Part 9

The doctrine of ideas appears in the Parmenides as the positive consequence and progressive development of the Eleatic principle. Indeed in this dialogue, in that Plato makes Parmenides the chief speaker, he seems willing to allow that his doctrine is in substance that of the Eleatic sage. True, the fundamental thought of the dialogue—that the one is not conceivable in its complete singleness without the many, nor the many without the one, that each necessarily presupposes and reciprocally conditions the other—stands in the most direct contradiction to Eleaticism. Yet Parmenides himself, by dividing his poem into two parts, and treating in the first of the one and in the second of the many, postulates an inner mediation between these two externally so disjointed parts of his philosophy, and in this respect the Platonic theory of ideas might give itself out as the farther elimination, and the true sense of the Parmenidean philosophizing. This dialectical mediation between the one and the not-one or the many Plato now attempts in four antinomies, which have ostensibly only a negative result in so far as they show that contradictions arise both whether the one be adopted or rejected. The positive sense of these antinomies, though it can be gained only through inferences which Plato himself does not expressly utter, but leaves to be drawn by the reader—is as follows. The first antinomy shows that the one is inconceivable as such since it is only apprehended in its abstract opposition to the many; the second, that in this case also the reality of the many is inconceivable; the third, that the one or the idea cannot be conceived as not-being, since there can be neither conception nor predicate of the absolute not-being, and since, if not-being is excluded from all fellowship with being, all becoming and departing, all similarity and difference, every representation and explanation concerning it must also be denied; and lastly, the fourth affirms that the not-one or the many cannot be conceived without the one or the idea. What now is Plato’s aim in this discussion of the dialectic relations between the conceptions of the one and the many? Would he use the conception of the one only as an example to explain his dialectic method with conceptions, or is the discussion of this conception itself the very object before him? Manifestly the latter, or the dialogue ends without result and without any inner connection of its two parts. But how came Plato to make such a special investigation of this conception of the one? If we bear in mind that the Eleatics had already perceived the antithesis of the actual and the phenomenal world in the antithesis of the one and the many, and that Plato himself had also regarded his ideas as the unity of the manifold, as the one and the same in the many—since he repeatedly uses “idea” and “the one” in the same sense, and places (_Rep._ VII. 537) dialectics in the same rank with the faculty of bringing many to unity—then is it clear that the one which is made an object of investigation in the Parmenides is the idea in its general sense, _i. e._ in its logical form, and that Plato consequently in the dialectic of the one and the many would represent the dialectic of the idea and the phenomenal world, or in other words would dialectically determine and establish the correct view of the idea as the unity in the manifoldness of the phenomenal. In that it is shown in the Parmenides, on the one side, that the many cannot be conceived without the one, and on the other side, that the one must be something which embraces in itself manifoldness, so have we the ready inference on the one side, that the phenomenal world, or the many, has a true being only in so far as it has the one or the conception within it, and on the other side, that since the conception is not an abstract one but manifoldness in unity, it must actually have manifoldness in unity in order to be able to be in the phenomenal world. The indirect result of the Parmenides is that matter as the infinitely divisible and undetermined mass has no actuality, but is in relation to the ideal world a not-being, and though the ideas as the true being gain their appearance in it, yet the idea itself is all that is actual in the appearance or phenomenon; the phenomenal world derives its whole existence from the ideal world which appears in it, and has a being only so far as it has a conception or idea for its content.

4. POSITIVE EXPOSITION OF THE DOCTRINE OF IDEAS.—Ideas may be defined according to the different sides of their historical connection, as the common in the manifold, the universal in the particular, the one in the many, or the constant and abiding in the changing. Subjectively they are principles of knowing which cannot be derived from experience they are the intuitively certain and innate regulators of our knowledge. Objectively they are the immutable principles of being and of the phenomenal world, incorporeal and simple unities which have no relation to space, and which may be predicated of every independent thing. The doctrine of ideas grew originally out of the desire to give a definite conception to the inner essence of things, and make the real world conceivable as a harmoniously connected intellectual world. This desire of scientific knowledge Aristotle cites expressly as the motive to the Platonic doctrine of ideas. “Plato,” he says (_Metaph._ XIII. 4), “came to the doctrine of ideas because he was convinced of the truth of the Heraclitic view which regarded the sensible world as a ceaseless flowing and changing. His conclusion from this was, that if there be a science of any thing there must be, besides the sensible, other substances which have a permanence, for there can be no science of the fleeting.” It is, therefore, the idea of science which demands the reality of ideas, a demand which cannot be granted unless an idea or conception is also the ground of all being. This is the case with Plato. According to him there can be neither a true knowing nor a true being without ideas and conceptions which have an independent reality.

What now does Plato mean by idea? From what has already been said it is clear that he means something more than ideal conceptions of the beautiful and the good. An idea is found, as the name itself (εἰδος) indicates, wherever a universal conception of a species or kind is found. Hence Plato speaks of the idea of a bed, table, strength, health, voice, color, ideas of simple relations and properties, ideas of mathematical figures, and even ideas of not-being, and of that, which in its essence only contradicts the idea, baseness and vice. In a word, we may put an idea wherever many things may be characterized by a common name (_Rep._ X. 596): or as Aristotle expresses it (_Met._ XII. 3). Plato places an idea to every class of being. In this sense Plato himself speaks in the beginning of the Parmenides. Parmenides asks the young Socrates what he calls ideas. Socrates answers by naming unconditionally the moral ideas, the ideas of the true, the beautiful, the good, and then after a little delay he mentions some physical ones, as the ideas of man, of fire, of water; he will not allow ideas to be predicated of that which is only a formless mass, or which is a part of something else, as hair, mud and clay, but in this he is answered by Parmenides, that if he would be fully imbued with philosophy, he must not consider such things as these to be wholly despicable, but should look upon them as truly though remotely participating in the idea. Here at least the claim is asserted that no province of being is excluded from the idea, that even that which appears most accidental and irrational is yet a part of rational knowledge, in fact that every thing existing may be brought within a rational conception.

5. THE RELATION OF IDEAS TO THE PHENOMENAL WORLD. Analogous to the different definitions of idea are the different names which Plato gives to the sensible and phenomenal world. He calls it the many, the divisible, the unbounded, the undetermined and measureless, the becoming, the relative, great and small, not-being. The relation now in which these two worlds of sense and of ideas stand to each other is a question which Plato has answered neither fully nor consistently with himself. His most common way is to characