insert the explanation of feeling here. The concept which the word feeling denotes has merely a negative content, which is this, that something which is present in consciousness, _is not a concept_, _is not abstract rational knowledge_. Except this, whatever it may be, it comes under the concept of _feeling_. Thus the immeasurably wide sphere of the concept of feeling includes the most different kinds of objects, and no one can ever understand how they come together until he has recognised that they all agree in this negative respect, that they are not _abstract concepts_. For the most diverse and even antagonistic elements lie quietly side by side in this concept; for example, religious feeling, feeling of sensual pleasure, moral feeling, bodily feeling, as touch, pain, sense of colour, of sounds and their harmonies and discords, feeling of hate, of disgust, of self-satisfaction, of honour, of disgrace, of right, of wrong, sense of truth, æsthetic feeling, feeling of power, weakness, health, friendship, love, &c. &c. There is absolutely nothing in common among them except the negative quality that they are not abstract rational knowledge. But this diversity becomes more striking when the apprehension of space relations presented _a priori_ in perception, and also the knowledge of the pure understanding is brought under this concept, and when we say of all knowledge and all truth, of which we are first conscious only intuitively, and have not yet formulated in abstract concepts, we _feel_ it. I should like, for the sake of illustration, to give some examples of this taken from recent books, as they are striking proofs of my theory. I remember reading in the introduction to a German translation of Euclid, that we ought to make beginners in geometry draw the figures before proceeding to demonstrate, for in this way they would already feel geometrical truth before the demonstration brought them complete knowledge. In the same way Schleiermacher speaks in his “Critique of Ethics” of logical and mathematical feeling (p. 339), and also of the feeling of the sameness or difference of two formulas (p. 342). Again Tennemann in his “History of Philosophy” (vol. I., p. 361) says, “One _felt_ that the fallacies were not right, but could not point out the mistakes.” Now, so long as we do not regard this concept “_feeling_” from the right point of view, and do not recognise that one negative characteristic which alone is essential to it, it must constantly give occasion for misunderstanding and controversy, on account of the excessive wideness of its sphere, and its entirely negative and very limited content which is determined in a purely one-sided manner. Since then we have in German the nearly synonymous word _empfindung_ (sensation), it would be convenient to make use of it for bodily feeling, as a sub-species. This concept “feeling,” which is quite out of proportion to all others, doubtless originated in the following manner. All concepts, and concepts alone, are denoted by words; they exist only for the reason, and proceed from it. With concepts, therefore, we are already at a one-sided point of view; but from such a point of view what is near appears distinct and is set down as positive, what is farther off becomes mixed up and is soon regarded as merely negative. Thus each nation calls all others foreign: to the Greek all others are barbarians; to the Englishman all that is not England or English is continent or continental; to the believer all others are heretics, or heathens; to the noble all others are _roturiers_; to the student all others are Philistines, and so forth. Now, reason itself, strange as it may seem, is guilty of the same one-sidedness, indeed one might say of the same crude ignorance arising from vanity, for it classes under the one concept, “_feeling_,” every modification of consciousness which does not immediately belong to its own mode of apprehension, that is to say, which is _not an abstract concept_. It has had to pay the penalty of this hitherto in misunderstanding and confusion in its own province, because its own procedure had not become clear to it through thorough self-knowledge, for a special faculty of feeling has been set up, and new theories of it are constructed.

§ 12. _Rational knowledge_ (_wissen_) is then all abstract knowledge,—that is, the knowledge which is peculiar to the reason as distinguished from the understanding. Its contradictory opposite has just been explained to be the concept “feeling.” Now, as reason only reproduces, for knowledge, what has been received in another way, it does not actually extend our knowledge, but only gives it another form. It enables us to know in the abstract and generally, what first became known in sense-perception, in the concrete. But this is much more important than it appears at first sight when so expressed. For it depends entirely upon the fact that knowledge has become rational or abstract knowledge (_wissen_), that it can be safely preserved, that it is communicable and susceptible of certain and wide-reaching application to practice. Knowledge in the form of sense-perception is valid only of the particular case, extends only to what is nearest, and ends with it, for sensibility and understanding can only comprehend one object at a time. Every enduring, arranged, and planned activity must therefore proceed from principles,—that is, from abstract knowledge, and it must be conducted in accordance with them. Thus, for example, the knowledge of the relation of cause and effect arrived at by the understanding, is in itself far completer, deeper and more exhaustive than anything that can be thought about it in the abstract; the understanding alone knows in perception directly and completely the nature of the effect of a lever, of a pulley, or a cog-wheel, the stability of an arch, and so forth. But on account of the peculiarity of the knowledge of perception just referred to, that it only extends to what is immediately present, the mere understanding can never enable us to construct machines and buildings. Here reason must come in; it must substitute abstract concepts for ideas of perception, and take them as the guide of action; and if they are right, the anticipated result will happen. In the same way we have perfect knowledge in pure perception of the nature and constitution of the parabola, hyperbola, and spiral; but if we are to make trustworthy application of this knowledge to the real, it must first become abstract knowledge, and by this it certainly loses its character of intuition or perception, but on the other hand it gains the certainty and preciseness of abstract knowledge. The differential calculus does not really extend our knowledge of the curve, it contains nothing that was not already in the mere pure perception of the curve; but it alters the kind of knowledge, it changes the intuitive into an abstract knowledge, which is so valuable for application. But here we must refer to another peculiarity of our faculty of knowledge, which could not be observed until the distinction between the knowledge of the senses and understanding and abstract knowledge had been made quite clear. It is this, that relations of space cannot as such be directly translated into abstract knowledge, but only temporal quantities,—that is, numbers, are suitable for this. Numbers alone can be expressed in abstract concepts which accurately correspond to them, not spacial quantities. The concept “thousand” is just as different from the concept “ten,” as both these temporal quantities are in perception. We think of a thousand as a distinct multiple of ten, into which we can resolve it at pleasure for perception in time,—that is to say, we can count it. But between the abstract concept of a mile and that of a foot, apart from any concrete perception of either, and without the help of number, there is no accurate distinction corresponding to the quantities themselves. In both we only think of a spacial quantity in general, and if they must be completely distinguished we are compelled either to call in the assistance of intuition or perception in space, which would be a departure from abstract knowledge, or we must think the difference in _numbers_. If then we wish to have abstract knowledge of space-relations we must first translate them into time-relations,—that is, into numbers; therefore only arithmetic, and not geometry, is the universal science of quantity, and geometry must be translated into arithmetic if it is to be communicable, accurately precise and applicable in practice. It is true that a space-relation as such may also be thought in the abstract; for example, “the sine increases as the angle,” but if the quantity of this relation is to be given, it requires number for its expression. This necessity, that if we wish to have abstract knowledge of space-relations (_i.e._, rational knowledge, not mere intuition or perception), space with its three dimensions must be translated into time which has only one dimension, this necessity it is, which makes mathematics so difficult. This becomes very clear if we compare the perception of curves with their analytical calculation, or the table of logarithms of the trigonometrical functions with the perception of the changing relations of the parts of a triangle, which are expressed by them. What vast mazes of figures, what laborious calculations it would require to express in the abstract what perception here apprehends at a glance completely and with perfect accuracy, namely, how the co-sine diminishes as the sine increases, how the co-sine of one angle is the sine of another, the inverse relation of the increase and decrease of the two angles, and so forth. How time, we might say, must complain, that with its one dimension it should be compelled to express the three dimensions of space! Yet this is necessary if we wish to possess, for application, an expression, in abstract concepts, of space-relations. They could not be translated directly into abstract concepts, but only through the medium of the pure temporal quantity, number, which alone is directly related to abstract knowledge. Yet it is worthy of remark, that as space adapts itself so well to perception, and by means of its three dimensions, even its complicated relations are easily apprehended, while it eludes the grasp of abstract knowledge; time, on the contrary, passes easily into abstract knowledge, but gives very little to perception. Our perceptions of numbers in their proper element, mere time, without the help of space, scarcely extends as far as ten, and beyond that we have only abstract concepts of numbers, no knowledge of them which can be presented in perception. On the other hand, we connect with every numeral, and with all algebraical symbols, accurately defined abstract concepts.

We may further remark here that some minds only find full satisfaction in what is known through perception. What they seek is the reason and consequent of being in space, sensuously expressed; a demonstration after the manner of Euclid, or an arithmetical solution of spacial problems, does not please them. Other minds, on the contrary, seek merely the abstract concepts which are needful for applying and communicating knowledge. They have patience and memory for abstract principles, formulas, demonstrations in long trains of reasoning, and calculations, in which the symbols represent the most complicated abstractions. The latter seek preciseness, the former sensible perception. The difference is characteristic.

The greatest value of rational or abstract knowledge is that it can be communicated and permanently retained. It is principally on this account that it is so inestimably important for practice. Any one may have a direct perceptive knowledge through the understanding alone, of the causal connection, of the changes and motions of natural bodies, and he may find entire satisfaction in it; but he cannot communicate this knowledge to others until it has been made permanent for thought in concepts. Knowledge of the first kind is even sufficient for practice, if a man puts his knowledge into practice himself, in an action which can be accomplished while the perception is still vivid; but it is not sufficient if the help of others is required, or even if the action is his own but must be carried out at different times, and therefore requires a pre-conceived plan. Thus, for example, a practised billiard-player may have a perfect knowledge of the laws of the impact of elastic bodies upon each other, merely in the understanding, merely for direct perception; and for him it is quite sufficient; but on the other hand it is only the man who has studied the science of mechanics, who has, properly speaking, a rational knowledge of these laws, that is, a knowledge of them in the abstract. Such knowledge of the understanding in perception is sufficient even for the construction of machines, when the inventor of the machine executes the work himself; as we often see in the case of talented workmen, who have no scientific knowledge. But whenever a number of men, and their united action taking place at different times, is required for the completion of a mechanical work, of a machine, or a building, then he who conducts it must have thought out the plan in the abstract, and such co-operative activity is only possible through the assistance of reason. It is, however, remarkable that in the first kind of activity, in which we have supposed that one man alone, in an uninterrupted course of action, accomplishes something, abstract knowledge, the application of reason or reflection, may often be a hindrance to him; for example, in the case of billiard-playing, of fighting, of tuning an instrument, or in the case of singing. Here perceptive knowledge must directly guide action; its passage through reflection makes it uncertain, for it divides the attention and confuses the man. Thus savages and untaught men, who are little accustomed to think, perform certain physical exercises, fight with beasts, shoot with bows and arrows and the like, with a certainty and rapidity which the reflecting European never attains to, just because his deliberation makes him hesitate and delay. For he tries, for example, to hit the right position or the right point of time, by finding out the mean between two false extremes; while the savage hits it directly without thinking of the false courses open to him. In the same way it is of no use to me to know in the abstract the exact angle, in degrees and minutes, at which I must apply a razor, if I do not know it intuitively, that is, if I have not got it in my touch. The knowledge of physiognomy also, is interfered with by the application of reason. This knowledge must be gained directly through the understanding. We say that the expression, the meaning of the features, can only be _felt_, that is, it cannot be put into abstract concepts. Every man has his direct intuitive method of physiognomy and pathognomy, yet one man understands more clearly than another these _signatura rerum_. But an abstract science of physiognomy to be taught and learned is not possible; for the distinctions of difference are here so fine that concepts cannot reach them; therefore abstract knowledge is related to them as a mosaic is to a painting by a Van der Werft or a Denner. In mosaics, however fine they may be, the limits of the stones are always there, and therefore no continuous passage from one colour to another is possible, and this is also the case with regard to concepts, with their rigidity and sharp delineation; however finely we may divide them by exact definition, they are still incapable of reaching the finer modifications of the perceptible, and this is just what happens in the example we have taken, knowledge of physiognomy.(16)

This quality of concepts by which they resemble the stones of a mosaic, and on account of which perception always remains their asymptote, is also the reason why nothing good is produced in art by their means. If the singer or the virtuoso attempts to guide his execution by reflection he remains silent. And this is equally true of the composer, the painter, and the poet. The concept always remains unfruitful in art; it can only direct the technical part of it, its sphere is science. We shall consider more fully in the third book, why all true art proceeds from sensuous knowledge, never from the concept. Indeed, with regard to behaviour also, and personal agreeableness in society, the concept has only a negative value in restraining the grosser manifestations of egotism and brutality; so that a polished manner is its commendable production. But all that is attractive, gracious, charming in behaviour, all affectionateness and friendliness, must not proceed from the concepts, for if it does, “we feel intention, and are put out of tune.” All dissimulation is the work of reflection; but it cannot be maintained constantly and without interruption: “_nemo __ potest personam diu ferre fictum_,” says Seneca in his book _de clementia_; and so it is generally found out and loses its effect. Reason is needed in the full stress of life, where quick conclusions, bold action, rapid and sure comprehension are required, but it may easily spoil all if it gains the upper hand, and by perplexing hinders the intuitive, direct discovery, and grasp of the right by simple understanding, and thus induces irresolution.

Lastly, virtue and holiness do not proceed from reflection, but from the inner depths of the will, and its relation to knowledge. The exposition of this belongs to another part of our work; this, however, I may remark here, that the dogmas relating to ethics may be the same in the reason of whole nations, but the action of every individual different; and the converse also holds good; action, we say, is guided by _feelings_,—that is, simply not by concepts, but as a matter of fact by the ethical character. Dogmas occupy the idle reason; but action in the end pursues its own course independently of them, generally not according to abstract rules, but according to unspoken maxims, the expression of which is the whole man himself. Therefore, however different the religious dogmas of nations may be, yet in the case of all of them, a good action is accompanied by unspeakable satisfaction, and a bad action by endless remorse. No mockery can shake the former; no priest’s absolution can deliver from the latter. Notwithstanding this, we must allow, that for the pursuit of a virtuous life, the application of reason is needful; only it is not its source, but has the subordinate function of preserving resolutions which have been made, of providing maxims to withstand the weakness of the moment, and give consistency to action. It plays the same part ultimately in art also, where it has just as little to do with the essential matter, but assists in carrying it out, for genius is not always at call, and yet the work must be completed in all its parts and rounded off to a whole.(17)

§ 13. All these discussions of the advantages and disadvantages of the application of reason are intended to show, that although abstract rational knowledge is the reflex of ideas of perception, and is founded on them, it is by no means in such entire congruity with them that it could everywhere take their place: indeed it never corresponds to them quite accurately. And thus, as we have seen, many human actions can only be performed by the help of reason and deliberation, and yet there are some which are better performed without its assistance. This very incongruity of sensuous and abstract knowledge, on account of which the latter always merely approximates to the former, as mosaic approximates to painting, is the cause of a very remarkable phenomenon which, like reason itself, is peculiar to human nature, and of which the explanations that have ever anew been attempted, are insufficient: I mean _laughter_. On account of the source of this phenomenon, we cannot avoid giving the explanation of it here, though it again interrupts the course of our work to do so. The cause of laughter in every case is simply the sudden perception of the incongruity between a concept and the real objects which have been thought through it in some relation, and laughter itself is just the expression of this incongruity. It often occurs in this way: two or more real objects are thought through _one_ concept, and the identity of the concept is transferred to the objects; it then becomes strikingly apparent from the entire difference of the objects in other respects, that the concept was only applicable to them from a one-sided point of view. It occurs just as often, however, that the incongruity between a single real object and the concept under which, from one point of view, it has rightly been subsumed, is suddenly felt. Now the more correct the subsumption of such objects under a concept may be from one point of view, and the greater and more glaring their incongruity with it, from another point of view, the greater is the ludicrous effect which is produced by this contrast. All laughter then is occasioned by a paradox, and therefore by unexpected subsumption, whether this is expressed in words or in actions. This, briefly stated, is the true explanation of the ludicrous.

I shall not pause here to relate anecdotes as examples to illustrate my theory; for it is so simple and comprehensible that it does not require them, and everything ludicrous which the reader may remember is equally valuable as a proof of it. But the theory is confirmed and illustrated by distinguishing two species into which the ludicrous is divided, and which result from the theory. Either, we have previously known two or more very different real objects, ideas of sense-perception, and have intentionally identified them through the unity of a concept which comprehends them both; this species of the ludicrous is called _wit_. Or, conversely, the concept is first present in knowledge, and we pass from it to reality, and to operation upon it, to action: objects which in other respects are fundamentally different, but which are all thought in that one concept, are now regarded and treated in the same way, till, to the surprise and astonishment of the person acting, the great difference of their other aspects appears: this species of the ludicrous is called _folly_. Therefore everything ludicrous is either a flash of wit or a foolish

## action, according as the procedure has been from the discrepancy of the

objects to the identity of the concept, or the converse; the former always intentional, the latter always unintentional, and from without. To seem to reverse the starting-point, and to conceal wit with the mask of folly, is the art of the jester and the clown. Being quite aware of the diversity of the objects, the jester unites them, with secret wit, under one concept, and then starting from this concept he receives from the subsequently discovered diversity of the objects the surprise which he himself prepared. It follows from this short but sufficient theory of the ludicrous, that, if we set aside the last case, that of the jester, wit must always show itself in words, folly generally in actions, though also in words, when it only expresses an intention and does not actually carry it out, or when it shows itself merely in judgments and opinions.

_Pedantry_ is a form of folly. It arises in this way: a man lacks confidence in his own understanding, and, therefore, does not wish to trust to it, to recognise what is right directly in the particular case. He, therefore, puts it entirely under the control of the reason, and seeks to be guided by reason in everything; that is to say, he tries always to proceed from general concepts, rules, and maxims, and to confine himself strictly to them in life, in art, and even in moral conduct. Hence that clinging to the form, to the manner, to the expression and word which is characteristic of pedantry, and which with it takes the place of the real nature of the matter. The incongruity then between the concept and reality soon shows itself here, and it becomes evident that the former never condescends to the particular case, and that with its generality and rigid definiteness it can never accurately apply to the fine distinctions of difference and innumerable modifications of the actual. Therefore, the pedant, with his general maxims, almost always misses the mark in life, shows himself to be foolish, awkward, useless. In art, in which the concept is unfruitful, he produces lifeless, stiff, abortive mannerisms. Even with regard to ethics, the purpose to act rightly or nobly cannot always be carried out in accordance with abstract maxims; for in many cases the excessively nice distinctions in the nature of the circumstances necessitate a choice of the right proceeding directly from the character; for the application of mere abstract maxims sometimes gives false results, because the maxims only half apply; and sometimes cannot be carried out, because they are foreign to the individual character of the actor, and this never allows itself to be entirely discovered; therefore, inconsistencies arise. Since then Kant makes it a condition of the moral worth of an action, that it shall proceed from pure rational abstract maxims, without any inclination or momentary emotion, we cannot entirely absolve him from the reproach of encouraging moral pedantry. This reproach is the significance of Schiller’s epigram, entitled “Scruples of Conscience.” When we speak, especially in connection with politics, of doctrinaires, theorists, savants, and so forth, we mean pedants, that is, persons who know the things well in the abstract, but not in the concrete. Abstraction consists in thinking away the less general predicates; but it is precisely upon these that so much depends in practice.

To complete our theory it remains for us to mention a spurious kind of wit, the play upon words, the _calembourg_, the pun, to which may be added the equivocation, the _double entendre_, the chief use of which is the expression of what is obscene. Just as the witticism brings two very different real objects under one concept, the pun brings two different concepts, by the assistance of accident, under one word. The same contrast appears, only familiar and more superficial, because it does not spring from the nature of things, but merely from the accident of nomenclature. In the case of the witticism the identity is in the concept, the difference in the reality, but in the case of the pun the difference is in the concepts and the identity in the reality, for the terminology is here the reality. It would only be a somewhat far-fetched comparison if we were to say that the pun is related to the witticism as the parabola (_sic_) of the upper inverted cone to that of the lower. The misunderstanding of the word or the _quid pro quo_ is the unintentional pun, and is related to it exactly as folly is to wit. Thus the deaf man often affords occasion for laughter, just as much as the fool, and inferior writers of comedy often use the former for the latter to raise a laugh.

I have treated laughter here only from the psychical side; with regard to the physical side, I refer to what is said on the subject in the “Parerga,” vol. II. ch. vi., § 98.(18)

§ 14. By means of these various discussions it is hoped that both the difference and the relation between the process of knowledge that belongs to the reason, rational knowledge, the concept on the one hand, and the direct knowledge in purely sensuous, mathematical intuition or perception, and apprehension by the understanding on the other hand, has been clearly brought out. This remarkable relation of our kinds of knowledge led us almost inevitably to give, in passing, explanations of feeling and of laughter, but from all this we now turn back to the further consideration of science as the third great benefit which reason confers on man, the other two being speech and deliberate action. The general discussion of science which now devolves upon us, will be concerned partly with its form, partly with the foundation of its judgments, and lastly with its content.

We have seen that, with the exception of the basis of pure logic, rational knowledge in general has not its source in the reason itself; but having been otherwise obtained as knowledge of perception, it is stored up in the reason, for through reason it has entirely changed its character, and has become abstract knowledge. All rational knowledge, that is, knowledge that has been raised to consciousness in the abstract, is related to science strictly so called, as a fragment to the whole. Every one has gained a rational knowledge of many different things through experience, through consideration of the individual objects presented to him, but only he who sets himself the task of acquiring a complete knowledge in the abstract of a particular class of objects, strives after science. This class can only be marked off by means of a concept; therefore, at the beginning of every science there stands a concept, and by means of it the class of objects concerning which this science promises a complete knowledge in the abstract, is separated in thought from the whole world of things. For example, the concept of space-relations, or of the action of unorganised bodies upon each other, or of the nature of plants, or of animals, or of the successive changes of the surface of the globe, or of the changes of the human race as a whole, or of the construction of a language, and so forth. If science sought to obtain the knowledge of its object, by investigating each individual thing that is thought through the concept, till by degrees it had learned the whole, no human memory would be equal to the task, and no certainty of completeness would be obtainable. Therefore, it makes use of that property of concept-spheres explained above, that they include each other, and it concerns itself mainly with the wider spheres which lie within the concept of its object in general. When the relations of these spheres to each other have been determined, all that is thought in them is also generally determined, and can now be more and more accurately determined by the separation of smaller and smaller concept-spheres. In this way it is possible for a science to comprehend its object completely. This path which it follows to knowledge, the path from the general to the particular, distinguishes it from ordinary rational knowledge; therefore, systematic form is an essential and characteristic feature of science. The combination of the most general concept-spheres of every science, that is, the knowledge of its first principles, is the indispensable condition of mastering it; how far we advance from these to the more special propositions is a matter of choice, and does not increase the thoroughness but only the extent of our knowledge of the science. The number of the first principles to which all the rest are subordinated, varies greatly in the different sciences, so that in some there is more subordination, in others more co-ordination; and in this respect, the former make greater claims upon the judgment, the latter upon the memory. It was known to the schoolmen,(19) that, as the syllogism requires two premises, no science can proceed from a single first principle which cannot be the subject of further deduction, but must have several, at least two. The specially classifying sciences: Zoology, Botany, and also Physics and Chemistry, inasmuch as they refer all inorganic action to a few fundamental forces, have most subordination; history, on the other hand, has really none at all; for the general in it consists merely in the survey of the principal periods, from which, however, the particular events cannot be deduced, and are only subordinated to them according to time, but according to the concept are co-ordinate with them. Therefore, history, strictly speaking, is certainly rational knowledge, but is not science. In mathematics, according to Euclid’s treatment, the axioms alone are indemonstrable first principles, and all demonstrations are in gradation strictly subordinated to them. But this method of treatment is not essential to mathematics, and in fact each proposition introduces quite a new space construction, which in itself is independent of those which precede it, and indeed can be completely comprehended from itself, quite independently of them, in the pure intuition or perception of space, in which the most complicated construction is just as directly evident as the axiom; but of this more fully hereafter. Meanwhile every mathematical proposition remains always a universal truth, which is valid for innumerable particular cases; and a graduated process from the simple to the complicated propositions which are to be deduced from them, is also essential to mathematics; therefore, in every respect mathematics is a science. The completeness of a science as such, that is, in respect of form, consists in there being as much subordination and as little co-ordination of the principles as possible. Scientific talent in general is, therefore, the faculty of subordinating the concept-spheres according to their different determinations, so that, as Plato repeatedly counsels, a science shall not be constituted by a general concept and an indefinite multiplicity immediately under it, but that knowledge shall descend by degrees from the general to the

## particular, through intermediate concepts and divisions, according to

closer and closer definitions. In Kantian language this is called satisfying equally the law of homogeneity and that of specification. It arises from this peculiar nature of scientific completeness, that the aim of science is not greater certainty—for certainty may be possessed in just as high a degree by the most disconnected particular knowledge—but its aim is rather the facilitating of rational knowledge by means of its form, and the possibility of the completeness of rational knowledge which this form affords. It is therefore a very prevalent but perverted opinion that the scientific character of knowledge consists in its greater certainty, and just as false is the conclusion following from this, that, strictly speaking, the only sciences are mathematics and logic, because only in them, on account of their purely _a priori_ character, is there unassailable certainty of knowledge. This advantage cannot be denied them, but it gives them no special claim to be regarded as sciences; for the special characteristic of science does not lie in certainty but in the systematic form of knowledge, based on the gradual descent from the general to the particular. The process of knowledge from the general to the particular, which is peculiar to the sciences, involves the necessity that in the sciences much should be established by deduction from preceding propositions, that is to say, by demonstration; and this has given rise to the old mistake that only what has been demonstrated is absolutely true, and that every truth requires a demonstration; whereas, on the contrary, every demonstration requires an undemonstrated truth, which ultimately supports it, or it may be, its own demonstration. Therefore a directly established truth is as much to be preferred to a truth established by demonstration as water from the spring is to water from the aqueduct. Perception, partly pure _a priori_, as it forms the basis of mathematics, partly empirical _a posteriori_, as it forms the basis of all the other sciences, is the source of all truth and the foundation of all science. (Logic alone is to be excepted, which is not founded upon perception but yet upon _direct_ knowledge by the reason of its own laws.) Not the demonstrated judgments nor their demonstrations, but judgments which are created directly out of perception, and founded upon it rather than on any demonstrations, are to science what the sun is to the world; for all light proceeds from them, and lighted by their light the others give light also. To establish the truth of such primary judgments directly from perception, to raise such strongholds of science from the innumerable multitude of real objects, that is the work of the _faculty of judgment_, which consists in the power of rightly and accurately carrying over into abstract consciousness what is known in perception, and judgment is consequently the mediator between understanding and reason. Only extraordinary and exceptional strength of judgment in the individual can actually advance science; but every one who is possessed of a healthy reason is able to deduce propositions from propositions, to demonstrate, to draw conclusions. To lay down and make permanent for reflection, in suitable concepts, what is known through perception, so that, on the one hand, what is common to many real objects is thought through _one_ concept, and, on the other hand, their points of difference are each thought through one concept, so that the different shall be known and thought as different in spite of a partial agreement, and the identical shall be known and thought as identical in spite of a

## partial difference, all in accordance with the end and intention which in

each case is in view; all this is done by the _faculty of judgment_. Deficiency in judgment is _silliness_. The silly man fails to grasp, now the partial or relative difference of concepts which in one aspect are identical, now the identity of concepts which are relatively or partially different. To this explanation of the faculty of judgment, moreover, Kant’s division of it into reflecting and subsuming judgment may be applied, according as it passes from the perceived objects to the concepts, or from the latter to the former; in both cases always mediating between empirical knowledge of the understanding and the reflective knowledge of the reason. There can be no truth which could be brought out by means of syllogisms alone; and the necessity of establishing truth by means of syllogisms is merely relative, indeed subjective. Since all demonstration is syllogistic, in the case of a new truth we must first seek, not for a demonstration, but for direct evidence, and only in the absence of such evidence is a demonstration to be temporarily made use of. No science is susceptible of demonstration throughout any more than a building can stand in the air; all its demonstrations must ultimately rest upon what is perceived, and consequently cannot be demonstrated, for the whole world of reflection rests upon and is rooted in the world of perception. All primal, that is, original, _evidence_ is a _perception_, as the word itself indicates. Therefore it is either empirical or founded upon the perception _a priori_ of the conditions of possible experience. In both cases it affords only immanent, not transcendent knowledge. Every concept has its worth and its existence only in its relation, sometimes very indirect, to an idea of perception; what is true of the concepts is also true of the judgments constructed out of them, and of all science. Therefore it must in some way be possible to know directly without demonstrations or syllogisms every truth that is arrived at through syllogisms and communicated by demonstrations. This is most difficult in the case of certain complicated mathematical propositions at which we only arrive by chains of syllogisms; for example, the calculation of the chords and tangents to all arcs by deduction from the proposition of Pythagoras. But even such a truth as this cannot essentially and solely rest upon abstract principles, and the space-relations which lie at its foundation also must be capable of being so presented _a priori_ in pure intuition or perception that the truth of their abstract expression is directly established. But of mathematical demonstration we shall speak more fully shortly.

It is true we often hear men speak in a lofty strain of sciences which rest entirely upon correct conclusions drawn from sure premises, and which are consequently unassailable. But through pure logical reasoning, however true the premises may be, we shall never receive more than an articulate expression and exposition of what lies already complete in the premises; thus we shall only _explicitly_ expound what was already _implicitly_ understood. The esteemed sciences referred to are, however, specially the mathematical sciences, particularly astronomy. But the certainty of astronomy arises from the fact that it has for its basis the intuition or perception of space, which is given _a priori_, and is therefore infallible. All space-relations, however, follow from each other with a necessity (ground of being) which affords _a priori_ certainty, and they can therefore be safely deduced from each other. To these mathematical properties we have only to add one force of nature, gravity, which acts precisely in relation to the masses and the square of the distance; and, lastly, the law of inertia, which follows from the law of causality and is therefore true _a priori_, and with it the empirical datum of the motion impressed, once for all, upon each of these masses. This is the whole material of astronomy, which both by its simplicity and its certainty leads to definite results, which are highly interesting on account of the vastness and importance of the objects. For example, if I know the mass of a planet and the distance of its satellite from it, I can tell with certainty the period of the revolution of the latter according to Kepler’s second law. But the ground of this law is, that with this distance only this velocity will both chain the satellite to the planet and prevent it from falling into it. Thus it is only upon such a geometrical basis, that is, by means of an intuition or perception _a priori_, and also under the application of a law of nature, that much can be arrived at by means of syllogisms, for here they are merely like bridges from _one_ sensuous apprehension to others; but it is not so with mere pure syllogistic reasoning in the exclusively logical method. The source of the first fundamental truths of astronomy is, however, properly induction, that is, the comprehension of what is given in many perceptions in one true and directly founded judgment. From this, hypotheses are afterwards constructed, and their confirmation by experience, as induction approaching to completeness, affords the proof of the first judgment. For example, the apparent motion of the planets is known empirically; after many false hypotheses with regard to the spacial connection of this motion (planetary course) the right one was at last found, then the laws which it obeyed (the laws of Kepler), and, lastly, the cause of these laws (universal gravitation), and the empirically known agreement of all observed cases with the whole of the hypotheses, and with their consequences, that is to say, induction, established them with complete certainty. The invention of the hypotheses was the work of the judgment, which rightly comprehended the given facts and expressed them accordingly; but induction, that is, a multitude of perceptions, confirmed their truth. But their truth could also be known directly, and by a single empirical perception, if we could pass freely through space and had telescopic eyes. Therefore, here also syllogisms are not the essential and only source of knowledge, but really only a makeshift.

As a third example taken from a different sphere we may mention that the so-called metaphysical truths, that is, such truths as those to which Kant assigns the position of the metaphysical first principles of natural science, do not owe their evidence to demonstration. What is _a priori_ certain we know directly; as the form of all knowledge, it is known to us with the most complete necessity. For example, that matter is permanent, that is, can neither come into being nor pass away, we know directly as negative truth; for our pure intuition or perception of space and time gives the possibility of motion; in the law of causality the understanding affords us the possibility of change of form and quality, but we lack powers of the imagination for conceiving the coming into being or passing away of matter. Therefore that truth has at all times been evident to all men everywhere, nor has it ever been seriously doubted; and this could not be the case if it had no other ground of knowledge than the abstruse and exceedingly subtle proof of Kant. But besides this, I have found Kant’s proof to be false (as is explained in the Appendix), and have shown above that the permanence of matter is to be deduced, not from the share which time has in the possibility of experience, but from the share which belongs to space. The true foundation of all truths which in this sense are called metaphysical, that is, abstract expressions of the necessary and universal forms of knowledge, cannot itself lie in abstract principles; but only in the immediate consciousness of the forms of the idea communicating itself in apodictic assertions _a priori_, and fearing no refutation. But if we yet desire to give a proof of them, it can only consist in showing that what is to be proved is contained in some truth about which there is no doubt, either as a part of it or as a presupposition. Thus, for example, I have shown that all empirical perception implies the application of the law of causality, the knowledge of which is hence a condition of all experience, and therefore cannot be first given and conditioned through experience as Hume thought. Demonstrations in general are not so much for those who wish to learn as for those who wish to dispute. Such persons stubbornly deny directly established insight; now only the truth can be consistent in all directions, and therefore we must show such persons that they admit under _one_ form and indirectly, what they deny under another form and directly; that is, the logically necessary connection between what is denied and what is admitted.

It is also a consequence of the scientific form, the subordination of everything particular under a general, and so on always to what is more general, that the truth of many propositions is only logically proved,—that is, through their dependence upon other propositions, through syllogisms, which at the same time appear as proofs. But we must never forget that this whole form of science is merely a means of rendering knowledge more easy, not a means to greater certainty. It is easier to discover the nature of an animal, by means of the species to which it belongs, and so on through the genus, family, order, and class, than to examine on every occasion the animal presented to us: but the truth of all propositions arrived at syllogistically is always conditioned by and ultimately dependent upon some truth which rests not upon reasoning but upon perception. If this perception were always as much within our reach as a deduction through syllogisms, then it would be in every respect preferable. For every deduction from concepts is exposed to great danger of error, on account of the fact we have considered above, that so many spheres lie partly within each other, and that their content is often vague or uncertain. This is illustrated by a multitude of demonstrations of false doctrines and sophisms of every kind. Syllogisms are indeed perfectly certain as regards form, but they are very uncertain on account of their matter, the concepts. For, on the one hand, the spheres of these are not sufficiently sharply defined, and, on the other hand, they intersect each other in so many ways that one sphere is in part contained in many others, and we may pass at will from it to one or another of these, and from this sphere again to others, as we have already shown. Or, in other words, the minor term and also the middle can always be subordinated to different concepts, from which we may choose at will the major and the middle, and the nature of the conclusion depends on this choice. Consequently immediate evidence is always much to be preferred to reasoned truth, and the latter is only to be accepted when the former is too remote, and not when it is as near or indeed nearer than the latter. Accordingly we saw above that, as a matter of fact, in the case of logic, in which the immediate knowledge in each individual case lies nearer to hand than deduced scientific knowledge, we always conduct our thought according to our immediate knowledge of the laws of thought, and leave logic unused.(20)

§ 15. If now with our conviction that perception is the primary source of all evidence, and that only direct or indirect connection with it is absolute truth; and further, that the shortest way to this is always the surest, as every interposition of concepts means exposure to many deceptions; if, I say, we now turn with this conviction to mathematics, as it was established as a science by Euclid, and has remained as a whole to our own day, we cannot help regarding the method it adopts, as strange and indeed perverted. We ask that every logical proof shall be traced back to an origin in perception; but mathematics, on the contrary, is at great pains deliberately to throw away the evidence of perception which is peculiar to it, and always at hand, that it may substitute for it a logical demonstration. This must seem to us like the action of a man who cuts off his legs in order to go on crutches, or like that of the prince in the “_Triumph der Empfindsamkeit_” who flees from the beautiful reality of nature, to delight in a stage scene that imitates it. I must here refer to what I have said in the sixth chapter of the essay on the principle of sufficient reason, and take for granted that it is fresh and present in the memory of the reader; so that I may link my observations on to it without explaining again the difference between the mere ground of knowledge of a mathematical truth, which can be given logically, and the ground of being, which is the immediate connection of the parts of space and time, known only in perception. It is only insight into the ground of being that secures satisfaction and thorough knowledge. The mere ground of knowledge must always remain superficial; it can afford us indeed rational knowledge _that_ a thing is as it is, but it cannot tell _why_ it is so. Euclid chose the latter way to the obvious detriment of the science. For just at the beginning, for example, when he ought to show once for all how in a triangle the angles and sides reciprocally determine each other, and stand to each other in the relation of reason and consequent, in accordance with the form which the principle of sufficient reason has in pure space, and which there, as in every other sphere, always affords the necessity that a thing is as it is, because something quite different from it, is as it is; instead of in this way giving a thorough insight into the nature of the triangle, he sets up certain disconnected arbitrarily chosen propositions concerning the triangle, and gives a logical ground of knowledge of them, through a laborious logical demonstration, based upon the principle of contradiction. Instead of an exhaustive knowledge of these space-relations we therefore receive merely certain results of them, imparted to us at pleasure, and in fact we are very much in the position of a man to whom the different effects of an ingenious machine are shown, but from whom its inner connection and construction are withheld. We are compelled by the principle of contradiction to admit that what Euclid demonstrates is true, but we do not comprehend _why_ it is so. We have therefore almost the same uncomfortable feeling that we experience after a juggling trick, and, in fact, most of Euclid’s demonstrations are remarkably like such feats. The truth almost always enters by the back door, for it manifests itself _per accidens_ through some contingent circumstance. Often a _reductio ad absurdum_ shuts all the doors one after another, until only one is left through which we are therefore compelled to enter. Often, as in the proposition of Pythagoras, lines are drawn, we don’t know why, and it afterwards appears that they were traps which close unexpectedly and take prisoner the assent of the astonished learner, who must now admit what remains wholly inconceivable in its inner connection, so much so, that he may study the whole of Euclid through and through without gaining a real insight into the laws of space-relations, but instead of them he only learns by heart certain results which follow from them. This specially empirical and unscientific knowledge is like that of the doctor who knows both the disease and the cure for it, but does not know the connection between them. But all this is the necessary consequence if we capriciously reject the special kind of proof and evidence of one species of knowledge, and forcibly introduce in its stead a kind which is quite foreign to its nature. However, in other respects the manner in which this has been accomplished by Euclid deserves all the praise which has been bestowed on him through so many centuries, and which has been carried so far that his method of treating mathematics has been set up as the pattern of all scientific exposition. Men tried indeed to model all the sciences after it, but later they gave up the attempt without quite knowing why. Yet in our eyes this method of Euclid in mathematics can appear only as a very brilliant piece of perversity. But when a great error in life or in science has been intentionally and methodically carried out with universal applause, it is always possible to discover its source in the philosophy which prevailed at the time. The Eleatics first brought out the difference, and indeed often the conflict, that exists between what is perceived, φαινομενον,(21) and what is thought, νουμενον, and used it in many ways in their philosophical epigrams, and also in sophisms. They were followed later by the Megarics, the Dialecticians, the Sophists, the New-Academy, and the Sceptics; these drew attention to the illusion, that is to say, to the deception of the senses, or rather of the understanding which transforms the data of the senses into perception, and which often causes us to see things to which the reason unhesitatingly denies reality; for example, a stick broken in water, and such like. It came to be known that sense-perception was not to be trusted unconditionally, and it was therefore hastily concluded that only rational, logical thought could establish truth; although Plato (in the Parmenides), the Megarics, Pyrrho, and the New-Academy, showed by examples (in the manner which was afterwards adopted by Sextus Empiricus) how syllogisms and concepts were also sometimes misleading, and indeed produced paralogisms and sophisms which arise much more easily and are far harder to explain than the illusion of sense-perception. However, this rationalism, which arose in opposition to empiricism, kept the upper hand, and Euclid constructed the science of mathematics in accordance with it. He was compelled by necessity to found the axioms upon evidence of perception (φαινομενον), but all the rest he based upon reasoning (νουμενον). His method reigned supreme through all the succeeding centuries, and it could not but do so as long as pure intuition or perception, _a priori_, was not distinguished from empirical perception. Certain passages from the works of Proclus, the commentator of Euclid, which Kepler translated into Latin in his book, “De Harmonia Mundi,” seem to show that he fully recognised this distinction. But Proclus did not attach enough importance to the matter; he merely mentioned it by the way, so that he remained unnoticed and accomplished nothing. Therefore, not till two thousand years later will the doctrine of Kant, which is destined to make such great changes in all the knowledge, thought, and action of European nations, produce this change in mathematics also. For it is only after we have learned from this great man that the intuitions or perceptions of space and time are quite different from empirical perceptions, entirely independent of any impression of the senses, conditioning it, not conditioned by it, _i.e._, are _a priori_, and therefore are not exposed to the illusions of sense; only after we have learned this, I say, can we comprehend that Euclid’s logical method of treating mathematics is a useless precaution, a crutch for sound legs, that it is like a wanderer who during the night mistakes a bright, firm road for water, and carefully avoiding it, toils over the broken ground beside it, content to keep from point to point along the edge of the supposed water. Only now can we affirm with certainty that what presents itself to us as necessary in the perception of a figure, does not come from the figure on the paper, which is perhaps very defectively drawn, nor from the abstract concept under which we think it, but immediately from the form of all knowledge of which we are conscious _a priori_. This is always the principle of sufficient reason; here as the form of perception, _i.e._, space, it is the principle of the ground of being, the evidence and validity of which is, however, just as great and as immediate as that of the principle of the ground of knowing, _i.e._, logical certainty. Thus we need not and ought not to leave the peculiar province of mathematics in order to put our trust only in logical proof, and seek to authenticate mathematics in a sphere which is quite foreign to it, that of concepts. If we confine ourselves to the ground peculiar to mathematics, we gain the great advantage that in it the rational knowledge _that_ something is, is one with the knowledge _why_ it is so, whereas the method of Euclid entirely separates these two, and lets us know only the first, not the second. Aristotle says admirably in the Analyt., post. i. 27: “Ακριβεστερα δ᾽ επιστημη επιστημης και προτερα, ἡτε του ὁτι και του διοτι ἡ αυτη, αλλα μη χωρις του ὁτι, της του διοτι” (_Subtilior autem et praestantior ea est scientia, quâ_ QUOD _aliquid sit, et_ CUR _sit una simulque intelligimus non separatim_ QUOD, _et_ CUR _sit_). In physics we are only satisfied when the knowledge that a thing is as it is is combined with the knowledge why it is so. To know that the mercury in the Torricellian tube stands thirty inches high is not really rational knowledge if we do not know that it is sustained at this height by the counterbalancing weight of the atmosphere. Shall we then be satisfied in mathematics with the _qualitas occulta_ of the circle that the segments of any two intersecting chords always contain equal rectangles? That it is so Euclid certainly demonstrates in the 35th Prop. of the Third Book; _why_ it is so remains doubtful. In the same way the proposition of Pythagoras teaches us a _qualitas occulta_ of the right-angled triangle; the stilted and indeed fallacious demonstration of Euclid forsakes us at the _why_, and a simple figure, which we already know, and which is present to us, gives at a glance far more insight into the matter, and firm inner conviction of that necessity, and of the dependence of that quality upon the right angle:—

[Illustration]

In the case of unequal catheti also, and indeed generally in the case of every possible geometrical truth, it is quite possible to obtain such a conviction based on perception, because these truths were always discovered by such an empirically known necessity, and their demonstration was only thought out afterwards in addition. Thus we only require an analysis of the process of thought in the first discovery of a geometrical truth in order to know its necessity empirically. It is the analytical method in general that I wish for the exposition of mathematics, instead of the synthetical method which Euclid made use of. Yet this would have very great, though not insuperable, difficulties in the case of complicated mathematical truths. Here and there in Germany men are beginning to alter the exposition of mathematics, and to proceed more in this analytical way. The greatest effort in this direction has been made by Herr Kosack, teacher of mathematics and physics in the Gymnasium at Nordhausen, who added a thorough attempt to teach geometry according to my principles to the programme of the school examination on the 6th of April 1852.

In order to improve the method of mathematics, it is especially necessary to overcome the prejudice that demonstrated truth has any superiority over what is known through perception, or that logical truth founded upon the principle of contradiction has any superiority over metaphysical truth, which is immediately evident, and to which belongs the pure intuition or perception of space.

That which is most certain, and yet always inexplicable, is what is involved in the principle of sufficient reason, for this principle, in its different aspects, expresses the universal form of all our ideas and knowledge. All explanation consists of reduction to it, exemplification in the particular case of the connection of ideas expressed generally through it. It is thus the principle of all explanation, and therefore it is neither susceptible of an explanation itself, nor does it stand in need of it; for every explanation presupposes it, and only obtains meaning through it. Now, none of its forms are superior to the rest; it is equally certain and incapable of demonstration as the principle of the ground of being, or of change, or of action, or of knowing. The relation of reason and consequent is a necessity in all its forms, and indeed it is, in general, the source of the concept of necessity, for necessity has no other meaning. If the reason is given there is no other necessity than that of the consequent, and there is no reason that does not involve the necessity of the consequent. Just as surely then as the consequent expressed in the conclusion follows from the ground of knowledge given in the premises, does the ground of being in space determine its consequent in space: if I know through perception the relation of these two, this certainty is just as great as any logical certainty. But every geometrical proposition is just as good an expression of such a relation as one of the twelve axioms; it is a metaphysical truth, and as such, just as certain as the principle of contradiction itself, which is a metalogical truth, and the common foundation of all logical demonstration. Whoever denies the necessity, exhibited for intuition or perception, of the space-relations expressed in any proposition, may just as well deny the axioms, or that the conclusion follows from the premises, or, indeed, he may as well deny the principle of contradiction itself, for all these relations are equally undemonstrable, immediately evident and known _a priori_. For any one to wish to derive the necessity of space-relations, known in intuition or perception, from the principle of contradiction by means of a logical demonstration is just the same as for the feudal superior of an estate to wish to hold it as the vassal of another. Yet this is what Euclid has done. His axioms only, he is compelled to leave resting upon immediate evidence; all the geometrical truths which follow are demonstrated logically, that is to say, from the agreement of the assumptions made in the proposition with the axioms which are presupposed, or with some earlier proposition; or from the contradiction between the opposite of the proposition and the assumptions made in it, or the axioms, or earlier propositions, or even itself. But the axioms themselves have no more immediate evidence than any other geometrical problem, but only more simplicity on account of their smaller content.

When a criminal is examined, a _procès-verbal_ is made of his statement in order that we may judge of its truth from its consistency. But this is only a makeshift, and we are not satisfied with it if it is possible to investigate the truth of each of his answers for itself; especially as he might lie consistently from the beginning. But Euclid investigated space according to this first method. He set about it, indeed, under the correct assumption that nature must everywhere be consistent, and that therefore it must also be so in space, its fundamental form. Since then the parts of space stand to each other in a relation of reason and consequent, no single property of space can be different from what it is without being in contradiction with all the others. But this is a very troublesome, unsatisfactory, and roundabout way to follow. It prefers indirect knowledge to direct, which is just as certain, and it separates the knowledge that a thing is from the knowledge why it is, to the great disadvantage of the science; and lastly, it entirely withholds from the beginner insight into the laws of space, and indeed renders him unaccustomed to the special investigation of the ground and inner connection of things, inclining him to be satisfied with a mere historical knowledge that a thing is as it is. The exercise of acuteness which this method is unceasingly extolled as affording consists merely in this, that the pupil practises drawing conclusions, _i.e._, he practises applying the principle of contradiction, but specially he exerts his memory to retain all those data whose agreement is to be tested. Moreover, it is worth noticing that this method of proof was applied only to geometry and not to arithmetic. In arithmetic the truth is really allowed to come home to us through perception alone, which in it consists simply in counting. As the perception of numbers is in _time alone_, and therefore cannot be represented by a sensuous schema like the geometrical figure, the suspicion that perception is merely empirical, and possibly illusive, disappeared in arithmetic, and the introduction of the logical method of proof into geometry was entirely due to this suspicion. As time has only one dimension, counting is the only arithmetical operation, to which all others may be reduced; and yet counting is just intuition or perception _a priori_, to which there is no hesitation in appealing here, and through which alone everything else, every sum and every equation, is ultimately proved. We prove, for example, not that (7 + 9 × 8 - 2)/3 = 42; but we refer to the pure perception in time, counting thus makes each individual problem an axiom. Instead of the demonstrations that fill geometry, the whole content of arithmetic and algebra is thus simply a method of abbreviating counting. We mentioned above that our immediate perception of numbers in time extends only to about ten. Beyond this an abstract concept of the numbers, fixed by a word, must take the place of the perception; which does not therefore actually occur any longer, but is only indicated in a thoroughly definite manner. Yet even so, by the important assistance of the system of figures which enables us to represent all larger numbers by the same small ones, intuitive or perceptive evidence of every sum is made possible, even where we make such use of abstraction that not only the numbers, but indefinite quantities and whole operations are thought only in the abstract and indicated as so thought, as [sqrt](r^b) so that we do not perform them, but merely symbolise them.

We might establish truth in geometry also, through pure _a priori_ perception, with the same right and certainty as in arithmetic. It is in fact always this necessity, known through perception in accordance with the principle of sufficient reason of being, which gives to geometry its principal evidence, and upon which in the consciousness of every one, the certainty of its propositions rests. The stilted logical demonstration is always foreign to the matter, and is generally soon forgotten, without weakening our conviction. It might indeed be dispensed with altogether without diminishing the evidence of geometry, for this is always quite independent of such demonstration, which never proves anything we are not convinced of already, through another kind of knowledge. So far then it is like a cowardly soldier, who adds a wound to an enemy slain by another, and then boasts that he slew him himself.(22)

After all this we hope there will be no doubt that the evidence of mathematics, which has become the pattern and symbol of all evidence, rests essentially not upon demonstration, but upon immediate perception, which is thus here, as everywhere else, the ultimate ground and source of truth. Yet the perception which lies at the basis of mathematics has a great advantage over all other perception, and therefore over empirical perception. It is _a priori_, and therefore independent of experience, which is always given only in successive parts; therefore everything is equally near to it, and we can start either from the reason or from the consequent, as we please. Now this makes it absolutely reliable, for in it the consequent is known from the reason, and this is the only kind of knowledge that has necessity; for example, the equality of the sides is known as established by the equality of the angles. All empirical perception, on the other hand, and the greater part of experience, proceeds conversely from the consequent to the reason, and this kind of knowledge is not infallible, for necessity only attaches to the consequent on account of the reason being given, and no necessity attaches to the knowledge of the reason from the consequent, for the same consequent may follow from different reasons. The latter kind of knowledge is simply induction, _i.e._, from many consequents which point to one reason, the reason is accepted as certain; but as the cases can never be all before us, the truth here is not unconditionally certain. But all knowledge through sense-perception, and the great bulk of experience, has only this kind of truth. The affection of one of the senses induces the understanding to infer a cause of the effect, but, as a conclusion from the consequent to the reason is never certain, illusion, which is deception of the senses, is possible, and indeed often occurs, as was pointed out above. Only when several of the senses, or it may be all the five, receive impressions which point to the same cause, the possibility of illusion is reduced to a minimum; but yet it still exists, for there are cases, for example, the case of counterfeit money, in which all the senses are deceived. All empirical knowledge, and consequently the whole of natural science, is in the same position, except only the pure, or as Kant calls it, metaphysical part of it. Here also the causes are known from the effects, consequently all natural philosophy rests upon hypotheses, which are often false, and must then gradually give place to more correct ones. Only in the case of purposely arranged experiments, knowledge proceeds from the cause to the effect, that is, it follows the method that affords certainty; but these experiments themselves are undertaken in consequence of hypotheses. Therefore, no branch of natural science, such as physics, or astronomy, or physiology could be discovered all at once, as was the case with mathematics and logic, but required and requires the collected and compared experiences of many centuries. In the first place, repeated confirmation in experience brings the induction, upon which the hypothesis rests, so near completeness that in practice it takes the place of certainty, and is regarded as diminishing the value of the hypothesis, its source, just as little as the incommensurability of straight and curved lines diminishes the value of the application of geometry, or that perfect exactness of the logarithm, which is not attainable, diminishes the value of arithmetic. For as the logarithm, or the squaring of the circle, approaches infinitely near to correctness through infinite fractions, so, through manifold experience, the induction, _i.e._, the knowledge of the cause from the effects, approaches, not infinitely indeed, but yet so near mathematical evidence, _i.e._, knowledge of the effects from the cause, that the possibility of mistake is small enough to be neglected, but yet the possibility exists; for example, a conclusion from an indefinite number of cases to all cases, _i.e._, to the unknown ground on which all depend, is an induction. What conclusion of this kind seems more certain than that all men have the heart on the left side? Yet there are extremely rare and quite isolated exceptions of men who have the heart upon the right side. Sense-perception and empirical science have, therefore, the same kind of evidence. The advantage which mathematics, pure natural science, and logic have over them, as _a priori_ knowledge, rests merely upon this, that the formal element in knowledge upon which all that is _a priori_ is based, is given as a whole and at once, and therefore in it we can always proceed from the cause to the effect, while in the former kind of knowledge we are generally obliged to proceed from the effect to the cause. In other respects, the law of causality, or the principle of sufficient reason of change, which guides empirical knowledge, is in itself just as certain as the other forms of the principle of sufficient reason which are followed by the _a priori_ sciences referred to above. Logical demonstrations from concepts or syllogisms have the advantage of proceeding from the reason to the consequent, just as much as knowledge through perception _a priori_, and therefore in themselves, _i.e._, according to their form, they are infallible. This has greatly assisted to bring demonstration in general into such esteem. But this infallibility is merely relative; the demonstration merely subsumes under the first principles of the science, and it is these which contain the whole material truth of science, and they must not themselves be demonstrated, but must be founded on perception. In the few _a priori_ sciences we have named above, this perception is pure, but everywhere else it is empirical, and is only raised to universality through induction. If, then, in the empirical sciences also, the particular is proved from the general, yet the general, on the other hand, has received its truth from the particular; it is only a store of collected material, not a self-constituted foundation.

So much for the foundation of truth. Of the source and possibility of error many explanations have been tried since Plato’s metaphorical solution of the dove-cot where the wrong pigeons are caught, &c. (Theætetus, p. 167, _et seq._) Kant’s vague, indefinite explanation of the source of error by means of the diagram of diagonal motion, will be found in the “Critique of Pure Reason,” p. 294 of the first edition, and p. 350 of the fifth. As truth is the relation of a judgment to its ground of knowledge, it is always a problem how the person judging can believe that he has such a ground of knowledge and yet not have it; that is to say, how error, the deception of reason, is possible. I find this possibility quite analogous to that of illusion, or the deception of the understanding, which has been explained above. My opinion is (and this is what gives this explanation its proper place here) that _every error is an inference from the consequent to the reason_, which indeed is valid when we know that the consequent has that reason and can have no other; but otherwise is not valid. The person who falls into error, either attributes to a consequent a reason which it cannot have, in which case he shows actual deficiency of understanding, _i.e._, deficiency in the capacity for immediate knowledge of the connection between the cause and the effect, or, as more frequently happens, he attributes to the effect a cause which is possible, but he adds to the major proposition of the syllogism, in which he infers the cause from the effect, that this effect _always_ results only from this cause. Now he could only be assured of this by a complete induction, which, however, he assumes without having made it. This “always” is therefore too wide a concept, and instead of it he ought to have used “sometimes” or “generally.” The conclusion would then be problematical, and therefore not erroneous. That the man who errs should proceed in this way is due either to haste, or to insufficient knowledge of what is possible, on account of which he does not know the necessity of the induction that ought to be made. Error then is quite analogous to illusion. Both are inferences from the effect to the cause; the illusion brought about always in accordance with the law of causality, and by the understanding alone, thus directly, in perception itself; the error in accordance with all the forms of the principle of sufficient reason, and by the reason, thus in thought itself; yet most commonly in accordance with the law of causality, as will appear from the three following examples, which may be taken as types or representatives of the three kinds of error. (1.) The illusion of the senses (deception of the understanding) induces error (deception of the reason); for example, if one mistakes a painting for an alto-relief, and actually takes it for such; the error results from a conclusion from the following major premise: “If dark grey passes regularly through all shades to white; the cause is _always_ the light, which strikes differently upon projections and depressions, _ergo_—.” (2.) “If there is no money in my safe, the cause is _always_ that my servant has got a key for it: _ergo_—.” (3.) “If a ray of sunlight, broken through a prism, _i.e._, bent up or down, appears as a coloured band instead of round and white as before, the cause must always be that light consists of homogeneous rays, differently coloured and refrangible to different degrees, which, when forced asunder on account of the difference of their refrangibility, give an elongated and variously-coloured spectrum: _ergo—bibamus!_”—It must be possible to trace every error to such a conclusion, drawn from a major premise which is often only falsely generalised, hypothetical, and founded on the assumption that some particular cause is that of a certain effect. Only certain mistakes in counting are to be excepted, and they are not really errors, but merely mistakes. The operation prescribed by the concepts of the numbers has not been carried out in pure intuition or perception, in counting, but some other operation instead of it.

As regards the _content_ of the sciences generally, it is, in fact, always the relation of the phenomena of the world to each other, according to the principle of sufficient reason, under the guidance of the _why_, which has validity and meaning only through this principle. _Explanation_ is the establishment of this relation. Therefore explanation can never go further than to show two ideas standing to each other in the relation peculiar to that form of the principle of sufficient reason which reigns in the class to which they belong. If this is done we cannot further be asked the question, _why_: for the relation proved is that one which absolutely cannot be imagined as other than it is, _i.e._, it is the form of all knowledge. Therefore we do not ask why 2 + 2 = 4; or why the equality of the angles of a triangle determines the equality of the sides; or why its effect follows any given cause; or why the truth of the conclusion is evident from the truth of the premises. Every explanation which does not ultimately lead to a relation of which no “why” can further be demanded, stops at an accepted _qualitas occulta_; but this is the character of every original force of nature. Every explanation in natural science must ultimately end with such a _qualitas occulta_, and thus with complete obscurity. It must leave the inner nature of a stone just as much unexplained as that of a human being; it can give as little account of the weight, the cohesion, the chemical qualities, &c., of the former, as of the knowing and acting of the latter. Thus, for example, weight is a _qualitas occulta_, for it can be thought away, and does not proceed as a necessity from the form of knowledge; which, on the contrary, is not the case with the law of inertia, for it follows from the law of causality, and is therefore sufficiently explained if it is referred to that law. There are two things which are altogether inexplicable,—that is to say, do not ultimately lead to the relation which the principle of sufficient reason expresses. These are, first, the principle of sufficient reason itself in all its four forms, because it is the principle of all explanation, which has meaning only in relation to it; secondly, that to which this principle does not extend, but which is the original source of all phenomena; the thing-in-itself, the knowledge of which is not subject to the principle of sufficient reason. We must be content for the present not to understand this thing-in-itself, for it can only be made intelligible by means of the following book, in which we shall resume this consideration of the possible achievements of the sciences. But at the point at which natural science, and indeed every science, leaves things, because not only its explanation of them, but even the principle of this explanation, the principle of sufficient reason, does not extend beyond this point; there philosophy takes them up and treats them after its own method, which is quite distinct from the method of science. In my essay on the principle of sufficient reason, § 51, I have shown how in the different sciences the chief guiding clue is one or other form of that principle; and, in fact, perhaps the most appropriate classification of the sciences might be based upon this circumstance. Every explanation arrived at by the help of this clue is, as we have said, merely relative; it explains things in relation to each other, but something which indeed is presupposed is always left unexplained. In mathematics, for example, this is space and time; in mechanics, physics, and chemistry it is matter, qualities, original forces and laws of nature; in botany and zoology it is the difference of species, and life itself; in history it is the human race with all its properties of thought and will: in all it is that form of the principle of sufficient reason which is respectively applicable. It is peculiar to _philosophy_ that it presupposes nothing as known, but treats everything as equally external and a problem; not merely the relations of phenomena, but also the phenomena themselves, and even the principle of sufficient reason to which the other sciences are content to refer everything. In philosophy nothing would be gained by such a reference, as one member of the series is just as external to it as another; and, moreover, that kind of connection is just as much a problem for philosophy as what is joined together by it, and the latter again is just as much a problem after its combination has been explained as before it. For, as we have said, just what the sciences presuppose and lay down as the basis and the limits of their explanation, is precisely and peculiarly the problem of philosophy, which may therefore be said to begin where science ends. It cannot be founded upon demonstrations, for they lead from known principles to unknown, but everything is equally unknown and external to philosophy. There can be no principle in consequence of which the world with all its phenomena first came into existence, and therefore it is not possible to construct, as Spinoza wished, a philosophy which demonstrates _ex firmis principiis_. Philosophy is the most general rational knowledge, the first principles of which cannot therefore be derived from another principle still more general. The principle of contradiction establishes merely the agreement of concepts, but does not itself produce concepts. The principle of sufficient reason explains the connections of phenomena, but not the phenomena themselves; therefore philosophy cannot proceed upon these principles to seek a _causa efficiens_ or a _causa finalis_ of the whole world. My philosophy, at least, does not by any means seek to know _whence_ or _wherefore_ the world exists, but merely _what_ the world is. But the _why_ is here subordinated to the _what_, for it already belongs to the world, as it arises and has meaning and validity only through the form of its phenomena, the principle of sufficient reason. We might indeed say that every one knows what the world is without help, for he is himself that subject of knowledge of which the world is the idea; and so far this would be true. But that knowledge is empirical, is in the concrete; the task of philosophy is to reproduce this in the abstract to raise to permanent rational knowledge the successive changing perceptions, and in general, all that is contained under the wide concept of feeling and merely negatively defined as not abstract, distinct, rational knowledge. It must therefore consist of a statement in the abstract, of the nature of the whole world, of the whole, and of all the parts. In order then that it may not lose itself in the endless multitude of particular judgments, it must make use of abstraction and think everything individual in the universal, and its differences also in the universal. It must therefore partly separate and partly unite, in order to present to rational knowledge the whole manifold of the world generally, according to its nature, comprehended in a few abstract concepts. Through these concepts, in which it fixes the nature of the world, the whole individual must be known as well as the universal, the knowledge of both therefore must be bound together to the minutest point. Therefore the capacity for philosophy consists just in that in which Plato placed it, the knowledge of the one in the many, and the many in the one. Philosophy will therefore be a sum-total of general judgments, whose ground of knowledge is immediately the world itself in its entirety, without excepting anything; thus all that is to be found in human consciousness; it will be _a complete recapitulation, as it were, a reflection, of the world in abstract concepts_, which is only possible by the union of the essentially identical in _one_ concept and the relegation of the different to another. This task was already prescribed to philosophy by Bacon of Verulam when he said: _ea demum vera est philosophia, quae mundi ipsius voces fidelissime reddit, et veluti dictante mundo conscripta est, et nihil aliud est, quam ejusdem_ SIMULACRUM ET REFLECTIO, _neque addit quidquam de proprio, sed tantum iterat et resonat_ (De Augm. Scient., L. 2, c. 13). But we take this in a wider sense than Bacon could then conceive.

The agreement which all the sides and parts of the world have with each other, just because they belong to a whole, must also be found in this abstract copy of it. Therefore the judgments in this sum-total could to a certain extent be deduced from each other, and indeed always reciprocally so deduced. Yet to make the first judgment possible, they must all be present, and thus implied as prior to it in the knowledge of the world in the concrete, especially as all direct proof is more certain than indirect proof; their harmony with each other by virtue of which they come together into the unity of _one_ thought, and which arises from the harmony and unity of the world of perception itself, which is their common ground of knowledge, is not therefore to be made use of to establish them, as that which is prior to them, but is only added as a confirmation of their truth. This problem itself can only become quite clear in being solved.(23)

§ 16. After this full consideration of reason as a special faculty of knowledge belonging to man alone, and the results and phenomena peculiar to human nature brought about by it, it still remains for me to speak of reason, so far as it is the guide of human action, and in this respect may be called _practical_. But what there is to say upon this point has found its place elsewhere in the appendix to this work, where I controvert the existence of the so-called practical reason of Kant, which he (certainly very conveniently) explained as the immediate source of virtue, and as the seat of an absolute (_i.e._, fallen from heaven) imperative. The detailed and thorough refutation of this Kantian principle of morality I have given later in the “Fundamental Problems of Ethics.” There remains, therefore, but little for me to say here about the actual influence of reason, in the true sense of the word, upon action. At the commencement of our treatment of reason we remarked, in general terms, how much the action and behaviour of men differs from that of brutes, and that this difference is to be regarded as entirely due to the presence of abstract concepts in consciousness. The influence of these upon our whole existence is so penetrating and significant that, on account of them, we are related to the lower animals very much as those animals that see are related to those that have no eyes (certain larvae, worms, and zoophytes). Animals without eyes know only by touch what is immediately present to them in space, what comes into contact with them; those which see, on the contrary, know a wide circle of near and distant objects. In the same way the absence of reason confines the lower animals to the ideas of perception, _i.e._, the real objects which are immediately present to them in time; we, on the contrary, on account of knowledge in the abstract, comprehend not only the narrow actual present, but also the whole past and future, and the wide sphere of the possible; we view life freely on all its sides, and go far beyond the present and the actual. Thus what the eye is in space and for sensuous knowledge, reason is, to a certain extent, in time and for inner knowledge. But as the visibility of objects has its worth and meaning only in the fact that it informs us of their tangibility, so the whole worth of abstract knowledge always consists in its relation to what is perceived. Therefore men naturally attach far more worth to immediate and perceived knowledge than to abstract concepts, to that which is merely thought; they place empirical knowledge before logical. But this is not the opinion of men who live more in words than in deeds, who have seen more on paper and in books than in actual life, and who in their greatest degeneracy become pedants and lovers of the mere letter. Thus only is it conceivable that Leibnitz and Wolf and all their successors could go so far astray as to explain knowledge of perception, after the example of Duns Scotus, as merely confused abstract knowledge! To the honour of Spinoza, I must mention that his truer sense led him, on the contrary, to explain all general concepts as having arisen from the confusion of that which was known in perception (Eth. II., prop. 40, Schol. 1). It is also a result of perverted opinion that in mathematics the evidence proper to it was rejected, and logical evidence alone accepted; that everything in general which was not abstract knowledge was comprehended under the wide name of feeling, and consequently was little valued; and lastly that the Kantian ethics regarded the good will which immediately asserts itself upon knowledge of the circumstances, and guides to right and good action as mere feeling and emotion, and consequently as worthless and without merit, and would only recognise actions which proceed from abstract maxims as having moral worth.

The many-sided view of life as a whole which man, as distinguished from the lower animals, possesses through reason, may be compared to a geometrical, colourless, abstract, reduced plan of his actual life. He, therefore, stands to the lower animals as the navigator who, by means of chart, compass, and quadrant, knows accurately his course and his position at any time upon the sea, stands to the uneducated sailors who see only the waves and the heavens. Thus it is worth noticing, and indeed wonderful, how, besides his life in the concrete, man always lives another life in the abstract. In the former he is given as a prey to all the storms of actual life, and to the influence of the present; he must struggle, suffer, and die like the brute. But his life in the abstract, as it lies before his rational consciousness, is the still reflection of the former, and of the world in which he lives; it is just that reduced chart or plan to which we have referred. Here in the sphere of quiet deliberation, what completely possessed him and moved him intensely before, appears to him cold, colourless, and for the moment external to him; he is merely the spectator, the observer. In respect of this withdrawal into reflection he may be compared to an actor who has played his part in one scene, and who takes his place among the audience till it is time for him to go upon the stage again, and quietly looks on at whatever may happen, even though it be the preparation for his own death (in the piece), but afterwards he again goes on the stage and acts and suffers as he must. From this double life proceeds that quietness peculiar to human beings, so very different from the thoughtlessness of the brutes, and with which, in accordance with previous reflection, or a formed determination, or a recognised necessity, a man suffers or accomplishes in cold blood, what is of the utmost and often terrible importance to him; suicide, execution, the duel, enterprises of every kind fraught with danger to life, and, in general, things against which his whole animal nature rebels. Under such circumstances we see to what an extent reason has mastered the animal nature, and we say to the strong: σιδηρειον νυ τοι ἡτορ! (_ferreum certe tibi cor_), Il. 24, 521. Here we can say truly that reason manifests itself practically, and thus wherever action is guided by reason, where the motives are abstract concepts, wherever we are not determined by particular ideas of perception, nor by the impression of the moment which guides the brutes, there _practical reason_ shows itself. But I have fully explained in the Appendix, and illustrated by examples, that this is entirely different from and unrelated to the ethical worth of

## actions; that rational action and virtuous action are two entirely

different things; that reason may just as well find itself in connection with great evil as with great good, and by its assistance may give great power to the one as well as to the other; that it is equally ready and valuable for the methodical and consistent carrying out of the noble and of the bad intention, of the wise as of the foolish maxim; which all results from the constitution of its nature, which is feminine, receptive, retentive, and not spontaneous; all this I have shown in detail in the Appendix, and illustrated by examples. What is said there would have been placed here, but on account of my polemic against Kant’s pretended practical reason I have been obliged to relegate it to the Appendix, to which I therefore refer.

The ideal explained in the _Stoical philosophy_ is the most complete development of _practical reason_ in the true and genuine sense of the word; it is the highest summit to which man can attain by the mere use of his reason, and in it his difference from the brutes shows itself most distinctly. For the ethics of Stoicism are originally and essentially, not a doctrine of virtue, but merely a guide to a rational life, the end and aim of which is happiness through peace of mind. Virtuous conduct appears in it as it were merely by accident, as the means, not as the end. Therefore the ethical theory of Stoicism is in its whole nature and point of view fundamentally different from the ethical systems which lay stress directly upon virtue, such as the doctrines of the Vedas, of Plato, of Christianity, and of Kant. The aim of Stoical ethics is happiness: τελος το ευδαι μονειν (_virtutes omnes finem habere beatitudinem_) it is called in the account of the Stoa by Stobæus (Ecl., L. ii. c. 7, p. 114, and also p. 138). Yet the ethics of Stoicism teach that happiness can only be attained with certainty through inward peace and quietness of spirit (αταραξια), and that this again can only be reached through virtue; this is the whole meaning of the saying that virtue is the highest good. But if indeed by degrees the end is lost sight of in the means, and virtue is inculcated in a way which discloses an interest entirely different from that of one’s own happiness, for it contradicts this too distinctly; this is just one of those inconsistencies by means of which, in every system, the immediately known, or, as it is called, felt truth leads us back to the right way in defiance of syllogistic reasoning; as, for example, we see clearly in the ethical teaching of Spinoza, which deduces a pure doctrine of virtue from the egoistical _suum utile quærere_ by means of palpable sophisms. According to this, as I conceive the spirit of the Stoical ethics, their source lies in the question whether the great prerogative of man, reason, which, by means of planned action and its results, relieves life and its burdens so much, might not also be capable of freeing him at once, directly, _i.e._, through mere knowledge, completely, or nearly so, of the sorrows and miseries of every kind of which his life is full. They held that it was not in keeping with the prerogative of reason that the nature given with it, which by means of it comprehends and contemplates an infinity of things and circumstances, should yet, through the present, and the accidents that can be contained in the few years of a life that is short, fleeting, and uncertain, be exposed to such intense pain, to such great anxiety and suffering, as arise from the tempestuous strain of the desires and the antipathies; and they believed that the due application of reason must raise men above them, and can make them invulnerable. Therefore Antisthenes says: Δει κτασθαι νουν, η βροχον (_aut mentem parandam, aut laqueum._ Plut. de stoic. repugn., c. 14), _i.e._, life is so full of troubles and vexations, that one must either rise above it by means of corrected thoughts, or leave it. It was seen that want and suffering did not directly and of necessity spring from not having, but from desiring to have and not having; that therefore this desire to have is the necessary condition under which alone it becomes a privation not to have and begets pain. Ου πενια λυπην εργαζεται, αλλα επιθυμια (_non paupertas dolorem efficit, sed cupiditas_), Epict., fragm. 25. Men learned also from experience that it is only the hope of what is claimed that begets and nourishes the wish; therefore neither the many unavoidable evils which are common to all, nor unattainable blessings, disquiet or trouble us, but only the trifling more or less of those things which we can avoid or attain; indeed, not only what is absolutely unavoidable or unattainable, but also what is merely relatively so, leaves us quite undisturbed; therefore the ills that have once become joined to our individuality, or the good things that must of necessity always be denied us, are treated with indifference, in accordance with the peculiarity of human nature that every wish soon dies and can no more beget pain if it is not nourished by hope. It followed from all this that happiness always depends upon the proportion between our claims and what we receive. It is all one whether the quantities thus related be great or small, and the proportion can be established just as well by diminishing the amount of the first as by increasing the amount of the second; and in the same way it also follows that all suffering proceeds from the want of proportion between what we demand and expect and what we get. Now this want of proportion obviously lies only in knowledge, and it could be entirely abolished through fuller insight.(24) Therefore Chrysippus says: δει ζῃν κατ᾽ εμπειριαν των φυσει συμβαινοντων (Stob. Ecl., L. ii. c. 7, p. 134), that is, one ought to live with a due knowledge of the transitory nature of the things of the world. For as often as a man loses self-command, or is struck down by a misfortune, or grows angry, or becomes faint-hearted, he shows that he finds things different from what he expected, consequently that he was caught in error, and did not know the world and life, did not know that the will of the individual is crossed at every step by the chance of inanimate nature and the antagonism of aims and the wickedness of other individuals: he has therefore either not made use of his reason in order to arrive at a general knowledge of this characteristic of life, or he lacks judgment, in that he does not recognise in the particular what he knows in general, and is therefore surprised by it and loses his self-command.(25) Thus also every keen pleasure is an error and an illusion, for no attained wish can give lasting satisfaction; and, moreover, every possession and every happiness is but lent by chance for an uncertain time, and may therefore be demanded back the next hour. All pain rests on the passing away of such an illusion; thus both arise from defective knowledge; the wise man therefore holds himself equally aloof from joy and sorrow, and no event disturbs his αταραξια.

In accordance with this spirit and aim of the Stoa, Epictetus began and ended with the doctrine as the kernel of his philosophy, that we should consider well and distinguish what depends upon us and what does not, and therefore entirely avoid counting upon the latter, whereby we shall certainly remain free from all pain, sorrow, and anxiety. But that which alone is dependent upon us is the will; and here a transition gradually takes place to a doctrine of virtue, for it is observed that as the outer world, which is independent of us, determines good and bad fortune, so inner contentment with ourselves, or the absence of it, proceeds from the will. But it was then asked whether we ought to apply the words _bonum_ and _malum_ to the two former or to the two latter? This was indeed arbitrary and a matter of choice, and did not make any real difference, but yet the Stoics disputed everlastingly with the Peripatetics and Epicureans about it, and amused themselves with the inadmissible comparison of two entirely incommensurable quantities, and the antithetical, paradoxical judgments which proceeded from them, and which they flung at each other. The _Paradoxa_ of Cicero afford us an interesting collection of these from the Stoical side.

Zeno, the founder, seems originally to have followed a somewhat different path. The starting-point with him was that for the attainment of the highest good, _i.e._, blessedness and spiritual peace, one must live in harmony with oneself (ὁμολογουμενους ξῃν; δ᾽ εστι καθ᾽ ἑνα λογον και συμφωνον ξῃν.—_Consonanter vivere: hoc est secundum unam rationem et concordem sibi vivere._ Stob. Ecl. eth. L. ii., c. 7, p. 132. Also: Αρετην διαθεσιν ειναι ψυχης συμφωνον ἑαυτῃ περι ὁλον τον βιον. _Virtutem esse animi affectiomem secum per totam vitam consentientem_, _ibid._, p. 104.) Now this was only possible for a man if he determined himself entirely rationally, according to concepts, not according to changing impressions and moods; since, however, only the maxims of our conduct, not the consequences nor the outward circumstances, are in our power, in order to be always consistent we must set before us as our aim only the maxims and not the consequences and circumstances, and thus again a doctrine of virtue is introduced.

But the ethical principle of Zeno—to live in harmony with oneself—appeared even to his immediate successors to be too formal and empty. They therefore gave it material content by the addition—“to live in harmony with nature” (ὁμολογουμενως τῃ φυσει ζῃν), which, as Stobæus mentions in another place, was first added by Kleanthes, and extended the matter very much on account of the wide sphere of the concept and the vagueness of the expression. For Kleanthes meant the whole of nature in general, while Chrysippus meant human nature in particular (Diog. Laert., 7, 89). It followed that what alone was adapted to the latter was virtue, just as the satisfaction of animal desires was adapted to animal natures; and thus ethics had again to be forcibly united to a doctrine of virtue, and in some way or other established through physics. For the Stoics always aimed at unity of principle, as for them God and the world were not dissevered.

The ethical system of Stoicism, regarded as a whole, is in fact a very valuable and estimable attempt to use the great prerogative of man, reason, for an important and salutary end; to raise him above the suffering and pain to which all life is exposed, by means of a maxim—

“_Qua ratione queas traducere leniter œvum:_ _Ne te semper inops agitet vexetque cupido,_ _Ne pavor et rerum mediocriter utilium spes,_”

and thus to make him partake, in the highest degree, of the dignity which belongs to him as a rational being, as distinguished from the brutes; a dignity of which, in this sense at any rate, we can speak, though not in any other. It is a consequence of my view of the ethical system of Stoicism that it must be explained at the part of my work at which I consider what reason is and what it can do. But although it may to a certain extent be possible to attain that end through the application of reason, and through a purely rational system of ethics, and although experience shows that the happiest men are those purely rational characters commonly called practical philosophers,—and rightly so, because just as the true, that is, the theoretical philosopher carries life into the concept, they carry the concept into life,—yet it is far from the case that perfection can be attained in this way, and that the reason, rightly used, can really free us from the burden and sorrow of life, and lead us to happiness. Rather, there lies an absolute contradiction in wishing to live without suffering, and this contradiction is also implied in the commonly used expression, “blessed life.” This will become perfectly clear to whoever comprehends the whole of the following exposition. In this purely rational system of ethics the contradiction reveals itself thus, the Stoic is obliged in his doctrine of the way to the blessed life (for that is what his ethical system always remains) to insert a recommendation of suicide (as among the magnificent ornaments and apparel of Eastern despots there is always a costly vial of poison) for the case in which the sufferings of the body, which cannot be philosophised away by any principles or syllogistic reasonings, are paramount and incurable; thus its one aim, blessedness, is rendered vain, and nothing remains as a mode of escape from suffering except death; in such a case then death must be voluntarily accepted, just as we would take any other medicine. Here then a marked antagonism is brought out between the ethical system of Stoicism and all those systems referred to above which make virtue in itself directly, and accompanied by the most grievous sorrows, their aim, and will not allow a man to end his life in order to escape from suffering. Not one of them, however, was able to give the true reason for the rejection of suicide, but they laboriously collected illusory explanations from all sides: the true reason will appear in the Fourth Book in the course of the development of our system. But the antagonism referred to reveals and establishes the essential difference in fundamental principle between Stoicism, which is just a special form of endæmonism, and those doctrines we have mentioned, although both are often at one in their results, and are apparently related. And the inner contradiction referred to above, with which the ethical system of Stoicism is affected even in its fundamental thought, shows itself further in the circumstance that its ideal, the Stoic philosopher, as the system itself represents him, could never obtain life or inner poetic truth, but remains a wooden, stiff lay-figure of which nothing can be made. He cannot himself make use of his wisdom, and his perfect peace, contentment, and blessedness directly contradict the nature of man, and preclude us from forming any concrete idea of him. When compared with him, how entirely different appear the overcomers of the world, and voluntary hermits that Indian philosophy presents to us, and has actually produced; or indeed, the holy man of Christianity, that excellent form full of deep life, of the greatest poetic truth, and the highest significance, which stands before us in perfect virtue, holiness, and sublimity, yet in a state of supreme suffering.(26)

SECOND BOOK. THE WORLD AS WILL.

First Aspect. The Objectification Of The Will.

Nos habitat, non tartara, sed nec sidera coeli: Spiritus, in nobis qui viget, illa facit.

§ 17. In the first book we considered the idea merely as such, that is, only according to its general form. It is true that as far as the abstract idea, the concept, is concerned, we obtained a knowledge of it in respect of its content also, because it has content and meaning only in relation to the idea of perception, without which it would be worthless and empty. Accordingly, directing our attention exclusively to the idea of perception, we shall now endeavour to arrive at a knowledge of its content, its more exact definition, and the forms which it presents to us. And it will specially interest us to find an explanation of its peculiar significance, that significance which is otherwise merely felt, but on account of which it is that these pictures do not pass by us entirely strange and meaningless, as they must otherwise do, but speak to us directly, are understood, and obtain an interest which concerns our whole nature.

We direct our attention to mathematics, natural science, and philosophy, for each of these holds out the hope that it will afford us a part of the explanation we desire. Now, taking philosophy first, we find that it is like a monster with many heads, each of which speaks a different language. They are not, indeed, all at variance on the point we are here considering, the significance of the idea of perception. For, with the exception of the Sceptics and the Idealists, the others, for the most part, speak very much in the same way of an _object_ which constitutes the _basis_ of the idea, and which is indeed different in its whole being and nature from the idea, but yet is in all points as like it as one egg is to another. But this does not help us, for we are quite unable to distinguish such an object from the idea; we find that they are one and the same; for every object always and for ever presupposes a subject, and therefore remains idea, so that we recognised objectivity as belonging to the most universal form of the idea, which is the division into subject and object. Further, the principle of sufficient reason, which is referred to in support of this doctrine, is for us merely the form of the idea, the orderly combination of one idea with another, but not the combination of the whole finite or infinite series of ideas with something which is not idea at all, and which cannot therefore be presented in perception. Of the Sceptics and Idealists we spoke above, in examining the controversy about the reality of the outer world.

If we turn to mathematics to look for the fuller knowledge we desire of the idea of perception, which we have, as yet, only understood generally, merely in its form, we find that mathematics only treats of these ideas so far as they fill time and space, that is, so far as they are quantities. It will tell us with the greatest accuracy the how-many and the how-much; but as this is always merely relative, that is to say, merely a comparison of one idea with others, and a comparison only in the one respect of quantity, this also is not the information we are principally in search of.

Lastly, if we turn to the wide province of natural science, which is divided into many fields, we may, in the first place, make a general division of it into two parts. It is either the description of forms, which I call _Morphology_, or the explanation of changes, which I call _Etiology_. The first treats of the permanent forms, the second of the changing matter, according to the laws of its transition from one form to another. The first is the whole extent of what is generally called natural history. It teaches us, especially in the sciences of botany and zoology, the various permanent, organised, and therefore definitely determined forms in the constant change of individuals; and these forms constitute a great part of the content of the idea of perception. In natural history they are classified, separated, united, arranged according to natural and artificial systems, and brought under concepts which make a general view and knowledge of the whole of them possible. Further, an infinitely fine analogy both in the whole and in the parts of these forms, and running through them all (_unité de plan_), is established, and thus they may be compared to innumerable variations on a theme which is not given. The passage of matter into these forms, that is to say, the origin of individuals, is not a special part of natural science, for every individual springs from its like by generation, which is everywhere equally mysterious, and has as yet evaded definite knowledge. The little that is known on the subject finds its place in physiology, which belongs to that part of natural science I have called etiology. Mineralogy also, especially where it becomes geology, inclines towards etiology, though it principally belongs to morphology. Etiology proper comprehends all those branches of natural science in which the chief concern is the knowledge of cause and effect. The sciences teach how, according to an invariable rule, one condition of matter is necessarily followed by a certain other condition; how one change necessarily conditions and brings about a certain other change; this sort of teaching is called _explanation_. The principal sciences in this department are mechanics, physics, chemistry, and physiology.

If, however, we surrender ourselves to its teaching, we soon become convinced that etiology cannot afford us the information we chiefly desire, any more than morphology. The latter presents to us innumerable and infinitely varied forms, which are yet related by an unmistakable family likeness. These are for us ideas, and when only treated in this way, they remain always strange to us, and stand before us like hieroglyphics which we do not understand. Etiology, on the other hand, teaches us that, according to the law of cause and effect, this particular condition of matter brings about that other particular condition, and thus it has explained it and performed its part. However, it really does nothing more than indicate the orderly arrangement according to which the states of matter appear in space and time, and teach in all cases what phenomenon must necessarily appear at a particular time in a particular place. It thus determines the position of phenomena in time and space, according to a law whose special content is derived from experience, but whose universal form and necessity is yet known to us independently of experience. But it affords us absolutely no information about the inner nature of any one of these phenomena: this is called a _force of nature_, and it lies outside the province of causal explanation, which calls the constant uniformity with which manifestations of such a force appear whenever their known conditions are present, a _law of nature_. But this law of nature, these conditions, and this appearance in a particular place at a particular time, are all that it knows or ever can know. The force itself which manifests itself, the inner nature of the phenomena which appear in accordance with these laws, remains always a secret to it, something entirely strange and unknown in the case of the simplest as well as of the most complex phenomena. For although as yet etiology has most completely achieved its aim in mechanics, and least completely in physiology, still the force on account of which a stone falls to the ground or one body repels another is, in its inner nature, not less strange and mysterious than that which produces the movements and the growth of an animal. The science of mechanics presupposes matter, weight, impenetrability, the possibility of communicating motion by impact, inertia and so forth as ultimate facts, calls them forces of nature, and their necessary and orderly appearance under certain conditions a law of nature. Only after this does its explanation begin, and it consists in indicating truly and with mathematical exactness, how, where and when each force manifests itself, and in referring every phenomenon which presents itself to the operation of one of these forces. Physics, chemistry, and physiology proceed in the same way in their province, only they presuppose more and accomplish less. Consequently the most complete etiological explanation of the whole of nature can never be more than an enumeration of forces which cannot be explained, and a reliable statement of the rule according to which phenomena appear in time and space, succeed, and make way for each other. But the inner nature of the forces which thus appear remains unexplained by such an explanation, which must confine itself to phenomena and their arrangement, because the law which it follows does not extend further. In this respect it may be compared to a section of a piece of marble which shows many veins beside each other, but does not allow us to trace the course of the veins from the interior of the marble to its surface. Or, if I may use an absurd but more striking comparison, the philosophical investigator must always have the same feeling towards the complete etiology of the whole of nature, as a man who, without knowing how, has been brought into a company quite unknown to him, each member of which in turn presents another to him as his friend and cousin, and therefore as quite well known, and yet the man himself, while at each introduction he expresses himself gratified, has always the question on his lips: “But how the deuce do I stand to the whole company?”

Thus we see that, with regard to those phenomena which we know only as our ideas, etiology can never give us the desired information that shall carry us beyond this point. For, after all its explanations, they still remain quite strange to us, as mere ideas whose significance we do not understand. The causal connection merely gives us the rule and the relative order of their appearance in space and time, but affords us no further knowledge of that which so appears. Moreover, the law of causality itself has only validity for ideas, for objects of a definite class, and it has meaning only in so far as it presupposes them. Thus, like these objects themselves, it always exists only in relation to a subject, that is, conditionally; and so it is known just as well if we start from the subject, _i.e._, _a priori_, as if we start from the object, _i.e._, _a posteriori_. Kant indeed has taught us this.

But what now impels us to inquiry is just that we are not satisfied with knowing that we have ideas, that they are such and such, and that they are connected according to certain laws, the general expression of which is the principle of sufficient reason. We wish to know the significance of these ideas; we ask whether this world is merely idea; in which case it would pass by us like an empty dream or a baseless vision, not worth our notice; or whether it is also something else, something more than idea, and if so, what. Thus much is certain, that this something we seek for must be completely and in its whole nature different from the idea; that the forms and laws of the idea must therefore be completely foreign to it; further, that we cannot arrive at it from the idea under the guidance of the laws which merely combine objects, ideas, among themselves, and which are the forms of the principle of sufficient reason.

Thus we see already that we can never arrive at the real nature of things from without. However much we investigate, we can never reach anything but images and names. We are like a man who goes round a castle seeking in vain for an entrance, and sometimes sketching the façades. And yet this is the method that has been followed by all philosophers before me.

§ 18. In fact, the meaning for which we seek of that world which is present to us only as our idea, or the transition from the world as mere idea of the knowing subject to whatever it may be besides this, would never be found if the investigator himself were nothing more than the pure knowing subject (a winged cherub without a body). But he is himself rooted in that world; he finds himself in it as an _individual_, that is to say, his knowledge, which is the necessary supporter of the whole world as idea, is yet always given through the medium of a body, whose affections are, as we have shown, the starting-point for the understanding in the perception of that world. His body is, for the pure knowing subject, an idea like every other idea, an object among objects. Its movements and

## actions are so far known to him in precisely the same way as the changes

of all other perceived objects, and would be just as strange and incomprehensible to him if their meaning were not explained for him in an entirely different way. Otherwise he would see his actions follow upon given motives with the constancy of a law of nature, just as the changes of other objects follow upon causes, stimuli, or motives. But he would not understand the influence of the motives any more than the connection between every other effect which he sees and its cause. He would then call the inner nature of these manifestations and actions of his body which he did not understand a force, a quality, or a character, as he pleased, but he would have no further insight into it. But all this is not the case; indeed the answer to the riddle is given to the subject of knowledge who appears as an individual, and the answer is _will_. This and this alone gives him the key to his own existence, reveals to him the significance, shows him the inner mechanism of his being, of his action, of his movements. The body is given in two entirely different ways to the subject of knowledge, who becomes an individual only through his identity with it. It is given as an idea in intelligent perception, as an object among objects and subject to the laws of objects. And it is also given in quite a different way as that which is immediately known to every one, and is signified by the word _will_. Every true act of his will is also at once and without exception a movement of his body. The act of will and the movement of the body are not two different things objectively known, which the bond of causality unites; they do not stand in the relation of cause and effect; they are one and the same, but they are given in entirely different ways,—immediately, and again in perception for the understanding. The action of the body is nothing but the act of the will objectified, _i.e._, passed into perception. It will appear later that this is true of every movement of the body, not merely those which follow upon motives, but also involuntary movements which follow upon mere stimuli, and, indeed, that the whole body is nothing but objectified will, _i.e._, will become idea. All this will be proved and made quite clear in the course of this work. In one respect, therefore, I shall call the body the _objectivity of will_; as in the previous book, and in the essay on the principle of sufficient reason, in accordance with the one-sided point of view intentionally adopted there (that of the idea), I called it _the immediate object_. Thus in a certain sense we may also say that will is the knowledge _a priori_ of the body, and the body is the knowledge _a posteriori_ of the will. Resolutions of the will which relate to the future are merely deliberations of the reason about what we shall will at a particular time, not real acts of will. Only the carrying out of the resolve stamps it as will, for till then it is never more than an intention that may be changed, and that exists only in the reason _in abstracto_. It is only in reflection that to will and to act are different; in reality they are one. Every true, genuine, immediate act of will is also, at once and immediately, a visible act of the body. And, corresponding to this, every impression upon the body is also, on the other hand, at once and immediately an impression upon the will. As such it is called pain when it is opposed to the will; gratification or pleasure when it is in accordance with it. The degrees of both are widely different. It is quite wrong, however, to call pain and pleasure ideas, for they are by no means ideas, but immediate affections of the will in its manifestation, the body; compulsory, instantaneous willing or not-willing of the impression which the body sustains. There are only a few impressions of the body which do not touch the will, and it is through these alone that the body is an immediate object of knowledge, for, as perceived by the understanding, it is already an indirect object like all others. These impressions are, therefore, to be treated directly as mere ideas, and excepted from what has been said. The impressions we refer to are the affections of the purely objective senses of sight, hearing, and touch, though only so far as these organs are affected in the way which is specially peculiar to their specific nature. This affection of them is so excessively weak an excitement of the heightened and specifically modified sensibility of these parts that it does not affect the will, but only furnishes the understanding with the data out of which the perception arises, undisturbed by any excitement of the will. But every stronger or different kind of affection of these organs of sense is painful, that is to say, against the will, and thus they also belong to its objectivity. Weakness of the nerves shows itself in this, that the impressions which have only such a degree of strength as would usually be sufficient to make them data for the understanding reach the higher degree at which they influence the will, that is to say, give pain or pleasure, though more often pain, which is, however, to some extent deadened and inarticulate, so that not only particular tones and strong light are painful to us, but there ensues a generally unhealthy and hypochondriacal disposition which is not distinctly understood. The identity of the body and the will shows itself further, among other ways, in the circumstance that every vehement and excessive movement of the will, _i.e._, every emotion, agitates the body and its inner constitution directly, and disturbs the course of its vital functions. This is shown in detail in “Will in Nature,” p. 27 of the second edition and p. 28 of the third.

Lastly, the knowledge which I have of my will, though it is immediate, cannot be separated from that which I have of my body. I know my will, not as a whole, not as a unity, not completely, according to its nature, but I know it only in its particular acts, and therefore in time, which is the form of the phenomenal aspect of my body, as of every object. Therefore the body is a condition of the knowledge of my will. Thus, I cannot really imagine this will apart from my body. In the essay on the principle of sufficient reason, the will, or rather the subject of willing, is treated as a special class of ideas or objects. But even there we saw this object become one with the subject; that is, we saw it cease to be an object. We there called this union the miracle κατ᾽ εξοχην, and the whole of the present work is to a certain extent an explanation of this. So far as I know my will specially as object, I know it as body. But then I am again at the first class of ideas laid down in that essay, _i.e._, real objects. As we proceed we shall see always more clearly that these ideas of the first class obtain their explanation and solution from those of the fourth class given in the essay, which could no longer be properly opposed to the subject as object, and that, therefore, we must learn to understand the inner nature of the law of causality which is valid in the first class, and of all that happens in accordance with it from the law of motivation which governs the fourth class.

The identity of the will and the body, of which we have now given a cursory explanation, can only be proved in the manner we have adopted here. We have proved this identity for the first time, and shall do so more and more fully in the course of this work. By “proved” we mean raised from the immediate consciousness, from knowledge in the concrete to abstract knowledge of the reason, or carried over into abstract knowledge. On the other hand, from its very nature it can never be demonstrated, that is, deduced as indirect knowledge from some other more direct knowledge, just because it is itself the most direct knowledge; and if we do not apprehend it and stick to it as such, we shall expect in vain to receive it again in some indirect way as derivative knowledge. It is knowledge of quite a special kind, whose truth cannot therefore properly be brought under any of the four rubrics under which I have classified all truth in the essay on the principle of sufficient reason, § 29, the logical, the empirical, the metaphysical, and the metalogical, for it is not, like all these, the relation of an abstract idea to another idea, or to the necessary form of perceptive or of abstract ideation, but it is the relation of a judgment to the connection which an idea of perception, the body, has to that which is not an idea at all, but something _toto genere_ different, will. I should like therefore to distinguish this from all other truth, and call it κατ᾽ εξοχην _philosophical truth_. We can turn the expression of this truth in different ways and say: My body and my will are one;—or, What as an idea of perception I call my body, I call my will, so far as I am conscious of it in an entirely different way which cannot be compared to any other;—or, My body is the _objectivity_ of my will;—or, My body considered apart from the fact that it is my idea is still my will, and so forth.(27)

§ 19. In the first book we were reluctantly driven to explain the human body as merely idea of the subject which knows it, like all the other objects of this world of perception. But it has now become clear that what enables us consciously to distinguish our own body from all other objects which in other respects are precisely the same, is that our body appears in consciousness in quite another way _toto genere_ different from idea, and this we denote by the word _will_; and that it is just this double knowledge which we have of our own body that affords us information about it, about its action and movement following on motives, and also about what it experiences by means of external impressions; in a word, about what it is, not as idea, but as more than idea; that is to say, what it is _in itself_. None of this information have we got directly with regard to the nature, action, and experience of other real objects.

It is just because of this special relation to one body that the knowing subject is an individual. For regarded apart from this relation, his body is for him only an idea like all other ideas. But the relation through which the knowing subject is an _individual_, is just on that account a relation which subsists only between him and one particular idea of all those which he has. Therefore he is conscious of this _one_ idea, not merely as an idea, but in quite a different way as a will. If, however, he abstracts from that special relation, from that twofold and completely heterogeneous knowledge of what is one and the same, then that _one_, the body, is an idea like all other ideas. Therefore, in order to understand the matter, the individual who knows must either assume that what distinguishes that one idea from others is merely the fact that his knowledge stands in this double relation to it alone; that insight in two ways at the same time is open to him only in the case of this one object of perception, and that this is to be explained not by the difference of this object from all others, but only by the difference between the relation of his knowledge to this one object, and its relation to all other objects. Or else he must assume that this object is essentially different from all others; that it alone of all objects is at once both will and idea, while the rest are only ideas, _i.e._, only phantoms. Thus he must assume that his body is the only real individual in the world, _i.e._, the only phenomenon of will and the only immediate object of the subject. That other objects, considered merely as _ideas_, are like his body, that is, like it, fill space (which itself can only be present as idea), and also, like it, are causally active in space, is indeed demonstrably certain from the law of causality which is _a priori_ valid for ideas, and which admits of no effect without a cause; but apart from the fact that we can only reason from an effect to a cause generally, and not to a similar cause, we are still in the sphere of mere ideas, in which alone the law of causality is valid, and beyond which it can never take us. But whether the objects known to the individual only as ideas are yet, like his own body, manifestations of a will, is, as was said in the First Book, the proper meaning of the question as to the reality of the external world. To deny this is _theoretical egoism_, which on that account regards all phenomena that are outside its own will as phantoms, just as in a practical reference exactly the same thing is done by practical egoism. For in it a man regards and treats himself alone as a person, and all other persons as mere phantoms. Theoretical egoism can never be demonstrably refuted, yet in philosophy it has never been used otherwise than as a sceptical sophism, _i.e._, a pretence. As a serious conviction, on the other hand, it could only be found in a madhouse, and as such it stands in need of a cure rather than a refutation. We do not therefore combat it any further in this regard, but treat it as merely the last stronghold of scepticism, which is always polemical. Thus our knowledge, which is always bound to individuality and is limited by this circumstance, brings with it the necessity that each of us can only _be one_, while, on the other hand, each of us can _know all_; and it is this limitation that creates the need for philosophy. We therefore who, for this very reason, are striving to extend the limits of our knowledge through philosophy, will treat this sceptical argument of theoretical egoism which meets us, as an army would treat a small frontier fortress. The fortress cannot indeed be taken, but the garrison can never sally forth from it, and therefore we pass it by without danger, and are not afraid to have it in our rear.

The double knowledge which each of us has of the nature and activity of his own body, and which is given in two completely different ways, has now been clearly brought out. We shall accordingly make further use of it as a key to the nature of every phenomenon in nature, and shall judge of all objects which are not our own bodies, and are consequently not given to our consciousness in a double way but only as ideas, according to the analogy of our own bodies, and shall therefore assume that as in one aspect they are idea, just like our bodies, and in this respect are analogous to them, so in another aspect, what remains of objects when we set aside their existence as idea of the subject, must in its inner nature be the same as that in us which we call _will_. For what other kind of existence or reality should we attribute to the rest of the material world? Whence should we take the elements out of which we construct such a world? Besides will and idea nothing is known to us or thinkable. If we wish to attribute the greatest known reality to the material world which exists immediately only in our idea, we give it the reality which our own body has for each of us; for that is the most real thing for every one. But if we now analyse the reality of this body and its actions, beyond the fact that it is idea, we find nothing in it except the will; with this its reality is exhausted. Therefore we can nowhere find another kind of reality which we can attribute to the material world. Thus if we hold that the material world is something more than merely our idea, we must say that besides being idea, that is, in itself and according to its inmost nature, it is that which we find immediately in ourselves as _will_. I say according to its inmost nature; but we must first come to know more accurately this real nature of the will, in order that we may be able to distinguish from it what does not belong to itself, but to its manifestation, which has many grades. Such, for example, is the circumstance of its being accompanied by knowledge, and the determination by motives which is conditioned by this knowledge. As we shall see farther on, this does not belong to the real nature of will, but merely to its distinct manifestation as an animal or a human being. If, therefore, I say,—the force which attracts a stone to the earth is according to its nature, in itself, and apart from all idea, will, I shall not be supposed to express in this proposition the insane opinion that the stone moves itself in accordance with a known motive, merely because this is the way in which will appears in man.(28) We shall now proceed more clearly and in detail to prove, establish, and develop to its full extent what as yet has only been provisionally and generally explained.(29)

§ 20. As we have said, the will proclaims itself primarily in the voluntary movements of our own body, as the inmost nature of this body, as that which it is besides being object of perception, idea. For these voluntary movements are nothing else than the visible aspect of the individual acts of will, with which they are directly coincident and identical, and only distinguished through the form of knowledge into which they have passed, and in which alone they can be known, the form of idea.

But these acts of will have always a ground or reason outside themselves in motives. Yet these motives never determine more than what I will at _this_ time, in _this_ place, and under _these_ circumstances, not _that_ I will in general, or _what_ I will in general, that is, the maxims which characterise my volition generally. Therefore the inner nature of my volition cannot be explained from these motives; but they merely determine its manifestation at a given point of time: they are merely the occasion of my will showing itself; but the will itself lies outside the province of the law of motivation, which determines nothing but its appearance at each point of time. It is only under the presupposition of my empirical character that the motive is a sufficient ground of explanation of my

## action. But if I abstract from my character, and then ask, why, in

general, I will this and not that, no answer is possible, because it is only the manifestation of the will that is subject to the principle of sufficient reason, and not the will itself, which in this respect is to be called _groundless_. At this point I presuppose Kant’s doctrine of the empirical and intelligible character, and also my own treatment of the subject in “The Fundamental Problems of Ethics,” pp. 48, 58, and 178, _et seq._, of first edition (p. 174, _et seq._, of second edition). I shall also have to speak more fully on the question in the Fourth Book. For the present, I have only to draw attention to this, that the fact of one manifestation being established through another, as here the deed through the motive, does not at all conflict with the fact that its real nature is will, which itself has no _ground_; for as the principle of sufficient reason in all its aspects is only the form of knowledge, its validity extends only to the idea, to the phenomena, to the visibility of the will, but not to the will itself, which becomes visible.

If now every action of my body is the manifestation of an act of will in which my will itself in general, and as a whole, thus my character, expresses itself under given motives, manifestation of the will must be the inevitable condition and presupposition of every action. For the fact of its manifestation cannot depend upon something which does not exist directly and only through it, which consequently is for it merely accidental, and through which its manifestation itself would be merely accidental. Now that condition is just the whole body itself. Thus the body itself must be manifestation of the will, and it must be related to my will as a whole, that is, to my intelligible character, whose phenomenal appearance in time is my empirical character, as the particular

## action of the body is related to the particular act of the will. The whole

body, then, must be simply my will become visible, must be my will itself, so far as this is object of perception, an idea of the first class. It has already been advanced in confirmation of this that every impression upon my body also affects my will at once and immediately, and in this respect is called pain or pleasure, or, in its lower degrees, agreeable or disagreeable sensation; and also, conversely, that every violent movement of the will, every emotion or passion, convulses the body and disturbs the course of its functions. Indeed we can also give an etiological account, though a very incomplete one, of the origin of my body, and a somewhat better account of its development and conservation, and this is the substance of physiology. But physiology merely explains its theme in precisely the same way as motives explain action. Thus the physiological explanation of the functions of the body detracts just as little from the philosophical truth that the whole existence of this body and the sum total of its functions are merely the objectification of that will which appears in its outward actions in accordance with a motive, as the establishment of the individual action through the motive and the necessary sequence of the action from the motive conflicts with the fact that action in general, and according to its nature, is only the manifestation of a will which itself has no ground. If, however, physiology tries to refer even these outward actions, the immediate voluntary movements, to causes in the organism,—for example, if it explains the movement of the muscles as resulting from the presence of fluids (“like the contraction of a cord when it is wet,” says Reil in his “Archiv für Physiologie,” vol. vi. p. 153), even supposing it really could give a thorough explanation of this kind, yet this would never invalidate the immediately certain truth that every voluntary motion (_functiones animales_) is the manifestation of an act of will. Now, just as little can the physiological explanation of vegetative life (_functiones naturales vitales_), however far it may advance, ever invalidate the truth that the whole animal life which thus develops itself is the manifestation of will. In general, then, as we have shown above, no etiological explanation can ever give us more than the necessarily determined position in time and space of a particular manifestation, its necessary appearance there, according to a fixed law; but the inner nature of everything that appears in this way remains wholly inexplicable, and is presupposed by every etiological explanation, and merely indicated by the names, force, or law of nature, or, if we are speaking of action, character or will. Thus, although every particular action, under the presupposition of the definite character, necessarily follows from the given motive, and although growth, the process of nourishment, and all the changes of the animal body take place according to necessarily acting causes (stimuli), yet the whole series of actions, and consequently every individual act, and also its condition, the whole body itself which accomplishes it, and therefore also the process through which and in which it exists, are nothing but the manifestation of the will, the becoming visible, _the objectification of the will_. Upon this rests the perfect suitableness of the human and animal body to the human and animal will in general, resembling, though far surpassing, the correspondence between an instrument made for a purpose and the will of the maker, and on this account appearing as design, _i.e._, the teleological explanation of the body. The parts of the body must, therefore, completely correspond to the principal desires through which the will manifests itself; they must be the visible expression of these desires. Teeth, throat, and bowels are objectified hunger; the organs of generation are objectified sexual desire; the grasping hand, the hurrying feet, correspond to the more indirect desires of the will which they express. As the human form generally corresponds to the human will generally, so the individual bodily structure corresponds to the individually modified will, the character of the individual, and therefore it is throughout and in all its parts characteristic and full of expression. It is very remarkable that Parmenides already gave expression to this in the following verses, quoted by Aristotle (Metaph. iii. 5):—

Ὁς γαρ ἑκαστος εχει κρασιν μελεων πολυκαμπτων Τως νοος ανθρωποισι παρεστηκεν; το γαρ αυτο Εστιν, ὁπερ φρονεει, μελεων φυσις ανθρωποισι Και πασιν και παντι; το γαρ πλεον εστι νοημα.

(Ut enim cuique complexio membrorum flexibilium se habet, ita mens hominibus adest: idem namque est, quod sapit, membrorum natura hominibus, et omnibus et omni: quod enim plus est, intelligentia est.)(30)

§ 21. Whoever has now gained from all these expositions a knowledge _in abstracto_, and therefore clear and certain, of what every one knows directly _in concreto_, _i.e._, as feeling, a knowledge that his will is the real inner nature of his phenomenal being, which manifests itself to him as idea, both in his actions and in their permanent substratum, his body, and that his will is that which is most immediate in his consciousness, though it has not as such completely passed into the form of idea in which object and subject stand over against each other, but makes itself known to him in a direct manner, in which he does not quite clearly distinguish subject and object, yet is not known as a whole to the individual himself, but only in its particular acts,—whoever, I say, has with me gained this conviction will find that of itself it affords him the key to the knowledge of the inmost being of the whole of nature; for he now transfers it to all those phenomena which are not given to him, like his own phenomenal existence, both in direct and indirect knowledge, but only in the latter, thus merely one-sidedly as _idea_ alone. He will recognise this will of which we are speaking not only in those phenomenal existences which exactly resemble his own, in men and animals as their inmost nature, but the course of reflection will lead him to recognise the force which germinates and vegetates in the plant, and indeed the force through which the crystal is formed, that by which the magnet turns to the north pole, the force whose shock he experiences from the contact of two different kinds of metals, the force which appears in the elective affinities of matter as repulsion and attraction, decomposition and combination, and, lastly, even gravitation, which acts so powerfully throughout matter, draws the stone to the earth and the earth to the sun,—all these, I say, he will recognise as different only in their phenomenal existence, but in their inner nature as identical, as that which is directly known to him so intimately and so much better than anything else, and which in its most distinct manifestation is called _will_. It is this application of reflection alone that prevents us from remaining any longer at the phenomenon, and leads us to the _thing in itself_. Phenomenal existence is idea and nothing more. All idea, of whatever kind it may be, all _object_, is _phenomenal_ existence, but the _will_ alone is a _thing in itself_. As such, it is throughout not idea, but _toto genere_ different from it; it is that of which all idea, all object, is the phenomenal appearance, the visibility, the objectification. It is the inmost nature, the kernel, of every particular thing, and also of the whole. It appears in every blind force of nature and also in the preconsidered action of man; and the great difference between these two is merely in the degree of the manifestation, not in the nature of what manifests itself.

§ 22. Now, if we are to think as an object this thing-in-itself (we wish to retain the Kantian expression as a standing formula), which, as such, is never object, because all object is its mere manifestation, and therefore cannot be it itself, we must borrow for it the name and concept of an object, of something in some way objectively given, consequently of one of its own manifestations. But in order to serve as a clue for the understanding, this can be no other than the most complete of all its manifestations, _i.e._, the most distinct, the most developed, and directly enlightened by knowledge. Now this is the human will. It is, however, well to observe that here, at any rate, we only make use of a _denominatio a potiori_, through which, therefore, the concept of will receives a greater extension than it has hitherto had. Knowledge of the identical in different phenomena, and of difference in similar phenomena, is, as Plato so often remarks, a _sine qua non_ of philosophy. But hitherto it was not recognised that every kind of active and operating force in nature is essentially identical with will, and therefore the multifarious kinds of phenomena were not seen to be merely different species of the same genus, but were treated as heterogeneous. Consequently there could be no word to denote the concept of this genus. I therefore name the genus after its most important species, the direct knowledge of which lies nearer to us and guides us to the indirect knowledge of all other species. But whoever is incapable of carrying out the required extension of the concept will remain involved in a permanent misunderstanding. For by the word _will_ he understands only that species of it which has hitherto been exclusively denoted by it, the will which is guided by knowledge, and whose manifestation follows only upon motives, and indeed merely abstract motives, and thus takes place under the guidance of the reason. This, we have said, is only the most prominent example of the manifestation of will. We must now distinctly separate in thought the inmost essence of this manifestation which is known to us directly, and then transfer it to all the weaker, less distinct manifestations of the same nature, and thus we shall accomplish the desired extension of the concept of will. From another point of view I should be equally misunderstood by any one who should think that it is all the same in the end whether we denote this inner nature of all phenomena by the word _will_ or by any other. This would be the case if the thing-in-itself were something whose existence we merely _inferred_, and thus knew indirectly and only in the abstract. Then, indeed, we might call it what we pleased; the name would stand merely as the symbol of an unknown quantity. But the word _will_, which, like a magic spell, discloses to us the inmost being of everything in nature, is by no means an unknown quantity, something arrived at only by inference, but is fully and immediately comprehended, and is so familiar to us that we know and understand what will is far better than anything else whatever. The concept of will has hitherto commonly been subordinated to that of force, but I reverse the matter entirely, and desire that every force in nature should be thought as will. It must not be supposed that this is mere verbal quibbling or of no consequence; rather, it is of the greatest significance and importance. For at the foundation of the concept of force, as of all other concepts, there ultimately lies the knowledge in sense-perception of the objective world, that is to say, the phenomenon, the idea; and the concept is constructed out of this. It is an abstraction from the province in which cause and effect reign, _i.e._, from ideas of perception, and means just the causal nature of causes at the point at which this causal nature is no further etiologically explicable, but is the necessary presupposition of all etiological explanation. The concept will, on the other hand, is of all possible concepts the only one which has its source _not_ in the phenomenal, _not_ in the mere idea of perception, but comes from within, and proceeds from the most immediate consciousness of each of us, in which each of us knows his own individuality, according to its nature, immediately, apart from all form, even that of subject and object, and which at the same time is this individuality, for here the subject and the object of knowledge are one. If, therefore, we refer the concept of _force_ to that of _will_, we have in fact referred the less known to what is infinitely better known; indeed, to the one thing that is really immediately and fully known to us, and have very greatly extended our knowledge. If, on the contrary, we subsume the concept of will under that of force, as has hitherto always been done, we renounce the only immediate knowledge which we have of the inner nature of the world, for we allow it to disappear in a concept which is abstracted from the phenomenal, and with which we can therefore never go beyond the phenomenal.

§ 23. The _will_ as a thing in itself is quite different from its phenomenal appearance, and entirely free from all the forms of the phenomenal, into which it first passes when it manifests itself, and which therefore only concern its _objectivity_, and are foreign to the will itself. Even the most universal form of all idea, that of being object for a subject, does not concern it; still less the forms which are subordinate to this and which collectively have their common expression in the principle of sufficient reason, to which we know that time and space belong, and consequently multiplicity also, which exists and is possible only through these. In this last regard I shall call time and space the _principium individuationis_, borrowing an expression from the old schoolmen, and I beg to draw attention to this, once for all. For it is only through the medium of time and space that what is one and the same, both according to its nature and to its concept, yet appears as different, as a multiplicity of co-existent and successive phenomena. Thus time and space are the _principium individuationis_, the subject of so many subtleties and disputes among the schoolmen, which may be found collected in Suarez (Disp. 5, Sect. 3). According to what has been said, the will as a thing-in-itself lies outside the province of the principle of sufficient reason in all its forms, and is consequently completely groundless, although all its manifestations are entirely subordinated to the principle of sufficient reason. Further, it is free from all _multiplicity_, although its manifestations in time and space are innumerable. It is itself one, though not in the sense in which an object is one, for the unity of an object can only be known in opposition to a possible multiplicity; nor yet in the sense in which a concept is one, for the unity of a concept originates only in abstraction from a multiplicity; but it is one as that which lies outside time and space, the _principium individuationis_, _i.e._, the possibility of multiplicity. Only when all this has become quite clear to us through the subsequent examination of the phenomena and different manifestations of the will, shall we fully understand the meaning of the Kantian doctrine that time, space and causality do not belong to the thing-in-itself, but are only forms of knowing.

The uncaused nature of will has been actually recognised, where it manifests itself most distinctly, as the will of man, and this has been called free, independent. But on account of the uncaused nature of the will itself, the necessity to which its manifestation is everywhere subjected has been overlooked, and actions are treated as free, which they are not. For every individual action follows with strict necessity from the effect of the motive upon the character. All necessity is, as we have already said, the relation of the consequent to the reason, and nothing more. The principle of sufficient reason is the universal form of all phenomena, and man in his action must be subordinated to it like every other phenomenon. But because in self-consciousness the will is known directly and in itself, in this consciousness lies also the consciousness of freedom. The fact is, however, overlooked that the individual, the person, is not will as a thing-in-itself, but is a _phenomenon_ of will, is already determined as such, and has come under the form of the phenomenal, the principle of sufficient reason. Hence arises the strange fact that every one believes himself _a priori_ to be perfectly free, even in his individual actions, and thinks that at every moment he can commence another manner of life, which just means that he can become another person. But _a posteriori_, through experience, he finds to his astonishment that he is not free, but subjected to necessity; that in spite of all his resolutions and reflections he does not change his conduct, and that from the beginning of his life to the end of it, he must carry out the very character which he himself condemns, and as it were play the part he has undertaken to the end. I cannot pursue this subject further at present, for it belongs, as ethical, to another part of this work. In the meantime, I only wish to point out here that the _phenomenon_ of the will which in itself is uncaused, is yet as such subordinated to the law of necessity, that is, the principle of sufficient reason, so that in the necessity with which the phenomena of nature follow each other, we may find nothing to hinder us from recognising in them the manifestations of will.

Only those changes which have no other ground than a motive, _i.e._, an idea, have hitherto been regarded as manifestations of will. Therefore in nature a will has only been attributed to man, or at the most to animals; for knowledge, the idea, is of course, as I have said elsewhere, the true and exclusive characteristic of animal life. But that the will is also

## active where no knowledge guides it, we see at once in the instinct and

the mechanical skill of animals.(31) That they have ideas and knowledge is here not to the point, for the end towards which they strive as definitely as if it were a known motive, is yet entirely unknown to them. Therefore in such cases their action takes place without motive, is not guided by the idea, and shows us first and most distinctly how the will may be

## active entirely without knowledge. The bird of a year old has no idea of

the eggs for which it builds a nest; the young spider has no idea of the prey for which it spins a web; nor has the ant-lion any idea of the ants for which he digs a trench for the first time. The larva of the stag-beetle makes the hole in the wood, in which it is to await its metamorphosis, twice as big if it is going to be a male beetle as if it is going to be a female, so that if it is a male there may be room for the horns, of which, however, it has no idea. In such actions of these creatures the will is clearly operative as in their other actions, but it is in blind activity, which is indeed accompanied by knowledge but not guided by it. If now we have once gained insight into the fact, that idea as motive is not a necessary and essential condition of the activity of the will, we shall more easily recognise the activity of will where it is less apparent. For example, we shall see that the house of the snail is no more made by a will which is foreign to the snail itself, than the house which we build is produced through another will than our own; but we shall recognise in both houses the work of a will which objectifies itself in both the phenomena—a will which works in us according to motives, but in the snail still blindly as formative impulse directed outwards. In us also the same will is in many ways only blindly active: in all the functions of our body which are not guided by knowledge, in all its vital and vegetative processes, digestion, circulation, secretion, growth, reproduction. Not only the actions of the body, but the whole body itself is, as we have shown above, phenomenon of the will, objectified will, concrete will. All that goes on in it must therefore proceed through will, although here this will is not guided by knowledge, but acts blindly according to causes, which in this case are called _stimuli_.

I call a _cause_, in the narrowest sense of the word, that state of matter, which, while it introduces another state with necessity, yet suffers just as great a change itself as that which it causes; which is expressed in the rule, “action and reaction are equal.” Further, in the case of what is properly speaking a cause, the effect increases directly in proportion to the cause, and therefore also the reaction. So that, if once the mode of operation be known, the degree of the effect may be measured and calculated from the degree of the intensity of the cause; and conversely the degree of the intensity of the cause may be calculated from the degree of the effect. Such causes, properly so called, operate in all the phenomena of mechanics, chemistry, and so forth; in short, in all the changes of unorganised bodies. On the other hand, I call a _stimulus_, such a cause as sustains no reaction proportional to its effect, and the intensity of which does not vary directly in proportion to the intensity of its effect, so that the effect cannot be measured by it. On the contrary, a small increase of the stimulus may cause a very great increase of the effect, or conversely, it may eliminate the previous effect altogether, and so forth. All effects upon organised bodies as such are of this kind. All properly organic and vegetative changes of the animal body must therefore be referred to stimuli, not to mere causes. But the stimulus, like every cause and motive generally, never determines more than the point of time and space at which the manifestation of every force is to take place, and does not determine the inner nature of the force itself which is manifested. This inner nature we know, from our previous investigation, is will, to which therefore we ascribe both the unconscious and the conscious changes of the body. The stimulus holds the mean, forms the transition between the motive, which is causality accompanied throughout by knowledge, and the cause in the narrowest sense. In

## particular cases it is sometimes nearer a motive, sometimes nearer a

cause, but yet it can always be distinguished from both. Thus, for example, the rising of the sap in a plant follows upon stimuli, and cannot be explained from mere causes, according to the laws of hydraulics or capillary attraction; yet it is certainly assisted by these, and altogether approaches very near to a purely causal change. On the other hand, the movements of the _Hedysarum gyrans_ and the _Mimosa pudica_, although still following upon mere stimuli, are yet very like movements which follow upon motives, and seem almost to wish to make the transition. The contraction of the pupils of the eyes as the light is increased is due to stimuli, but it passes into movement which is due to motive; for it takes place, because too strong lights would affect the retina painfully, and to avoid this we contract the pupils. The occasion of an erection is a motive, because it is an idea, yet it operates with the necessity of a stimulus, _i.e._, it cannot be resisted, but we must put the idea away in order to make it cease to affect us. This is also the case with disgusting things, which excite the desire to vomit. Thus we have treated the instinct of animals as an actual link, of quite a distinct kind, between movement following upon stimuli, and action following upon a known motive. Now we might be asked to regard breathing as another link of this kind. It has been disputed whether it belongs to the voluntary or the involuntary movements, that is to say, whether it follows upon motive or stimulus, and perhaps it may be explained as something which is between the two. Marshall Hall (“On the Diseases of the Nervous System,” § 293 sq.) explains it as a mixed function, for it is partly under the influence of the cerebral (voluntary), and partly under that of the spinal (non-voluntary) nerves. However, we are finally obliged to number it with the expressions of will which result from motives. For other motives, _i.e._, mere ideas, can determine the will to check it or accelerate it, and, as is the case with every other voluntary action, it seems to us that we could give up breathing altogether and voluntarily suffocate. And in fact we could do so if any other motive influenced the will sufficiently strongly to overcome the pressing desire for air. According to some accounts Diogenes actually put an end to his life in this way (Diog. Laert. VI. 76). Certain negroes also are said to have done this (F. B. Osiander “On Suicide” [1813] pp. 170-180). If this be true, it affords us a good example of the influence of abstract motives, _i.e._, of the victory of distinctively rational over merely animal will. For, that breathing is at least partially conditioned by cerebral activity is shown by the fact that the primary cause of death from prussic acid is that it paralyses the brain, and so, indirectly, restricts the breathing; but if the breathing be artificially maintained till the stupefaction of the brain has passed away, death will not ensue. We may also observe in passing that breathing affords us the most obvious example of the fact that motives act with just as much necessity as stimuli, or as causes in the narrowest sense of the word, and their operation can only be neutralised by antagonistic motives, as action is neutralised by re-action. For, in the case of breathing, the illusion that we can stop when we like is much weaker than in the case of other movements which follow upon motives; because in breathing the motive is very powerful, very near to us, and its satisfaction is very easy, for the muscles which accomplish it are never tired, nothing, as a rule, obstructs it, and the whole process is supported by the most inveterate habit of the individual. And yet all motives act with the same necessity. The knowledge that necessity is common to movements following upon motives, and those following upon stimuli, makes it easier for us to understand that that also which takes place in our bodily organism in accordance with stimuli and in obedience to law, is yet, according to its inner nature—will, which in all its manifestations, though never in itself, is subordinated to the principle of sufficient reason, that is, to necessity.(32) Accordingly, we shall not rest contented with recognising that animals, both in their

## actions and also in their whole existence, bodily structure and

organisation, are manifestations of will; but we shall extend to plants also this immediate knowledge of the essential nature of things which is given to us alone. Now all the movements of plants follow upon stimuli; for the absence of knowledge, and the movement following upon motives which is conditioned by knowledge, constitutes the only essential difference between animals and plants. Therefore, what appears for the idea as plant life, as mere vegetation, as blindly impelling force, we shall claim, according to its inner nature, for will, and recognise it as just that which constitutes the basis of our own phenomenal being, as it expresses itself in our actions, and also in the whole existence of our body itself.

It only remains for us to take the final step, the extension of our way of looking at things to all those forces which act in nature in accordance with universal, unchangeable laws, in conformity with which the movements of all those bodies take place, which are wholly without organs, and have therefore no susceptibility for stimuli, and have no knowledge, which is the necessary condition of motives. Thus we must also apply the key to the understanding of the inner nature of things, which the immediate knowledge of our own existence alone can give us, to those phenomena of the unorganised world which are most remote from us. And if we consider them attentively, if we observe the strong and unceasing impulse with which the waters hurry to the ocean, the persistency with which the magnet turns ever to the north pole, the readiness with which iron flies to the magnet, the eagerness with which the electric poles seek to be re-united, and which, just like human desire, is increased by obstacles; if we see the crystal quickly and suddenly take form with such wonderful regularity of construction, which is clearly only a perfectly definite and accurately determined impulse in different directions, seized and retained by crystallisation; if we observe the choice with which bodies repel and attract each other, combine and separate, when they are set free in a fluid state, and emancipated from the bonds of rigidness; lastly, if we feel directly how a burden which hampers our body by its gravitation towards the earth, unceasingly presses and strains upon it in pursuit of its one tendency; if we observe all this, I say, it will require no great effort of the imagination to recognise, even at so great a distance, our own nature. That which in us pursues its ends by the light of knowledge; but here, in the weakest of its manifestations, only strives blindly and dumbly in a one-sided and unchangeable manner, must yet in both cases come under the name of will, as it is everywhere one and the same—just as the first dim light of dawn must share the name of sunlight with the rays of the full mid-day. For the name _will_ denotes that which is the inner nature of everything in the world, and the one kernel of every phenomenon.

Yet the remoteness, and indeed the appearance of absolute difference between the phenomena of unorganised nature and the will which we know as the inner reality of our own being, arises chiefly from the contrast between the completely determined conformity to law of the one species of phenomena, and the apparently unfettered freedom of the other. For in man, individuality makes itself powerfully felt. Every one has a character of his own; and therefore the same motive has not the same influence over all, and a thousand circumstances which exist in the wide sphere of the knowledge of the individual, but are unknown to others, modify its effect. Therefore action cannot be predetermined from the motive alone, for the other factor is wanting, the accurate acquaintance with the individual character, and with the knowledge which accompanies it. On the other hand, the phenomena of the forces of nature illustrate the opposite extreme. They act according to universal laws, without variation, without individuality in accordance with openly manifest circumstances, subject to the most exact predetermination; and the same force of nature appears in its million phenomena in precisely the same way. In order to explain this point and prove the identity of the _one_ indivisible will in all its different phenomena, in the weakest as in the strongest, we must first of all consider the relation of the will as thing-in-itself to its phenomena, that is, the relation of the world as will to the world as idea; for this will open to us the best way to a more thorough investigation of the whole subject we are considering in this second book.(33)

§ 24. We have learnt from the great Kant that time, space, and causality, with their entire constitution, and the possibility of all their forms, are present in our consciousness quite independently of the objects which appear in them, and which constitute their content; or, in other words, they can be arrived at just as well if we start from the subject as if we start from the object. Therefore, with equal accuracy, we may call them either forms of intuition or perception of the subject, or qualities of the object _as object_ (with Kant, phenomenon), _i.e._, _idea_. We may also regard these forms as the irreducible boundary between object and subject. All objects must therefore exist in them, yet the subject, independently of the phenomenal object, possesses and surveys them completely. But if the objects appearing in these forms are not to be empty phantoms, but are to have a meaning, they must refer to something, must be the expression of something which is not, like themselves, object, idea, a merely relative existence for a subject, but which exists without such dependence upon something which stands over against it as a condition of its being, and independent of the forms of such a thing, _i.e._, _is not idea_, but a _thing-in-itself_. Consequently it may at least be asked: Are these ideas, these objects, something more than or apart from the fact that they are ideas, objects of the subject? And what would they be in this sense? What is that other side of them which is _toto genere_ different from idea? What is the thing-in-itself? _The will_, we have answered, but for the present I set that answer aside.

Whatever the thing-in-itself may be, Kant is right in his conclusion that time, space, and causality (which we afterwards found to be forms of the principle of sufficient reason, the general expression of the forms of the phenomenon) are not its properties, but come to it only after, and so far as, it has become idea. That is, they belong only to its phenomenal existence, not to itself. For since the subject fully understands and constructs them out of itself, independently of all object, they must be dependent upon _existence as idea_ as such, not upon that which becomes idea. They must be the form of the idea as such; but not qualities of that which has assumed this form. They must be already given with the mere antithesis of subject and object (not as concepts but as facts), and consequently they must be only the more exact determination of the form of knowledge in general, whose most universal determination is that antithesis itself. Now, that in the phenomenon, in the object, which is in its turn conditioned by time, space and causality, inasmuch as it can only become idea by means of them, namely _multiplicity_, through co-existence and succession, _change_ and _permanence_ through the law of causality, _matter_ which can only become idea under the presupposition of causality, and lastly, all that becomes idea only by means of these,—all this, I say, as a whole, does not in reality belong to that which appears, to that which has passed into the form of idea, but belongs merely to this form itself. And conversely, that in the phenomenon which is not conditioned through time, space and causality, and which cannot be referred to them, nor explained in accordance with them, is precisely that in which the thing manifested, the thing-in-itself, directly reveals itself. It follows from this that the most complete capacity for being known, that is to say, the greatest clearness, distinctness, and susceptibility of exhaustive explanation, will necessarily belong to that which pertains to knowledge _as such_, and thus to the _form_ of knowledge; but not to that which in itself is not idea, not object, but which has become knowledge only through entering these forms; in other words, has become idea, object. Thus only that which depends entirely upon being an object of knowledge, upon existing as idea in general and _as such_ (not upon that which _becomes_ known, and has only _become_ idea), which therefore belongs without distinction to everything that is known, and which, on that account, is found just as well if we start from the subject as if we start from the object,—this alone can afford us without reserve a sufficient, exhaustive knowledge, a knowledge which is clear to the very foundation. But this consists of nothing but those forms of all phenomena of which we are conscious _a priori_, and which may be generally expressed as the principle of sufficient reason. Now, the forms of this principle which occur in knowledge of perception (with which alone we are here concerned) are time, space, and causality. The whole of pure mathematics and pure natural science _a priori_ is based entirely upon these. Therefore it is only in these sciences that knowledge finds no obscurity, does not rest upon what is incomprehensible (groundless, _i.e._, will), upon what cannot be further deduced. It is on this account that Kant wanted, as we have said, to apply the name science specially and even exclusively to these branches of knowledge together with logic. But, on the other hand, these branches of knowledge show us nothing more than mere connections, relations of one idea to another, form devoid of all content. All content which they receive, every phenomenon which fills these forms, contains something which is no longer completely knowable in its whole nature, something which can no longer be entirely explained through something else, something then which is groundless, through which consequently the knowledge loses its evidence and ceases to be completely lucid. This that withholds itself from investigation, however, is the thing-in-itself, is that which is essentially not idea, not object of knowledge, but has only become knowable by entering that form. The form is originally foreign to it, and the thing-in-itself can never become entirely one with it, can never be referred to mere form, and, since this form is the principle of sufficient reason, can never be completely explained. If therefore all mathematics affords us an exhaustive knowledge of that which in the phenomena is quantity, position, number, in a word, spatial and temporal relations; if all etiology gives us a complete account of the regular conditions under which phenomena, with all their determinations, appear in time and space, but, with it all, teaches us nothing more than why in each case this particular phenomenon must appear just at this time here, and at this place now; it is clear that with their assistance we can never penetrate to the inner nature of things. There always remains something which no explanation can venture to attack, but which it always presupposes; the forces of nature, the definite mode of operation of things, the quality and character of every phenomenon, that which is without ground, that which does not depend upon the form of the phenomenal, the principle of sufficient reason, but is something to which this form in itself is foreign, something which has yet entered this form, and now appears according to its law, a law, however, which only determines the appearance, not that which appears, only the how, not the what, only the form, not the content. Mechanics, physics, and chemistry teach the rules and laws according to which the forces of impenetrability, gravitation, rigidity, fluidity, cohesion, elasticity, heat, light, affinity, magnetism, electricity, &c., operate; that is to say, the law, the rule which these forces observe whenever they enter time and space. But do what we will, the forces themselves remain _qualitates occultæ_. For it is just the thing-in-itself, which, because it is manifested, exhibits these phenomena, which are entirely different from itself. In its manifestation, indeed, it is completely subordinated to the principle of sufficient reason as the form of the idea, but it can never itself be referred to this form, and therefore cannot be fully explained etiologically, can never be completely fathomed. It is certainly perfectly comprehensible so far as it has assumed that form, that is, so far as it is phenomenon, but its inner nature is not in the least explained by the fact that it can thus be comprehended. Therefore the more necessity any knowledge carries with it, the more there is in it of that which cannot be otherwise thought or presented in perception—as, for example, space-relations—the clearer and more sufficing then it is, the less pure objective content it has, or the less reality, properly so called, is given in it. And conversely, the more there is in it which must be conceived as mere chance, and the more it impresses us as given merely empirically, the more proper objectivity and true reality is there in such knowledge, and at the same time, the more that is inexplicable, that is, that cannot be deduced from anything else.

It is true that at all times an etiology, unmindful of its real aim, has striven to reduce all organised life to chemism or electricity; all chemism, that is to say quality, again to mechanism (action determined by the shape of the atom), this again sometimes to the object of phoronomy, _i.e._, the combination of time and space, which makes motion possible, sometimes to the object of mere geometry, _i.e._, position in space (much in the same way as we rightly deduce the diminution of an effect from the square of the distance, and the theory of the lever in a purely geometrical manner): geometry may finally be reduced to arithmetic, which, on account of its one dimension, is of all the forms of the principle of sufficient reason, the most intelligible, comprehensible, and completely susceptible of investigation. As instances of the method generally indicated here, we may refer to the atoms of Democritus, the vortex of Descartes, the mechanical physics of Lesage, which towards the end of last century tried to explain both chemical affinities and gravitation mechanically by impact and pressure, as may be seen in detail in “_Lucrèce Neutonien_;” Reil’s form and combination as the cause of animal life, also tends in this direction. Finally, the crude materialism which even now in the middle of the nineteenth century has been served up again under the ignorant delusion that it is original, belongs distinctly to this class. It stupidly denies vital force, and first of all tries to explain the phenomena of life from physical and chemical forces, and those again from the mechanical effects of the matter, position, form, and motion of imagined atoms, and thus seeks to reduce all the forces of nature to

## action and reaction as its thing-in-itself. According to this teaching,

light is the mechanical vibration or undulation of an imaginary ether, postulated for this end. This ether, if it reaches the eye, beats rapidly upon the retina, and gives us the knowledge of colour. Thus, for example, four hundred and eighty-three billion beats in a second give red, and seven hundred and twenty-seven billion beats in a second give violet. Upon this theory, persons who are colour-blind must be those who are unable to count the beats, must they not? Such crass, mechanical, clumsy, and certainly knotty theories, which remind one of Democritus, are quite worthy of those who, fifty years after the appearance of Goethe’s doctrine of colour, still believe in Newton’s homogeneous light, and are not ashamed to say so. They will find that what is overlooked in the child (Democritus) will not be forgiven to the man. They might indeed, some day, come to an ignominious end; but then every one would slink away and pretend that he never had anything to do with them. We shall soon have to speak again of this false reduction of the forces of nature to each other; so much for the present. Supposing this theory were possible, all would certainly be explained and established and finally reduced to an arithmetical problem, which would then be the holiest thing in the temple of wisdom, to which the principle of sufficient reason would at last have happily conducted us. But all content of the phenomenon would have disappeared, and the mere form would remain. The “what appears” would be referred to the “how it appears,” and this “how” would be what is _a priori_ knowable, therefore entirely dependent on the subject, therefore only for the subject, therefore, lastly, mere phantom, idea and form of idea, through and through: no thing-in-itself could be demanded. Supposing, then, that this were possible, the whole world would be derived from the subject, and in fact, that would be accomplished which Fichte wanted to _seem_ to accomplish by his empty bombast. But it is not possible: phantasies, sophisms, castles in the air, have been constructed in this way, but science never. The many and multifarious phenomena in nature have been successfully referred to particular original forces, and as often as this has been done, a real advance has been made. Several forces and qualities, which were at first regarded as different, have been derived from each other, and thus their number has been curtailed. (For example, magnetism from electricity.) Etiology will have reached its goal when it has recognised and exhibited as such all the original forces of nature, and established their mode of operation, _i.e._, the law according to which, under the guidance of causality, their phenomena appear in time and space, and determine their position with regard to each other. But certain original forces will always remain over; there will always remain as an insoluble residuum a content of phenomena which cannot be referred to their form, and thus cannot be explained from something else in accordance with the principle of sufficient reason. For in everything in nature there is something of which no ground can ever be assigned, of which no explanation is possible, and no ulterior cause is to be sought. This is the specific nature of its action, _i.e._, the nature of its existence, its being. Of each particular effect of the thing a cause may be certainly indicated, from which it follows that it must act just at this time and in this place; but no cause can ever be found from which it follows that a thing acts in general, and precisely in the way it does. If it has no other qualities, if it is merely a mote in a sunbeam, it yet exhibits this unfathomable something, at least as weight and impenetrability. But this, I say, is to the mote what his will is to a man; and, like the human will, it is, according to its inner nature, not subject to explanation; nay, more—it is in itself identical with this will. It is true that a motive may be given for every manifestation of will, for every act of will at a particular time and in a particular place, upon which it must necessarily follow, under the presupposition of the character of the man. But no reason can ever be given that the man has this character; that he wills at all; that, of several motives, just this one and no other, or indeed that any motive at all, moves his will. That which in the case of man is the unfathomable character which is presupposed in every explanation of his actions from motives is, in the case of every unorganised body, its definitive quality—the mode of its

## action, the manifestations of which are occasioned by impressions from

without, while it itself, on the contrary, is determined by nothing outside itself, and thus is also inexplicable. Its particular manifestations, through which alone it becomes visible, are subordinated to the principle of sufficient reason; it itself is groundless. This was in substance rightly understood by the schoolmen, who called it _forma substantialis_. (Cf. Suarez, Disput. Metaph., disp. xv. sect. 1.)

It is a greater and a commoner error that the phenomena which we best understand are those which are of most frequent occurrence, and which are most universal and simple; for, on the contrary, these are just the phenomena that we are most accustomed to see about us, and to be ignorant of. It is just as inexplicable to us that a stone should fall to the earth as that an animal should move itself. It has been supposed, as we have remarked above, that, starting from the most universal forces of nature (gravitation, cohesion, impenetrability), it was possible to explain from them the rarer forces, which only operate under a combination of circumstances (for example, chemical quality, electricity, magnetism), and, lastly, from these to understand the organism and the life of animals, and even the nature of human knowing and willing. Men resigned themselves without a word to starting from mere _qualitates occultæ_, the elucidation of which was entirely given up, for they intended to build upon them, not to investigate them. Such an intention cannot, as we have already said, be carried out. But apart from this, such structures would always stand in the air. What is the use of explanations which ultimately refer us to something which is quite as unknown as the problem with which we started? Do we in the end understand more of the inner nature of these universal natural forces than of the inner nature of an animal? Is not the one as much a sealed book to us as the other? Unfathomable because it is without ground, because it is the content, that which the phenomenon is, and which can never be referred to the form, to the how, to the principle of sufficient reason. But we, who have in view not etiology but philosophy, that is, not relative but unconditioned knowledge of the real nature of the world, take the opposite course, and start from that which is immediately and most completely known to us, and fully and entirely trusted by us—that which lies nearest to us, in order to understand that which is known to us only at a distance, one-sidedly and indirectly. From the most powerful, most significant, and most distinct phenomenon we seek to arrive at an understanding of those that are less complete and weaker. With the exception of my own body, all things are known to me only on _one_ side, that of the idea. Their inner nature remains hidden from me and a profound secret, even if I know all the causes from which their changes follow. Only by comparison with that which goes on in me if my body performs an action when I am influenced by a motive—only by comparison, I say, with what is the inner nature of my own changes determined by external reasons, can I obtain insight into the way in which these lifeless bodies change under the influence of causes, and so understand what is their inner nature. For the knowledge of the causes of the manifestation of this inner nature affords me merely the rule of its appearance in time and space, and nothing more. I can make this comparison because my body is the only object of which I know not merely the _one_ side, that of the idea, but also the other side which is called will. Thus, instead of believing that I would better understand my own organisation, and then my own knowing and willing, and my movements following upon motives, if I could only refer them to movements due to electrical, chemical, and mechanical causes, I must, seeing that I seek philosophy and not etiology, learn to understand from my own movements following upon motives the inner nature of the simplest and commonest movements of an unorganised body which I see following upon causes. I must recognise the inscrutable forces which manifest themselves in all natural bodies as identical in kind with that which in me is the will, and as differing from it only in degree. That is to say, the fourth class of ideas given in the Essay on the Principle of Sufficient Reason must be the key to the knowledge of the inner nature of the first class, and by means of the law of motivation I must come to understand the inner meaning of the law of causation.

Spinoza (Epist. 62) says that if a stone which has been projected through the air had consciousness, it would believe that it was moving of its own will. I add to this only that the stone would be right. The impulse given it is for the stone what the motive is for me, and what in the case of the stone appears as cohesion, gravitation, rigidity, is in its inner nature the same as that which I recognise in myself as will, and what the stone also, if knowledge were given to it, would recognise as will. In the passage referred to, Spinoza had in view the necessity with which the stone flies, and he rightly desires to transfer this necessity to that of the particular act of will of a person. I, on the other hand, consider the inner being, which alone imparts meaning and validity to all real necessity (_i.e._, effect following upon a cause) as its presupposition. In the case of men this is called character; in the case of a stone it is called quality, but it is the same in both. When it is immediately known it is called will. In the stone it has the weakest, and in man the strongest degree of visibility, of objectivity. St. Augustine recognises, with a true instinct, this identity of the tendencies of all things with our own willing, and I cannot refrain from quoting his naïve account of the matter:—“_Si pecora essemus, carnalem vitam et quod secundum sensum ejusdem est amaremus, idque esset sufficiens bonum nostrum, et secundum hoc si esset nobis bene, nihil aliud quæreremus. Item, si arbores essemus, nihil quidem sentientes motu amare possemus: verumtamen id quasi appetere videremur, quo feracius essemus, uberiusque fructuosæ. Si essemus lapides, aut fluctus, aut ventus, aut flamma, vel quid ejusmodi, sine ullo quidem sensu atque vita, non tamen nobis deesset quasi quidam nostrorum locorum atque ordinis appetitus. Nam velut amores corporum momenta sunt ponderum, sive deorsum gravitate, sive sursum levitate nitantur: ita enim corpus pondere, sicut animus amore fertur quocunque fertur_” (De Civ. Dei, xi. 28).

It ought further to be mentioned that Euler saw that the inner nature of gravitation must ultimately be referred to an “inclination and desire” (thus will) peculiar to material bodies (in the 68th letter to the Princess). Indeed, it is just this that makes him averse to the conception of gravitation as it existed for Newton, and he is inclined to try a modification of it in accordance with the earlier Cartesian theory, and so to derive gravitation from the impact of an ether upon the bodies, as being “more rational and more suitable for persons who like clear and intelligible principles.” He wishes to banish attraction from physics as a _qualitas occulta_. This is only in keeping with the dead view of nature which prevailed at Euler’s time as the correlative of the immaterial soul. It is only worth noticing because of its bearing upon the fundamental truth established by me, which even at that time this fine intellect saw glimmering in the distance. He hastened to turn in time, and then, in his anxiety at seeing all the prevalent fundamental views endangered, he sought safety in the old and already exploded absurdities.

We know that _multiplicity_ in general is necessarily conditioned by space and time, and is only thinkable in them. In this respect they are called the _principium individuationis_. But we have found that space and time are forms of the principle of sufficient reason. In this principle all our knowledge _a priori_ is expressed, but, as we showed above, this _a priori_ knowledge, as such, only applies to the knowableness of things, not to the things themselves, _i.e._, it is only our form of knowledge, it is not a property of the thing-in-itself. The thing-in-itself is, as such, free from all forms of knowledge, even the most universal, that of being an object for the subject. In other words, the thing-in-itself is something altogether different from the idea. If, now, this thing-in-itself is _the will_, as I believe I have fully and convincingly proved it to be, then, regarded as such and apart from its manifestation, it lies outside time and space, and therefore knows no multiplicity, and is consequently _one_. Yet, as I have said, it is not one in the sense in which an individual or a concept is one, but as something to which the condition of the possibility of multiplicity, the _principium individuationis_, is foreign. The multiplicity of things in space and time, which collectively constitute the objectification of will, does not affect the will itself, which remains indivisible notwithstanding it. It is not the case that, in some way or other, a smaller part of will is in the stone and a larger part in the man, for the relation of part and whole belongs exclusively to space, and has no longer any meaning when we go beyond this form of intuition or perception. The more and the less have application only to the phenomenon of will, that is, its visibility, its objectification. Of this there is a higher grade in the plant than in the stone; in the animal a higher grade than in the plant: indeed, the passage of will into visibility, its objectification, has grades as innumerable as exist between the dimmest twilight and the brightest sunshine, the loudest sound and the faintest echo. We shall return later to the consideration of these grades of visibility which belong to the objectification of the will, to the reflection of its nature. But as the grades of its objectification do not directly concern the will itself, still less is it concerned by the multiplicity of the phenomena of these different grades, _i.e._, the multitude of individuals of each form, or the particular manifestations of each force. For this multiplicity is directly conditioned by time and space, into which the will itself never enters. The will reveals itself as completely and as much in _one_ oak as in millions. Their number and multiplication in space and time has no meaning with regard to it, but only with regard to the multiplicity of individuals who know in space and time, and who are themselves multiplied and dispersed in these. The multiplicity of these individuals itself belongs not to the will, but only to its manifestation. We may therefore say that if, _per impossibile_, a single real existence, even the most insignificant, were to be entirely annihilated, the whole world would necessarily perish with it. The great mystic Angelus Silesius feels this when he says—

“I know God cannot live an instant without me, He must give up the ghost if I should cease to be.”

Men have tried in various ways to bring the immeasurable greatness of the material universe nearer to the comprehension of us all, and then they have seized the opportunity to make edifying remarks. They have referred perhaps to the relative smallness of the earth, and indeed of man; or, on the contrary, they have pointed out the greatness of the mind of this man who is so insignificant—the mind that can solve, comprehend, and even measure the greatness of the universe, and so forth. Now, all this is very well, but to me, when I consider the vastness of the world, the most important point is this, that the thing-in-itself, whose manifestation is the world—whatever else it may be—cannot have its true self spread out and dispersed after this fashion in boundless space, but that this endless extension belongs only to its manifestation. The thing-in-itself, on the contrary, is present entire and undivided in every object of nature and in every living being. Therefore we lose nothing by standing still beside any single individual thing, and true wisdom is not to be gained by measuring out the boundless world, or, what would be more to the purpose, by actually traversing endless space. It is rather to be attained by the thorough investigation of any individual thing, for thus we seek to arrive at a full knowledge and understanding of its true and peculiar nature.

The subject which will therefore be fully considered in the next book, and which has, doubtless, already presented itself to the mind of every student of Plato, is, that these different grades of the objectification of will which are manifested in innumerable individuals, and exist as their unattained types or as the eternal forms of things, not entering themselves into time and space, which are the medium of individual things, but remaining fixed, subject to no change, always being, never becoming, while the particular things arise and pass away, always become and never are,—that these _grades of the objectification of will_ are, I say, simply _Plato’s Ideas_. I make this passing reference to the matter here in order that I may be able in future to use the word _Idea_ in this sense. In my writings, therefore, the word is always to be understood in its true and original meaning given to it by Plato, and has absolutely no reference to those abstract productions of dogmatising scholastic reason, which Kant has inaptly and illegitimately used this word to denote, though Plato had already appropriated and used it most fitly. By Idea, then, I understand every definite and fixed grade of the objectification of will, so far as it is thing-in-itself, and therefore has no multiplicity. These grades are related to individual things as their eternal forms or prototypes. The shortest and most concise statement of this famous Platonic doctrine is given us by Diogenes Laertes (iii. 12): “ὁ Πλατων φησι, εν τῃ φυσει τας ιδεας ἑσταναι, καθαπερ παραδειγματα, τα δ᾽ αλλα ταυταις εοικεναι, τουτων ὁμοιωματα καθεστωτα”—(“_Plato ideas in natura velut exemplaria dixit subsistere; cetera his esse similia, ad istarum similitudinem consistentia_”). Of Kant’s misuse of the word I take no further notice; what it is needful to say about it will be found in the Appendix.

§ 26. The lowest grades of the objectification of will are to be found in those most universal forces of nature which partly appear in all matter without exception, as gravity and impenetrability, and partly have shared the given matter among them, so that certain of them reign in one species of matter and others in another species, constituting its specific difference, as rigidity, fluidity, elasticity, electricity, magnetism, chemical properties and qualities of every kind. They are in themselves immediate manifestations of will, just as much as human action; and as such they are groundless, like human character. Only their particular manifestations are subordinated to the principle of sufficient reason, like the particular actions of men. They themselves, on the other hand, can never be called either effect or cause, but are the prior and presupposed conditions of all causes and effects through which their real nature unfolds and reveals itself. It is therefore senseless to demand a cause of gravity or electricity, for they are original forces. Their expressions, indeed, take place in accordance with the law of cause and effect, so that every one of their particular manifestations has a cause, which is itself again just a similar particular manifestation which determines that this force must express itself here, must appear in space and time; but the force itself is by no means the effect of a cause, nor the cause of an effect. It is therefore a mistake to say “gravity is the cause of a stone falling;” for the cause in this case is rather the nearness of the earth, because it attracts the stone. Take the earth away and the stone will not fall, although gravity remains. The force itself lies quite outside the chain of causes and effects, which presupposes time, because it only has meaning in relation to it; but the force lies outside time. The individual change always has for its cause another change just as individual as itself, and not the force of which it is the expression. For that which always gives its efficiency to a cause, however many times it may appear, is a force of nature. As such, it is groundless, _i.e._, it lies outside the chain of causes and outside the province of the principle of sufficient reason in general, and is philosophically known as the immediate objectivity of will, which is the “in-itself” of the whole of nature; but in etiology, which in this reference is physics, it is set down as an original force, _i.e._, a _qualitas occulta_.

In the higher grades of the objectivity of will we see individuality occupy a prominent position, especially in the case of man, where it appears as the great difference of individual characters, _i.e._, as complete personality, outwardly expressed in strongly marked individual physiognomy, which influences the whole bodily form. None of the brutes have this individuality in anything like so high a degree, though the higher species of them have a trace of it; but the character of the species completely predominates over it, and therefore they have little individual physiognomy. The farther down we go, the more completely is every trace of the individual character lost in the common character of the species, and the physiognomy of the species alone remains. We know the physiological character of the species, and from that we know exactly what is to be expected from the individual; while, on the contrary, in the human species every individual has to be studied and fathomed for himself, which, if we wish to forecast his action with some degree of certainty, is, on account of the possibility of concealment that first appears with reason, a matter of the greatest difficulty. It is probably connected with this difference of the human species from all others, that the folds and convolutions of the brain, which are entirely wanting in birds, and very weakly marked in rodents, are even in the case of the higher animals far more symmetrical on both sides, and more constantly the same in each individual, than in the case of human beings.(34) It is further to be regarded as a phenomenon of this peculiar individual character which distinguishes men from all the lower animals, that in the case of the brutes the sexual instinct seeks its satisfaction without observable choice of objects, while in the case of man this choice is, in a purely instinctive manner and independent of all reflection, carried so far that it rises into a powerful passion. While then every man is to be regarded as a specially determined and characterised phenomenon of will, and indeed to a certain extent as a special Idea, in the case of the brutes this individual character as a whole is wanting, because only the species has a special significance. And the farther we go from man, the fainter becomes the trace of this individual character, so that plants have no individual qualities left, except such as may be fully explained from the favourable or unfavourable external influences of soil, climate, and other accidents. Finally, in the inorganic kingdom of nature all individuality disappears. The crystal alone is to be regarded as to a certain extent individual. It is a unity of the tendency in definite directions, fixed by crystallisation, which makes the trace of this tendency permanent. It is at the same time a cumulative repetition of its primitive form, bound into unity by an idea, just as the tree is an aggregate of the single germinating fibre which shows itself in every rib of the leaves, in every leaf, in every branch; which repeats itself, and to some extent makes each of these appear as a separate growth, nourishing itself from the greater as a parasite, so that the tree, resembling the crystal, is a systematic aggregate of small plants, although only the whole is the complete expression of an individual Idea, _i.e._, of this particular grade of the objectification of will. But the individuals of the same species of crystal can have no other difference than such as is produced by external accidents; indeed we can make at pleasure large or small crystals of every species. The individual, however, as such, that is, with traces of an individual character, does not exist further in unorganised nature. All its phenomena are expressions of general forces of nature, _i.e._, of those grades of the objectification of will which do not objectify themselves (as is the case in organised nature), by means of the difference of the individualities which collectively express the whole of the Idea, but show themselves only in the species, and as a whole, without any variation in each particular example of it. Time, space, multiplicity, and existence conditioned by causes, do not belong to the will or to the Idea (the grade of the objectification of will), but only to their

## particular phenomena. Therefore such a force of nature as, for example,

gravity or electricity, must show itself as such in precisely the same way in all its million phenomena, and only external circumstances can modify these. This unity of its being in all its phenomena, this unchangeable constancy of the appearance of these, whenever, under the guidance of causality, the necessary conditions are present, is called a _law of nature_. If such a law is once learned from experience, then the phenomenon of that force of nature, the character of which is expressed and laid down in it, may be accurately forecast and counted upon. But it is just this conformity to law of the phenomena of the lower grades of the objectification of will which gives them such a different aspect from the phenomena of the same will in the higher, _i.e._, the more distinct, grades of its objectification, in animals, and in men and their actions, where the stronger or weaker influence of the individual character and the susceptibility to motives which often remain hidden from the spectator, because they lie in knowledge, has had the result that the identity of the inner nature of the two kinds of phenomena has hitherto been entirely overlooked.

If we start from the knowledge of the particular, and not from that of the Idea, there is something astonishing, and sometimes even terrible, in the absolute uniformity of the laws of nature. It might astonish us that nature never once forgets her laws; that if, for example, it has once been according to a law of nature that where certain materials are brought together under given conditions, a chemical combination will take place, or gas will be evolved, or they will go on fire; if these conditions are fulfilled, whether by our interposition or entirely by chance (and in this case the accuracy is the more astonishing because unexpected), to-day just as well as a thousand years ago, the determined phenomenon will take place at once and without delay. We are most vividly impressed with the marvellousness of this fact in the case of rare phenomena, which only occur under very complex circumstances, but which we are previously informed will take place if these conditions are fulfilled. For example, when we are told that if certain metals, when arranged alternately in fluid with which an acid has been mixed, are brought into contact, silver leaf brought between the extremities of this combination will suddenly be consumed in a green flame; or that under certain conditions the hard diamond turns into carbonic acid. It is the ghostly omnipresence of natural forces that astonishes us in such cases, and we remark here what in the case of phenomena which happen daily no longer strikes us, how the connection between cause and effect is really as mysterious as that which is imagined between a magic formula and a spirit that must appear when invoked by it. On the other hand, if we have attained to the philosophical knowledge that a force of nature is a definite grade of the objectification of will, that is to say, a definite grade of that which we recognise as our own inmost nature, and that this will, in itself, and distinguished from its phenomena and their forms, lies outside time and space, and that, therefore, the multiplicity, which is conditioned by time and space, does not belong to it, nor directly to the grade of its objectification, _i.e._, the Idea, but only to the phenomena of the Idea; and if we remember that the law of causality has significance only in relation to time and space, inasmuch as it determines the position of the multitude of phenomena of the different Ideas in which the will reveals itself, governing the order in which they must appear; if, I say, in this knowledge the inner meaning of the great doctrine of Kant has been fully grasped, the doctrine that time, space, and causality do not belong to the thing-in-itself, but merely to the phenomenon, that they are only the forms of our knowledge, not qualities of things in themselves; then we shall understand that this astonishment at the conformity to law and accurate operation of a force of nature, this astonishment at the complete sameness of all its million phenomena and the infallibility of their occurrence, is really like that of a child or a savage who looks for the first time through a glass with many facets at a flower, and marvels at the complete similarity of the innumerable flowers which he sees, and counts the leaves of each of them separately.

Thus every universal, original force of nature is nothing but a low grade of the objectification of will, and we call every such grade an eternal _Idea_ in Plato’s sense. But a _law of nature_ is the relation of the Idea to the form of its manifestation. This form is time, space, and causality, which are necessarily and inseparably connected and related to each other. Through time and space the Idea multiplies itself in innumerable phenomena, but the order according to which it enters these forms of multiplicity is definitely determined by the law of causality; this law is as it were the norm of the limit of these phenomena of different Ideas, in accordance with which time, space, and matter are assigned to them. This norm is therefore necessarily related to the identity of the aggregate of existing matter, which is the common substratum of all those different phenomena. If all these were not directed to that common matter in the possession of which they must be divided, there would be no need for such a law to decide their claims. They might all at once and together fill a boundless space throughout an endless time. Therefore, because all these phenomena of the eternal Ideas are directed to one and the same matter, must there be a rule for their appearance and disappearance; for if there were not, they would not make way for each other. Thus the law of causality is essentially bound up with that of the permanence of substance; they reciprocally derive significance from each other. Time and space, again, are related to them in the same way. For time is merely the possibility of conflicting states of the same matter, and space is merely the possibility of the permanence of the same matter under all sorts of conflicting states. Accordingly, in the preceding book we explained matter as the union of space and time, and this union shows itself as change of the accidents in the permanence of the substance, of which causality or becoming is the universal possibility. And accordingly, we said that matter is through and through causality. We explained the understanding as the subjective correlative of causality, and said matter (and thus the whole world as idea) exists only for the understanding; the understanding is its condition, its supporter as its necessary correlative. I repeat all this in passing, merely to call to mind what was demonstrated in the First Book, for it is necessary for the complete understanding of these two books that their inner agreement should be observed, since what is inseparably united in the actual world as its two sides, will and idea, has, in order that we might understand each of them more clearly in isolation, been dissevered in these two books.

It may not perhaps be superfluous to elucidate further by an example how the law of causality has meaning only in relation to time and space, and the matter which consists in the union of the two. For it determines the limits in accordance with which the phenomena of the forces of nature divide themselves in the possession of matter, while the original forces of nature, as the immediate objectification of will, which, as a thing in itself, is not subordinated to the principle of sufficient reason, lie outside these forms, within which alone all etiological explanation has validity and meaning, and just on that account can never lead us to the inner reality of nature. For this purpose let us think of some kind of machine constructed according to the laws of mechanics. Iron weights begin the motion by their gravity; copper wheels resist by their rigidity, affect and raise each other and the lever by their impenetrability, and so on. Here gravity, rigidity, and impenetrability are original unexplained forces; mechanics only gives us the condition under which, and the manner in which, they manifest themselves, appear, and govern a definite matter, time, and place. If, now, a strong magnet is made to attract the iron of the weight, and overcome its gravity, the movement of the machine stops, and the matter becomes forthwith the scene of quite a different force of nature—magnetism, of which etiology again gives no further explanation than the condition under which it appears. Or let us suppose that the copper discs of such a machine are laid upon zinc plates, and an acid solution introduced between them. At once the same matter of the machine has become subject to another original force, galvanism, which now governs it according to its own laws, and reveals itself in it through its phenomena; and etiology can again tell us nothing about this force except the conditions under which, and the laws in accordance with which, it manifests itself. Let us now raise the temperature and add pure acid; the whole machine burns; that is to say, once more an entirely different force of nature, chemical energy, asserts at this time and in this place irresistible claims to this particular matter, and reveals itself in it as Idea, as a definite grade of the objectification of will. The calcined metal thus produced now unites with an acid, and a salt is obtained which forms itself into crystals. These are the phenomena of another Idea, which in itself is again quite inexplicable, while the appearance of its phenomena is dependent upon certain conditions which etiology can give us. The crystals dissolve, mix with other materials, and vegetation springs up from them—a new phenomenon of will: and so the same permanent matter may be followed _ad infinitum_, to observe how now this and now that natural force obtains a right to it and temporarily takes possession of it, in order to appear and reveal its own nature. The condition of this right, the point of time and space at which it becomes valid, is given by causality, but the explanation founded upon this law only extends thus far. The force itself is a manifestation of will, and as such is not subject to the forms of the principle of sufficient reason, that is, it is groundless. It lies outside all time, is omnipresent, and seems as it were to wait constantly till the circumstances occur under which it can appear and take possession of a definite matter, supplanting the forces which have reigned in it till then. All time exists only for the phenomena of such a force, and is without significance for the force itself. Through thousands of years chemical forces slumber in matter till the contact with the reagents sets them free; then they appear; but time exists only for the phenomena, not for the forces themselves. For thousands of years galvanism slumbered in copper and zinc, and they lay quietly beside silver, which must be consumed in flame as soon as all three are brought together under the required conditions. Even in the organic kingdom we see a dry seed preserve the slumbering force through three thousand years, and when at last the favourable circumstances occur, grow up as a plant.(35)

If by this exposition the difference between a force of nature and all its phenomena has been made quite distinct; if we have seen clearly that the former is the will itself at this particular grade of its objectification, but that multiplicity comes to phenomena only through time and space, and that the law of causality is nothing but the determination of the position of these phenomena in time and space; then we shall recognise the complete truth and the deep meaning of Malebranche’s doctrine of occasional causes (_causes occasionelles_). It is well worth while comparing this doctrine of his, as he explains it in the “_Recherches de la Vérite_,” both in the 3rd Chapter of the second part of the 6th Book, and in the _éclaircissements_ appended to this chapter, with this exposition of mine, and observing the complete agreement of the two doctrines in the case of such different systems of thought. Indeed I cannot help admiring how Malebranche, though thoroughly involved in the positive dogmas which his age inevitably forced upon him, yet, in such bonds and under such a burden, hit the truth so happily, so correctly, and even knew how to combine it with these dogmas, at all events verbally.

For the power of truth is incredibly great and of unspeakable endurance. We find constant traces of it in all, even the most eccentric and absurd dogmas, of different times and different lands,—often indeed in strange company, curiously mixed up with other things, but still recognisable. It is like a plant that germinates under a heap of great stones, but still struggles up to the light, working itself through with many deviations and windings, disfigured, worn out, stunted in its growth,—but yet, to the light.

In any case Malebranche is right: every natural cause is only an occasional cause. It only gives opportunity or occasion for the manifestation of the one indivisible will which is the “in-itself” of all things, and whose graduated objectification is the whole visible world. Only the appearance, the becoming visible, in this place, at this time, is brought about by the cause and is so far dependent on it, but not the whole of the phenomenon, nor its inner nature. This is the will itself, to which the principle of sufficient reason has not application, and which is therefore groundless. Nothing in the world has a sufficient cause of its existence generally, but only a cause of existence just here and just now. That a stone exhibits now gravity, now rigidity, now electricity, now chemical qualities, depends upon causes, upon impressions upon it from without, and is to be explained from these. But these qualities themselves, and thus the whole inner nature of the stone which consists in them, and therefore manifests itself in all the ways referred to; thus, in general, that the stone is such as it is, that it exists generally—all this, I say, has no ground, but is the visible appearance of the groundless will. Every cause is thus an occasional cause. We have found it to be so in nature, which is without knowledge, and it is also precisely the same when motives and not causes or stimuli determine the point at which the phenomena are to appear, that is to say, in the actions of animals and human beings. For in both cases it is one and the same will which appears; very different in the grades of its manifestation, multiplied in the phenomena of these grades, and, in respect of these, subordinated to the principle of sufficient reason, but in itself free from all this. Motives do not determine the character of man, but only the phenomena of his character, that is, his actions; the outward fashion of his life, not its inner meaning and content. These proceed from the character which is the immediate manifestation of the will, and is therefore groundless. That one man is bad and another good, does not depend upon motives or outward influences, such as teaching and preaching, and is in this sense quite inexplicable. But whether a bad man shows his badness in petty acts of injustice, cowardly tricks, and low knavery which he practises in the narrow sphere of his circumstances, or whether as a conqueror he oppresses nations, throws a world into lamentation, and sheds the blood of millions; this is the outward form of his manifestation, that which is unessential to it, and depends upon the circumstances in which fate has placed him, upon his surroundings, upon external influences, upon motives; but his decision upon these motives can never be explained from them; it proceeds from the will, of which this man is a manifestation. Of this we shall speak in the Fourth Book. The manner in which the character discloses its qualities is quite analogous to the way in which those of every material body in unconscious nature are disclosed. Water remains water with its intrinsic qualities, whether as a still lake it reflects its banks, or leaps in foam from the cliffs, or, artificially confined, spouts in a long jet into the air. All that depends upon external causes; the one form is as natural to it as the other, but it will always show the same form in the same circumstances; it is equally ready for any, but in every case true to its character, and at all times revealing this alone. So will every human character under all circumstances reveal itself, but the phenomena which proceed from it will always be in accordance with the circumstances.

§ 27. If, from the foregoing consideration of the forces of nature and their phenomena, we have come to see clearly how far an explanation from causes can go, and where it must stop if it is not to degenerate into the vain attempt to reduce the content of all phenomena to their mere form, in which case there would ultimately remain nothing but form, we shall be able to settle in general terms what is to be demanded of etiology as a whole. It must seek out the causes of all phenomena in nature, _i.e._, the circumstances under which they invariably appear. Then it must refer the multitude of phenomena which have various forms in various circumstances to what is active in every phenomenon, and is presupposed in the cause,—original forces of nature. It must correctly distinguish between a difference of the phenomenon which arises from a difference of the force, and one which results merely from a difference of the circumstances under which the force expresses itself; and with equal care it must guard against taking the expressions of one and the same force under different circumstances for the manifestations of different forces, and conversely against taking for manifestations of one and the same force what originally belongs to different forces. Now this is the direct work of the faculty of judgment, and that is why so few men are capable of increasing our insight in physics, while all are able to enlarge experience. Indolence and ignorance make us disposed to appeal too soon to original forces. This is exemplified with an exaggeration that savours of irony in the entities and quidities of the schoolmen. Nothing is further from my desire than to favour their resuscitation. We have just as little right to appeal to the objectification of will, instead of giving a physical explanation, as we have to appeal to the creative power of God. For physics demands causes, and the will is never a cause. Its whole relation to the phenomenon is not in accordance with the principle of sufficient reason. But that which in itself is the will exists in another aspect as idea; that is to say, is phenomenon. As such, it obeys the laws which constitute the form of the phenomenon. Every movement, for example, although it is always a manifestation of will, must yet have a cause from which it is to be explained in relation to a particular time and space; that is, not in general in its inner nature, but as a _particular_ phenomenon. In the case of the stone, this is a mechanical cause; in that of the movement of a man, it is a motive; but in no case can it be wanting. On the other hand, the universal common nature of all phenomena of one particular kind, that which must be presupposed if the explanation from causes is to have any sense and meaning, is the general force of nature, which, in physics, must remain a _qualitas occulta_, because with it the etiological explanation ends and the metaphysical begins. But the chain of causes and effects is never broken by an original force to which it has been necessary to appeal. It does not run back to such a force as if it were its first link, but the nearest link, as well as the remotest, presupposes the original force, and could otherwise explain nothing. A series of causes and effects may be the manifestation of the most different kinds of forces, whose successive visible appearances are conducted through it, as I have illustrated above by the example of a metal machine. But the difference of these original forces, which cannot be referred to each other, by no means breaks the unity of that chain of causes, and the connection between all its links. The etiology and the philosophy of nature never do violence to each other, but go hand in hand, regarding the same object from different points of view. Etiology gives an account of the causes which necessarily produce the particular phenomenon to be explained. It exhibits, as the foundation of all its explanations, the universal forces which are active in all these causes and effects. It accurately defines, enumerates, and distinguishes these forces, and then indicates all the different effects in which each force appears, regulated by the difference of the circumstances, always in accordance with its own peculiar character, which it discloses in obedience to an invariable rule, called _a law of nature_. When all this has been thoroughly accomplished by physics in every particular, it will be complete, and its work will be done. There will then remain no unknown force in unorganised nature, nor any effect, which has not been proved to be the manifestation of one of these forces under definite circumstances, in accordance with a law of nature. Yet a law of nature remains merely the observed rule according to which nature invariably proceeds whenever certain definite circumstances occur. Therefore a law of nature may be defined as a fact expressed generally—_un fait généralisé_—and thus a complete enumeration of all the laws of nature would only be a complete register of facts. The consideration of nature as a whole is thus completed in _morphology_, which enumerates, compares, and arranges all the enduring forms of organised nature. Of the causes of the appearance of the individual creature it has little to say, for in all cases this is procreation (the theory of which is a separate matter), and in rare cases the _generatio æquivoca_. But to this last belongs, strictly speaking, the manner in which all the lower grades of the objectification of will, that is to say, physical and chemical phenomena, appear as individual, and it is precisely the task of etiology to point out the conditions of this appearance. Philosophy, on the other hand, concerns itself only with the universal, in nature as everywhere else. The original forces themselves are here its object, and it recognises in them the different grades of the objectivity of will, which is the inner nature, the “in-itself” of this world; and when it regards the world apart from will, it explains it as merely the idea of the subject. But if etiology, instead of preparing the way for philosophy, and supplying its doctrines with practical application by means of instances, supposes that its aim is rather to deny the existence of all original forces, except perhaps _one_, the most general, for example, impenetrability, which it imagines it thoroughly understands, and consequently seeks forcibly to refer all the others to it—it forsakes its own province and can only give us error instead of truth. The content of nature is supplanted by its form, everything is ascribed to the circumstances which work from without, and nothing to the inner nature of the thing. Now if it were possible to succeed by this method, a problem in arithmetic would ultimately, as we have already remarked, solve the riddle of the universe. But this is the method adopted by those, referred to above, who think that all physiological effects ought to be reduced to form and combination, this, perhaps, to electricity, and this again to chemism, and chemism to mechanism. The mistake of Descartes, for example, and of all the Atomists, was of this last description. They referred the movements of the globe to the impact of a fluid, and the qualities of matter to the connection and form of the atoms, and hence they laboured to explain all the phenomena of nature as merely manifestations of impenetrability and cohesion. Although this has been given up, precisely the same error is committed in our own day by the electrical, chemical, and mechanical physiologists, who obstinately attempt to explain the whole of life and all the functions of the organism from “form and combination.” In Meckel’s “Archiv für Physiologie” (1820, vol. v. p. 185) we still find it stated that the aim of physiological explanation is the reduction of organic life to the universal forces with which physics deals. Lamarck also, in his “_Philosophie Zoologique_,” explains life as merely the effect of warmth and electricity: _le calorique et la matière électrique suffisent parfaitement pour composer ensemble cette cause essentielle de la vie_ (p. 16). According to this, warmth and electricity would be the “thing-in-itself,” and the world of animals and plants its phenomenal appearance. The absurdity of this opinion becomes glaringly apparent at the 306th and following pages of that work. It is well known that all these opinions, that have been so often refuted, have reappeared quite recently with renewed confidence. If we carefully examine the foundation of these views, we shall find that they ultimately involve the presupposition that the organism is merely an aggregate of phenomena of physical, chemical, and mechanical forces, which have come together here by chance, and produced the organism as a freak of nature without further significance. The organism of an animal or of a human being would therefore be, if considered philosophically, not the exhibition of a special Idea, that is, not itself immediate objectivity of the will at a definite higher grade, but in it would appear only those Ideas which objectify the will in electricity, in chemism, and in mechanism. Thus the organism would be as fortuitously constructed by the concurrence of these forces as the forms of men and beasts in clouds and stalactites, and would therefore in itself be no more interesting than they are. However, we shall see immediately how far the application of physical and chemical modes of explanation to the organism may yet, within certain limits, be allowable and useful; for I shall explain that the vital force certainly avails itself of and uses the forces of unorganised nature; yet these forces no more constitute the vital force than a hammer and anvil make a blacksmith. Therefore even the most simple example of plant life can never be explained from these forces by any theory of capillary attraction and endosmose, much less animal life. The following observations will prepare the way for this somewhat difficult discussion.

It follows from all that has been said that it is certainly an error on the part of natural science to seek to refer the higher grades of the objectification of will to the lower; for the failure to recognise, or the denial of, original and self-existing forces of nature is just as wrong as the groundless assumption of special forces when what occurs is merely a peculiar kind of manifestation of what is already known. Thus Kant rightly says that it would be absurd to hope for a blade of grass from a Newton, that is, from one who reduced the blade of grass to the manifestations of physical and chemical forces, of which it was the chance product, and therefore a mere freak of nature, in which no special Idea appeared, _i.e._, the will did not directly reveal itself in it in a higher and specific grade, but just as in the phenomena of unorganised nature and by chance in this form. The schoolmen, who certainly would not have allowed such a doctrine, would rightly have said that it was a complete denial of the _forma substantialis_, and a degradation of it to the _forma accidentalis_. For the _forma substantialis_ of Aristotle denotes exactly what I call the grade of the objectification of will in a thing. On the other hand, it is not to be overlooked that in all Ideas, that is, in all forces of unorganised, and all forms of organised nature, it is _one and the same_ will that reveals itself, that is to say, which enters the form of the idea and passes into _objectivity_. Its unity must therefore be also recognisable through an inner relationship between all its phenomena. Now this reveals itself in the higher grades of the objectification of will, where the whole phenomenon is more distinct, thus in the vegetable and animal kingdoms, through the universally prevailing analogy of all forms, the fundamental type which recurs in all phenomena. This has, therefore, become the guiding principle of the admirable zoological system which was originated by the French in this century, and it is most completely established in comparative anatomy as _l’unité de plan_, _l’uniformité de l’élément anatomique_. To discover this fundamental type has been the chief concern, or at any rate the praiseworthy endeavour, of the natural philosophers of the school of Schelling, who have in this respect considerable merit, although in many cases their hunt after analogies in nature degenerated into mere conceits. They have, however, rightly shown that that general relationship and family likeness exists also in the Ideas of unorganised nature; for example, between electricity and magnetism, the identity of which was afterwards established; between chemical attraction and gravitation, and so forth. They specially called attention to the fact that _polarity_, that is, the sundering of a force into two qualitatively different and opposed activities striving after reunion, which also shows itself for the most part in space as a dispersion in opposite directions, is a fundamental type of almost all the phenomena of nature, from the magnet and the crystal to man himself. Yet this knowledge has been current in China from the earliest times, in the doctrine of opposition of Yin and Yang. Indeed, since all things in the world are the objectification of one and the same will, and therefore in their inner nature identical, it must not only be the case that there is that unmistakable analogy between them, and that in every phenomenon the trace, intimation, and plan of the higher phenomenon that lies next to it in point of development shows itself, but also because all these forms belong to the world as _idea_, it is indeed conceivable that even in the most universal forms of the idea, in that peculiar framework of the phenomenal world space and time, it may be possible to discern and establish the fundamental type, intimation, and plan of what fills the forms. It seems to have been a dim notion of this that was the origin of the Cabala and all the mathematical philosophy of the Pythagoreans, and also of the Chinese in Y-king. In the school of Schelling also, to which we have already referred, we find, among their efforts to bring to light the similarity among the phenomena of nature, several attempts (though rather unfortunate ones) to deduce laws of nature from the laws of pure space and time. However, one can never tell to what extent a man of genius will realise both endeavours.

Now, although the difference between phenomenon and thing-in-itself is never lost sight of, and therefore the identity of the will which objectifies itself in all Ideas can never (because it has different grades of its objectification) be distorted to mean identity of the particular Ideas themselves in which it appears, so that, for example, chemical or electrical attraction can never be reduced to the attraction of gravitation, although this inner analogy is known, and the former may be regarded as, so to speak, higher powers of the latter, just as little does the similarity of the construction of all animals warrant us in mixing and identifying the species and explaining the more developed as mere variations of the less developed; and although, finally, the physiological functions are never to be reduced to chemical or physical processes, yet, in justification of this procedure, within certain limits, we may accept the following observations as highly probable.

If several of the phenomena of will in the lower grades of its objectification—that is, in unorganised nature—come into conflict because each of them, under the guidance of causality, seeks to possess a given portion of matter, there arises from the conflict the phenomenon of a higher Idea which prevails over all the less developed phenomena previously there, yet in such a way that it allows the essence of these to continue to exist in a subordinate manner, in that it takes up into itself from them something which is analogous to them. This process is only intelligible from the identity of the will which manifests itself in all the Ideas, and which is always striving after higher objectification. We thus see, for example, in the hardening of the bones, an unmistakable analogy to crystallisation, as the force which originally had possession of the chalk, although ossification is never to be reduced to crystallisation. The analogy shows itself in a weaker degree in the flesh becoming firm. The combination of humours in the animal body and secretion are also analogous to chemical combination and separation. Indeed, the laws of chemistry are still strongly operative in this case, but subordinated, very much modified, and mastered by a higher Idea; therefore mere chemical forces outside the organism will never afford us such humours; but

“Encheiresin naturæ nennt es die Chemie, Spottet ihrer selbst und weiss nicht wie.”

The more developed Idea resulting from this victory over several lower Ideas or objectifications of will, gains an entirely new character by taking up into itself from every Idea over which it has prevailed a strengthened analogy. The will objectifies itself in a new, more distinct way. It originally appears in _generatio æquivoca_; afterwards in assimilation to the given germ, organic moisture, plant, animal, man. Thus from the strife of lower phenomena the higher arise, swallowing them all up, but yet realising in the higher grade the tendency of all the lower. Here, then, already the law applies—_Serpens nisi serpentem comederit non fit draco._

I wish it had been possible for me to dispel by clearness of explanation the obscurity which clings to the subject of these thoughts; but I see very well that the reader’s own consideration of the matter must materially aid me if I am not to remain uncomprehended or misunderstood. According to the view I have expressed, the traces of chemical and physical modes of operation will indeed be found in the organism, but it can never be explained from them; because it is by no means a phenomenon even accidentally brought about through the united actions of such forces, but a higher Idea which has overcome these lower ideas by _subduing assimilation_; for the _one_ will which objectifies itself in all Ideas always seeks the highest possible objectification, and has therefore in this case given up the lower grades of its manifestation after a conflict, in order to appear in a higher grade, and one so much the more powerful. No victory without conflict: since the higher Idea or objectification of will can only appear through the conquest of the lower, it endures the opposition of these lower Ideas, which, although brought into subjection, still constantly strive to obtain an independent and complete expression of their being. The magnet that has attracted a piece of iron carries on a perpetual conflict with gravitation, which, as the lower objectification of will, has a prior right to the matter of the iron; and in this constant battle the magnet indeed grows stronger, for the opposition excites it, as it were, to greater effort. In the same way every manifestation of the will, including that which expresses itself in the human organism, wages a constant war against the many physical and chemical forces which, as lower Ideas, have a prior right to that matter. Thus the arm falls which for a while, overcoming gravity, we have held stretched out; thus the pleasing sensation of health, which proclaims the victory of the Idea of the self-conscious organism over the physical and chemical laws, which originally governed the humours of the body, is so often interrupted, and is indeed always accompanied by greater or less discomfort, which arises from the resistance of these forces, and on account of which the vegetative part of our life is constantly attended by slight pain. Thus also digestion weakens all the animal functions, because it requires the whole vital force to overcome the chemical forces of nature by assimilation. Hence also in general the burden of physical life, the necessity of sleep, and, finally, of death; for at last these subdued forces of nature, assisted by circumstances, win back from the organism, wearied even by the constant victory, the matter it took from them, and attain to an unimpeded expression of their being. We may therefore say that every organism expresses the Idea of which it is the image, only after we have subtracted the part of its force which is expended in subduing the lower Ideas that strive with it for matter. This seems to have been running in the mind of Jacob Böhm when he says somewhere that all the bodies of men and animals, and even all plants, are really half dead. According as the subjection in the organism of these forces of nature, which express the lower grades of the objectification of will, is more or less successful, the more or the less completely does it attain to the expression of its Idea; that is to say, the nearer it is to the _ideal_ or the further from it—the _ideal_ of beauty in its species.

Thus everywhere in nature we see strife, conflict, and alternation of victory, and in it we shall come to recognise more distinctly that variance with itself which is essential to the will. Every grade of the objectification of will fights for the matter, the space, and the time of the others. The permanent matter must constantly change its form; for under the guidance of causality, mechanical, physical, chemical, and organic phenomena, eagerly striving to appear, wrest the matter from each other, for each desires to reveal its own Idea. This strife may be followed through the whole of nature; indeed nature exists only through it: ει γαρ μη ην το νεικος εν τοις πραγμασιν, ἑν αν ην ἁπαντα, ὡς φησιν Εμπεδοκλης; (nam si non inesset in rebus contentio, unum omnia essent, ut ait Empedocles. Aris. Metaph., B. 5). Yet this strife itself is only the revelation of that variance with itself which is essential to the will. This universal conflict becomes most distinctly visible in the animal kingdom. For animals have the whole of the vegetable kingdom for their food, and even within the animal kingdom every beast is the prey and the food of another; that is, the matter in which its Idea expresses itself must yield itself to the expression of another Idea, for each animal can only maintain its existence by the constant destruction of some other. Thus the will to live everywhere preys upon itself, and in different forms is its own nourishment, till finally the human race, because it subdues all the others, regards nature as a manufactory for its use. Yet even the human race, as we shall see in the Fourth Book, reveals in itself with most terrible distinctness this conflict, this variance with itself of the will, and we find _homo homini lupus_. Meanwhile we can recognise this strife, this subjugation, just as well in the lower grades of the objectification of will. Many insects (especially ichneumon-flies) lay their eggs on the skin, and even in the body of the larvæ of other insects, whose slow destruction is the first work of the newly hatched brood. The young hydra, which grows like a bud out of the old one, and afterwards separates itself from it, fights while it is still joined to the old one for the prey that offers itself, so that the one snatches it out of the mouth of the other (Trembley, Polypod., ii. p. 110, and iii. p. 165). But the bulldog-ant of Australia affords us the most extraordinary example of this kind; for if it is cut in two, a battle begins between the head and the tail. The head seizes the tail with its teeth, and the tail defends itself bravely by stinging the head: the battle may last for half an hour, until they die or are dragged away by other ants. This contest takes place every time the experiment is tried. (From a letter by Howitt in the W. Journal, reprinted in Galignani’s Messenger, 17th November 1855.) On the banks of the Missouri one sometimes sees a mighty oak the stem and branches of which are so encircled, fettered, and interlaced by a gigantic wild vine, that it withers as if choked. The same thing shows itself in the lowest grades; for example, when water and carbon are changed into vegetable sap, or vegetables or bread into blood by organic assimilation; and so also in every case in which animal secretion takes place, along with the restriction of chemical forces to a subordinate mode of activity. This also occurs in unorganised nature, when, for example, crystals in process of formation meet, cross, and mutually disturb each other to such an extent that they are unable to assume the pure crystalline form, so that almost every cluster of crystals is an image of such a conflict of will at this low grade of its objectification; or again, when a magnet forces its magnetism upon iron, in order to express its Idea in it; or when galvanism overcomes chemical affinity, decomposes the closest combinations, and so entirely suspends the laws of chemistry that the acid of a decomposed salt at the negative pole must pass to the positive pole without combining with the alkalies through which it goes on its way, or turning red the litmus paper that touches it. On a large scale it shows itself in the relation between the central body and the planet, for although the planet is in absolute dependence, yet it always resists, just like the chemical forces in the organism; hence arises the constant tension between centripetal and centrifugal force, which keeps the globe in motion, and is itself an example of that universal essential conflict of the manifestation of will which we are considering. For as every body must be regarded as the manifestation of a will, and as will necessarily expresses itself as a struggle, the original condition of every world that is formed into a globe cannot be rest, but motion, a striving forward in boundless space without rest and without end. Neither the law of inertia nor that of causality is opposed to this: for as, according to the former, matter as such is alike indifferent to rest and motion, its original condition may just as well be the one as the other, therefore if we first find it in motion, we have just as little right to assume that this was preceded by a condition of rest, and to inquire into the cause of the origin of the motion, as, conversely, if we found it at rest, we would have to assume a previous motion and inquire into the cause of its suspension. It is, therefore, not needful to seek for a first impulse for centrifugal force, for, according to the hypothesis of Kant and Laplace, it is, in the case of the planets, the residue of the original rotation of the central body, from which the planets have separated themselves as it contracted. But to this central body itself motion is essential; it always continues its rotation, and at the same time rushes forward in endless space, or perhaps circulates round a greater central body invisible to us. This view entirely agrees with the conjecture of astronomers that there is a central sun, and also with the observed advance of our whole solar system, and perhaps of the whole stellar system to which our sun belongs. From this we are finally led to assume a general advance of fixed stars, together with the central sun, and this certainly loses all meaning in boundless space (for motion in absolute space cannot be distinguished from rest), and becomes, as is already the case from its striving and aimless flight, an expression of that nothingness, that failure of all aim, which, at the close of this book, we shall be obliged to recognise in the striving of will in all its phenomena. Thus boundless space and endless time must be the most universal and essential forms of the collective phenomena of will, which exist for the expression of its whole being. Lastly, we can recognise that conflict which we are considering of all phenomena of will against each other in simple matter regarded as such; for the real characteristic of matter is correctly expressed by Kant as repulsive and attractive force; so that even crude matter has its existence only in the strife of conflicting forces. If we abstract from all chemical differences in matter, or go so far back in the chain of causes and effects that as yet there is no chemical difference, there remains mere matter,—the world rounded to a globe, whose life, _i.e._, objectification of will, is now constituted by the conflict between attractive and repulsive forces, the former as gravitation pressing from all sides towards the centre, the latter as impenetrability always opposing the former either as rigidity or elasticity; and this constant pressure and resistance may be regarded as the objectivity of will in its very lowest grade, and even there it expresses its character.

We should see the will express itself here in the lowest grade as blind striving, an obscure, inarticulate impulse, far from susceptible of being directly known. It is the simplest and the weakest mode of its objectification. But it appears as this blind and unconscious striving in the whole of unorganised nature, in all those original forces of which it is the work of physics and chemistry to discover and to study the laws, and each of which manifests itself to us in millions of phenomena which are exactly similar and regular, and show no trace of individual character, but are mere multiplicity through space and time, _i.e._, through the _principium individuationis_, as a picture is multiplied through the facets of a glass.

From grade to grade objectifying itself more distinctly, yet still completely without consciousness as an obscure striving force, the will acts in the vegetable kingdom also, in which the bond of its phenomena consists no longer properly of causes, but of stimuli; and, finally, also in the vegetative part of the animal phenomenon, in the production and maturing of the animal, and in sustaining its inner economy, in which the manifestation of will is still always necessarily determined by stimuli. The ever-ascending grades of the objectification of will bring us at last to the point at which the individual that expresses the Idea could no longer receive food for its assimilation through mere movement following upon stimuli. For such a stimulus must be waited for, but the food has now come to be of a more special and definite kind, and with the ever-increasing multiplicity of the individual phenomena, the crowd and confusion has become so great that they interfere with each other, and the chance of the individual that is moved merely by stimuli and must wait for its food would be too unfavourable. From the point, therefore, at which the animal has delivered itself from the egg or the womb in which it vegetated without consciousness, its food must be sought out and selected. For this purpose movement following upon motives, and therefore consciousness, becomes necessary, and consequently it appears as an agent, μηχανη, called in at this stage of the objectification of will for the conservation of the individual and the propagation of the species. It appears represented by the brain or a large ganglion, just as every other effort or determination of the will which objectifies itself is represented by an organ, that is to say, manifests itself for the idea as an organ.(36) But with this means of assistance, this μηχανη, the _world as idea_ comes into existence at a stroke, with all its forms, object and subject, time, space, multiplicity, and causality. The world now shows its second side. Till now _mere will_, it becomes also _idea_, object of the knowing subject. The will, which up to this point followed its tendency in the dark with unerring certainty, has at this grade kindled for itself a light as a means which became necessary for getting rid of the disadvantage which arose from the throng and the complicated nature of its manifestations, and which would have accrued precisely to the most perfect of them. The hitherto infallible certainty and regularity with which it worked in unorganised and merely vegetative nature, rested upon the fact that it alone was active in its original nature, as blind impulse, will, without assistance, and also without interruption, from a second and entirely different world, the world as idea, which is indeed only the image of its own inner being, but is yet of quite another nature, and now encroaches on the connected whole of its phenomena. Hence its infallible certainty comes to an end. Animals are already exposed to illusion, to deception. They have, however, merely ideas of perception, no conceptions, no reflection, and they are therefore bound to the present; they cannot have regard for the future. It seems as if this knowledge without reason was not in all cases sufficient for its end, and at times required, as it were, some assistance. For the very remarkable phenomenon presents itself, that the blind working of the will and the activity enlightened by knowledge encroach in a most astonishing manner upon each other’s spheres in two kinds of phenomena. In the one case we find in the very midst of those actions of animals which are guided by perceptive knowledge and its motives one kind of action which is accomplished apart from these, and thus through the necessity of the blindly acting will. I refer to those mechanical instincts which are guided by no motive or knowledge, and which yet have the appearance of performing their work from abstract rational motives. The other case, which is opposed to this, is that in which, on the contrary, the light of knowledge penetrates into the workshop of the blindly active will, and illuminates the vegetative functions of the human organism. I mean clairvoyance. Finally, when the will has attained to the highest grade of its objectification, that knowledge of the understanding given to brutes to which the senses supply the data, out of which there arises mere perception confined to what is immediately present, does not suffice. That complicated, many-sided, imaginative being, man, with his many needs, and exposed as he is to innumerable dangers, must, in order to exist, be lighted by a double knowledge; a higher power, as it were, of perceptive knowledge must be given him, and also reason, as the faculty of framing abstract conceptions. With this there has appeared reflection, surveying the future and the past, and, as a consequence, deliberation, care, the power of premeditated action independent of the present, and finally, the full and distinct consciousness of one’s own deliberate volition as such. Now if with mere knowledge of perception there arose the possibility of illusion and deception, by which the previous infallibility of the blind striving of will was done away with, so that mechanical and other instincts, as expressions of unconscious will, had to lend their help in the midst of those that were conscious, with the entrance of reason that certainty and infallibility of the expressions of will (which at the other extreme in unorganised nature appeared as strict conformity to law) is almost entirely lost; instinct disappears altogether; deliberation, which is supposed to take the place of everything else, begets (as was shown in the First Book) irresolution and uncertainty; then error becomes possible, and in many cases obstructs the adequate objectification of the will in action. For although in the character the will has already taken its definite and unchangeable bent or direction, in accordance with which volition, when occasioned by the presence of a motive, invariably takes place, yet error can falsify its expressions, for it introduces illusive motives that take the place of the real ones which they resemble;(37) as, for example, when superstition forces on a man imaginary motives which impel him to a course of action directly opposed to the way in which the will would otherwise express itself in the given circumstances. Agamemnon slays his daughter; a miser dispenses alms, out of pure egotism, in the hope that he will some day receive an hundred-fold; and so on.

Thus knowledge generally, rational as well as merely sensuous, proceeds originally from the will itself, belongs to the inner being of the higher grades of its objectification as a mere μηχανη, a means of supporting the individual and the species, just like any organ of the body. Originally destined for the service of the will for the accomplishment of its aims, it remains almost throughout entirely subjected to its service: it is so in all brutes and in almost all men. Yet we shall see in the Third Book how in certain individual men knowledge can deliver itself from this bondage, throw off its yoke, and, free from all the aims of will, exist purely for itself, simply as a clear mirror of the world, which is the source of art. Finally, in the Fourth Book, we shall see how, if this kind of knowledge reacts on the will, it can bring about self-surrender, _i.e._, resignation, which is the final goal, and indeed the inmost nature of all virtue and holiness, and is deliverance from the world.

§ 28. We have considered the great multiplicity and diversity of the phenomena in which the will objectifies itself, and we have seen their endless and implacable strife with each other. Yet, according to the whole discussion up to this point, the will itself, as thing-in-itself, is by no means included in that multiplicity and change. The diversity of the (Platonic) Ideas, _i.e._, grades of objectification, the multitude of individuals in which each of these expresses itself, the struggle of forms for matter,—all this does not concern it, but is only the manner of its objectification, and only through this has an indirect relation to it, by virtue of which it belongs to the expression of the nature of will for the idea. As the magic-lantern shows many different pictures, which are all made visible by one and the same light, so in all the multifarious phenomena which fill the world together or throng after each other as events, only _one will_ manifests itself, of which everything is the visibility, the objectivity, and which remains unmoved in the midst of this change; it alone is thing-in-itself; all objects are manifestations, or, to speak the language of Kant, phenomena. Although in man, as (Platonic) Idea, the will finds its clearest and fullest objectification, yet man alone could not express its being. In order to manifest the full significance of the will, the Idea of man would need to appear, not alone and sundered from everything else, but accompanied by the whole series of grades, down through all the forms of animals, through the vegetable kingdom to unorganised nature. All these supplement each other in the complete objectification of will; they are as much presupposed by the Idea of man as the blossoms of a tree presuppose leaves, branches, stem, and root; they form a pyramid, of which man is the apex. If fond of similes, one might also say that their manifestations accompany that of man as necessarily as the full daylight is accompanied by all the gradations of twilight, through which, little by little, it loses itself in darkness; or one might call them the echo of man, and say: Animal and plant are the descending fifth and third of man, the inorganic kingdom is the lower octave. The full truth of this last comparison will only become clear to us when, in the following book, we attempt to fathom the deep significance of music, and see how a connected, progressive melody, made up of high, quick notes, may be regarded as in some sense expressing the life and efforts of man connected by reflection, while the unconnected complemental notes and the slow bass, which make up the harmony necessary to perfect the music, represent the rest of the animal kingdom and the whole of nature that is without knowledge. But of this in its own place, where it will not sound so paradoxical. We find, however, that the _inner necessity_ of the gradation of its manifestations, which is inseparable from the adequate objectification of the will, is expressed by an _outer necessity_ in the whole of these manifestations themselves, by reason of which man has need of the beasts for his support, the beasts in their grades have need of each other as well as of plants, which in their turn require the ground, water, chemical elements and their combinations, the planet, the sun, rotation and motion round the sun, the curve of the ellipse, &c., &c. At bottom this results from the fact that the will must live on itself, for there exists nothing beside it, and it is a hungry will. Hence arise eager pursuit, anxiety, and suffering.

It is only the knowledge of the unity of will as thing-in-itself, in the endless diversity and multiplicity of the phenomena, that can afford us the true explanation of that wonderful, unmistakable analogy of all the productions of nature, that family likeness on account of which we may regard them as variations on the same ungiven theme. So in like measure, through the distinct and thoroughly comprehended knowledge of that harmony, that essential connection of all the parts of the world, that necessity of their gradation which we have just been considering, we shall obtain a true and sufficient insight into the inner nature and meaning of the undeniable _teleology_ of all organised productions of nature, which, indeed, we presupposed _a priori_, when considering and investigating them.

This _teleology_ is of a twofold description; sometimes an _inner teleology_, that is, an agreement of all the parts of a particular organism, so ordered that the sustenance of the individual and the species results from it, and therefore presents itself as the end of that disposition or arrangement. Sometimes, however, there is an _outward teleology_, a relation of unorganised to organised nature in general, or of particular parts of organised nature to each other, which makes the maintenance of the whole of organised nature, or of the particular animal species, possible, and therefore presents itself to our judgment as the means to this end.

_Inner teleology_ is connected with the scheme of our work in the following way. If, in accordance with what has been said, all variations of form in nature, and all multiplicity of individuals, belong not to the will itself, but merely to its objectivity and the form of this objectivity, it necessarily follows that the will is indivisible and is present as a whole in every manifestation, although the grades of its objectification, the (Platonic) Ideas, are very different from each other. We may, for the sake of simplicity, regard these different Ideas as in themselves individual and simple acts of the will, in which it expresses its nature more or less. Individuals, however, are again manifestations of the Ideas, thus of these acts, in time, space, and multiplicity. Now, in the lowest grades of objectivity, such an act (or an Idea) retains its unity in the manifestation; while, in order to appear in higher grades, it requires a whole series of conditions and developments in time, which only collectively express its nature completely. Thus, for example the Idea that reveals itself in any general force of nature has always one single expression, although it presents itself differently according to the external relations that are present: otherwise its identity could not be proved, for this is done by abstracting the diversity that arises merely from external relations. In the same way the crystal has only _one_ manifestation of life, crystallisation, which afterwards has its fully adequate and exhaustive expression in the rigid form, the corpse of that momentary life. The plant, however, does not express the Idea, whose phenomenon it is, at once and through a single manifestation, but in a succession of developments of its organs in time. The animal not only develops its organism in the same manner, in a succession of forms which are often very different (metamorphosis), but this form itself, although it is already objectivity of will at this grade, does not attain to a full expression of its Idea. This expression must be completed through the

## actions of the animal, in which its empirical character, common to the

whole species, manifests itself, and only then does it become the full revelation of the Idea, a revelation which presupposes the particular organism as its first condition. In the case of man, the empirical character is peculiar to every individual (indeed, as we shall see in the Fourth Book, even to the extent of supplanting entirely the character of the species, through the self-surrender of the whole will). That which is known as the empirical character, through the necessary development in time, and the division into particular actions that is conditioned by it, is, when we abstract from this temporal form of the manifestation the _intelligible character_, according to the expression of Kant, who shows his undying merit especially in establishing this distinction and explaining the relation between freedom and necessity, _i.e._, between the will as thing-in-itself and its manifestations in time.(38) Thus the intelligible character coincides with the Idea, or, more accurately, with the original act of will which reveals itself in it. So far then, not only the empirical character of every man, but also that of every species of animal and plant, and even of every original force of unorganised nature, is to be regarded as the manifestation of an intelligible character, that is, of a timeless, indivisible act of will. I should like here to draw attention in passing to the naïveté with which every plant expresses and lays open its whole character in its mere form, reveals its whole being and will. This is why the physiognomy of plants is so interesting; while in order to know an animal in its Idea, it is necessary to observe the course of its action. As for man, he must be fully investigated and tested, for reason makes him capable of a high degree of dissimulation. The beast is as much more naïve than the man as the plant is more naïve than the beast. In the beast we see the will to live more naked, as it were, than in the man, in whom it is clothed with so much knowledge, and is, moreover, so veiled through the capacity for dissimulation, that it is almost only by chance, and here and there, that its true nature becomes apparent. In the plant it shows itself quite naked, but also much weaker, as mere blind striving for existence without end or aim. For the plant reveals its whole being at the first glance, and with complete innocence, which does not suffer from the fact that it carries its organs of generation exposed to view on its upper surface, though in all animals they have been assigned to the most hidden part. This innocence of the plant results from its complete want of knowledge. Guilt does not lie in willing, but in willing with knowledge. Every plant speaks to us first of all of its home, of the climate, and the nature of the ground in which it has grown. Therefore, even those who have had little practice easily tell whether an exotic plant belongs to the tropical or the temperate zone, and whether it grows in water, in marshes, on mountain, or on moorland. Besides this, however, every plant expresses the special will of its species, and says something that cannot be uttered in any other tongue. But we must now apply what has been said to the teleological consideration of the organism, so far as it concerns its inner design. If in unorganised nature the Idea, which is everywhere to be regarded as a single act of will, reveals itself also in a single manifestation which is always the same, and thus one may say that here the empirical character directly partakes of the unity of the intelligible, coincides, as it were, with it, so that no inner design can show itself here; if, on the contrary, all organisms express their Ideas through a series of successive developments, conditioned by a multiplicity of co-existing parts, and thus only the sum of the manifestations of the empirical character collectively constitute the expression of the intelligible character; this necessary co-existence of the parts and succession of the stages of development does not destroy the unity of the appearing Idea, the act of will which expresses itself; nay, rather this unity finds its expression in the necessary relation and connection of the parts and stages of development with each other, in accordance with the law of causality. Since it is the will which is one, indivisible, and therefore entirely in harmony with itself, that reveals itself in the whole Idea as in act, its manifestation, although broken up into a number of different parts and conditions, must yet show this unity again in the thorough agreement of all of these. This is effected by a necessary relation and dependence of all the parts upon each other, by means of which the unity of the Idea is re-established in the manifestation. In accordance with this, we now recognise these different parts and functions of the organism as related to each other reciprocally as means and end, but the organism itself as the final end of all. Consequently, neither the breaking up of the Idea, which in itself is simple, into the multiplicity of the parts and conditions of the organism, on the one hand, nor, on the other hand, the re-establishment of its unity through the necessary connection of the parts and functions which arises from the fact that they are the cause and effect, the means and end, of each other, is peculiar and essential to the appearing will as such, to the thing-in-itself, but only to its manifestation in space, time, and causality (mere modes of the principle of sufficient reason, the form of the phenomenon). They belong to the world as idea, not to the world as will; they belong to the way in which the will becomes object, _i.e._, idea at this grade of its objectivity. Every one who has grasped the meaning of this discussion—a discussion which is perhaps somewhat difficult—will now fully understand the doctrine of Kant, which follows from it, that both the design of organised and the conformity to law of unorganised nature are only introduced by our understanding, and therefore both belong only to the phenomenon, not to the thing-in-itself. The surprise, which was referred to above, at the infallible constancy of the conformity to law of unorganised nature, is essentially the same as the surprise that is excited by design in organised nature; for in both cases what we wonder at is only the sight of the original unity of the Idea, which, for the phenomenon, has assumed the form of multiplicity and diversity.(39)

As regards the second kind of teleology, according to the division made above, the _outer_ design, which shows itself, not in the inner economy of the organisms, but in the support and assistance they receive from without, both from unorganised nature and from each other; its general explanation is to be found in the exposition we have just given. For the whole world, with all its phenomena, is the objectivity of the one indivisible will, the Idea, which is related to all other Ideas as harmony is related to the single voice. Therefore that unity of the will must show itself also in the agreement of all its manifestations. But we can very much increase the clearness of this insight if we go somewhat more closely into the manifestations of that outer teleology and agreement of the different parts of nature with each other, an inquiry which will also throw some light on the foregoing exposition. We shall best attain this end by considering the following analogy.

The character of each individual man, so far as it is thoroughly individual, and not entirely included in that of the species, may be regarded as a special Idea, corresponding to a special act of the objectification of will. This act itself would then be his intelligible character, and his empirical character would be the manifestation of it. The empirical character is entirely determined through the intelligible, which is without ground, _i.e._, as thing-in-itself is not subordinated to the principle of sufficient reason (the form of the phenomenon). The empirical character must in the course of life afford us the express image of the intelligible, and can only become what the nature of the latter demands. But this property extends only to the essential, not to the unessential in the course of life to which it applies. To this unessential belong the detailed events and actions which are the material in which the empirical character shows itself. These are determined by outward circumstances, which present the motives upon which the character reacts according to its nature; and as they may be very different, the outward form of the manifestation of the empirical character, that is, the definite actual or historical form of the course of life, will have to accommodate itself to their influence. Now this form may be very different, although what is essential to the manifestation, its content, remains the same. Thus, for example it is immaterial whether a man plays for nuts or for crowns; but whether a man cheats or plays fairly, that is the real matter; the latter is determined by the intelligible character, the former by outward circumstances. As the same theme may be expressed in a hundred different variations, so the same character may be expressed in a hundred very different lives. But various as the outward influence may be, the empirical character which expresses itself in the course of life must yet, whatever form it takes, accurately objectify the intelligible character, for the latter adapts its objectification to the given material of actual circumstances. We have now to assume something analogous to the influence of outward circumstances upon the life that is determined in essential matters by the character, if we desire to understand how the will, in the original act of its objectification, determines the various Ideas in which it objectifies itself, that is, the different forms of natural existence of every kind, among which it distributes its objectification, and which must therefore necessarily have a relation to each other in the manifestation. We must assume that between all these manifestations of the _one_ will there existed a universal and reciprocal adaptation and accommodation of themselves to each other, by which, however, as we shall soon see more clearly, all time-determination is to be excluded, for the Idea lies outside time. In accordance with this, every manifestation must have adapted itself to the surroundings into which it entered, and these again must have adapted themselves to it, although it occupied a much later position in time; and we see this _consensus naturæ_ everywhere. Every plant is therefore adapted to its soil and climate, every animal to its element and the prey that will be its food, and is also in some way protected, to a certain extent, against its natural enemy: the eye is adapted to the light and its refrangibility, the lungs and the blood to the air, the air-bladder of fish to water, the eye of the seal to the change of the medium in which it must see, the water-pouch in the stomach of the camel to the drought of the African deserts, the sail of the nautilus to the wind that is to drive its little bark, and so on down to the most special and astonishing outward adaptations.(40) We must abstract however here from all temporal relations, for these can only concern the manifestation of the Idea, not the Idea itself. Accordingly this kind of explanation must also be used retrospectively, and we must not merely admit that every species accommodated itself to the given environment, but also that this environment itself, which preceded it in time, had just as much regard for the being that would some time come into it. For it is one and the same will that objectifies itself in the whole world; it knows no time, for this form of the principle of sufficient reason does not belong to it, nor to its original objectivity, the Ideas, but only to the way in which these are known by the individuals who themselves are transitory, _i.e._, to the manifestation of the Ideas. Thus, time has no significance for our present examination of the manner in which the objectification of the will distributes itself among the Ideas, and the Ideas whose _manifestations_ entered into the course of time earlier, according to the law of causality, to which as phenomena they are subject, have no advantage over those whose manifestation entered later; nay rather, these last are the completest objectifications of the will, to which the earlier manifestations must adapt themselves just as much as they must adapt themselves to the earlier. Thus the course of the planets, the tendency to the ellipse, the rotation of the earth, the division of land and sea, the atmosphere, light, warmth, and all such phenomena, which are in nature what bass is in harmony, adapted themselves in anticipation of the coming species of living creatures of which they were to become the supporter and sustainer. In the same way the ground adapted itself to the nutrition of plants, plants adapted themselves to the nutrition of animals, animals to that of other animals, and conversely they all adapted themselves to the nutrition of the ground. All the parts of nature correspond to each other, for it is _one_ will that appears in them all, but the course of time is quite foreign to its original and only _adequate objectification_ (this expression will be explained in the following book), the Ideas. Even now, when the species have only to sustain themselves, no longer to come into existence, we see here and there some such forethought of nature extending to the future, and abstracting as it were from the process of time, a self-adaptation of what is to what is yet to come. The bird builds the nest for the young which it does not yet know; the beaver constructs a dam the object of which is unknown to it; ants, marmots, and bees lay in provision for the winter they have never experienced; the spider and the ant-lion make snares, as if with deliberate cunning, for future unknown prey; insects deposit their eggs where the coming brood finds future nourishment. In the spring-time the female flower of the diœcian valisneria unwinds the spirals of its stalk, by which till now it was held at the bottom of the water, and thus rises to the surface. Just then the male flower, which grows on a short stalk from the bottom, breaks away, and so, at the sacrifice of its life, reaches the surface, where it swims about in search of the female. The latter is fructified, and then draws itself down again to the bottom by contracting its spirals, and there the fruit grows.(41) I must again refer here to the larva of the male stag-beetle, which makes the hole in the wood for its metamorphosis as big again as the female does, in order to have room for its future horns. The instinct of animals in general gives us the best illustration of what remains of teleology in nature. For as instinct is an action, like that which is guided by the conception of an end, and yet is entirely without this; so all construction of nature resembles that which is guided by the conception of an end, and yet is entirely without it. For in the outer as in the inner teleology of nature, what we are obliged to think as means and end is, in every case, _the manifestation of the unity of the one will so thoroughly agreeing with itself_, which has assumed multiplicity in space and time for our manner of knowing.

The reciprocal adaptation and self-accommodation of phenomena that springs from this unity cannot, however, annul the inner contradiction which appears in the universal conflict of nature described above, and which is essential to the will. That harmony goes only so far as to render possible the duration of the world and the different kinds of existences in it, which without it would long since have perished. Therefore it only extends to the continuance of the species, and the general conditions of life, but not to that of the individual. If, then, by reason of that harmony and accommodation, the _species_ in organised nature and the _universal forces_ in unorganised nature continue to exist beside each other, and indeed support each other reciprocally, on the other hand, the inner contradiction of the will which objectifies itself in all these ideas shows itself in the ceaseless internecine war of the _individuals_ of these species, and in the constant struggle of the _manifestations_ of these natural forces with each other, as we pointed out above. The scene and the object of this conflict is matter, which they try to wrest from each other, and also space and time, the combination of which through the form of causality is, in fact, matter, as was explained in the First Book.(42)

§ 29. I here conclude the second principal division of my exposition, in the hope that, so far as is possible in the case of an entirely new thought, which cannot be quite free from traces of the individuality in which it originated, I have succeeded in conveying to the reader the complete certainty that this world in which we live and have our being is in its whole nature through and through _will_, and at the same time through and through _idea_: that this idea, as such, already presupposes a form, object and subject, is therefore relative; and if we ask what remains if we take away this form, and all those forms which are subordinate to it, and which express the principle of sufficient reason, the answer must be that as something _toto genere_ different from idea, this can be nothing but _will_, which is thus properly the _thing-in-itself_. Every one finds that he himself is this will, in which the real nature of the world consists, and he also finds that he is the knowing subject, whose idea the whole world is, the world which exists only in relation to his consciousness, as its necessary supporter. Every one is thus himself in a double aspect the whole world, the microcosm; finds both sides whole and complete in himself. And what he thus recognises as his own real being also exhausts the being of the whole world—the macrocosm; thus the world, like man, is through and through _will_, and through and through _idea_, and nothing more than this. So we see the philosophy of Thales, which concerned the macrocosm, unite at this point with that of Socrates, which dealt with the microcosm, for the object of both is found to be the same. But all the knowledge that has been communicated in the two first books will gain greater completeness, and consequently greater certainty, from the two following books, in which I hope that several questions that have more or less distinctly arisen in the course of our work will also be sufficiently answered.

In the meantime _one_ such question may be more particularly considered, for it can only properly arise so long as one has not fully penetrated the meaning of the foregoing exposition, and may so far serve as an illustration of it. It is this: Every will is a will towards something, has an object, an end of its willing; what then is the final end, or towards what is that will striving that is exhibited to us as the being-in-itself of the world? This question rests, like so many others, upon the confusion of the thing-in-itself with the manifestation. The principle of sufficient reason, of which the law of motivation is also a form, extends only to the latter, not to the former. It is only of phenomena, of individual things, that a ground can be given, never of the will itself, nor of the Idea in which it adequately objectifies itself. So then of every particular movement or change of any kind in nature, a cause is to be sought, that is, a condition that of necessity produced it, but never of the natural force itself which is revealed in this and innumerable similar phenomena; and it is therefore simple misunderstanding, arising from want of consideration, to ask for a cause of gravity, electricity, and so on. Only if one had somehow shown that gravity and electricity were not original special forces of nature, but only the manifestations of a more general force already known, would it be allowable to ask for the cause which made this force produce the phenomena of gravity or of electricity here. All this has been explained at length above. In the same way every particular act of will of a knowing individual (which is itself only a manifestation of will as the thing-in-itself) has necessarily a motive without which that act would never have occurred; but just as material causes contain merely the determination that at this time, in this place, and in this matter, a manifestation of this or that natural force must take place, so the motive determines only the act of will of a knowing being, at this time, in this place, and under these circumstances, as a particular act, but by no means determines that that being wills in general or wills in this manner; this is the expression of his intelligible character, which, as will itself, the thing-in-itself, is without ground, for it lies outside the province of the principle of sufficient reason. Therefore every man has permanent aims and motives by which he guides his conduct, and he can always give an account of his particular actions; but if he were asked why he wills at all, or why in general he wills to exist, he would have no answer, and the question would indeed seem to him meaningless; and this would be just the expression of his consciousness that he himself is nothing but will, whose willing stands by itself and requires more particular determination by motives only in its individual acts at each point of time.

In fact, freedom from all aim, from all limits, belongs to the nature of the will, which is an endless striving. This was already touched on above in the reference to centrifugal force. It also discloses itself in its simplest form in the lowest grade of the objectification of will, in gravitation, which we see constantly exerting itself, though a final goal is obviously impossible for it. For if, according to its will, all existing matter were collected in one mass, yet within this mass gravity, ever striving towards the centre, would still wage war with impenetrability as rigidity or elasticity. The tendency of matter can therefore only be confined, never completed or appeased. But this is precisely the case with all tendencies of all phenomena of will. Every attained end is also the beginning of a new course, and so on _ad infinitum_. The plant raises its manifestation from the seed through the stem and the leaf to the blossom and the fruit, which again is the beginning of a new seed, a new individual, that runs through the old course, and so on through endless time. Such also is the life of the animal; procreation is its highest point, and after attaining to it, the life of the first individual quickly or slowly sinks, while a new life ensures to nature the endurance of the species and repeats the same phenomena. Indeed, the constant renewal of the matter of every organism is also to be regarded as merely the manifestation of this continual pressure and change, and physiologists are now ceasing to hold that it is the necessary reparation of the matter wasted in motion, for the possible wearing out of the machine can by no means be equivalent to the support it is constantly receiving through nourishment. Eternal becoming, endless flux, characterises the revelation of the inner nature of will. Finally, the same thing shows itself in human endeavours and desires, which always delude us by presenting their satisfaction as the final end of will. As soon as we attain to them they no longer appear the same, and therefore they soon grow stale, are forgotten, and though not openly disowned, are yet always thrown aside as vanished illusions. We are fortunate enough if there still remains something to wish for and to strive after, that the game may be kept up of constant transition from desire to satisfaction, and from satisfaction to a new desire, the rapid course of which is called happiness, and the slow course sorrow, and does not sink into that stagnation that shows itself in fearful ennui that paralyses life, vain yearning without a definite object, deadening languor. According to all this, when the will is enlightened by knowledge, it always knows what it wills now and here, never what it wills in general; every particular act of will has its end, the whole will has none; just as every particular phenomenon of nature is determined by a sufficient cause so far as concerns its appearance in this place at this time, but the force which manifests itself in it has no general cause, for it belongs to the thing-in-itself, to the groundless will. The single example of self-knowledge of the will as a whole is the idea as a whole, the whole world of perception. It is the objectification, the revelation, the mirror of the will. What the will expresses in it will be the subject of our further consideration.(43)

THIRD BOOK. THE WORLD AS IDEA.

Second Aspect. The Idea Independent Of The Principle Of Sufficient Reason: The Platonic Idea: The Object Of Art.

Τί τὸ ὄν μὲν ἀεί, γένεσιν δὲ οὐκ ἔχον; καὶ τί τό γιγνόμενον μὲν καὶ ἀπολλύμενον, ὄντως δε οὐδέποτε ὄν.——ΠΛΑΤΩΝ.

§ 30. In the First Book the world was explained as mere _idea_, object for a subject. In the Second Book we considered it from its other side, and found that in this aspect it is _will_, which proved to be simply that which this world is besides being idea. In accordance with this knowledge we called the world as idea, both as a whole and in its parts, the _objectification of will_, which therefore means the will become object, _i.e._, idea. Further, we remember that this objectification of will was found to have many definite grades, in which, with gradually increasing distinctness and completeness, the nature of will appears in the idea, that is to say, presents itself as object. In these grades we already recognised the Platonic Ideas, for the grades are just the determined species, or the original unchanging forms and qualities of all natural bodies, both organised and unorganised, and also the general forces which reveal themselves according to natural laws. These Ideas, then, as a whole express themselves in innumerable individuals and particulars, and are related to these as archetypes to their copies. The multiplicity of such individuals is only conceivable through time and space, their appearing and passing away through causality, and in all these forms we recognise merely the different modes of the principle of sufficient reason, which is the ultimate principle of all that is finite, of all individual existence, and the universal form of the idea as it appears in the knowledge of the individual as such. The Platonic Idea, on the other hand, does not come under this principle, and has therefore neither multiplicity nor change. While the individuals in which it expresses itself are innumerable, and unceasingly come into being and pass away, it remains unchanged as one and the same, and the principle of sufficient reason has for it no meaning. As, however, this is the form under which all knowledge of the subject comes, so far as the subject knows as an _individual_, the Ideas lie quite outside the sphere of its knowledge. If, therefore, the Ideas are to become objects of knowledge, this can only happen by transcending the individuality of the knowing subject. The more exact and detailed explanation of this is what will now occupy our attention.

§ 31. First, however, the following very essential remark. I hope that in the preceding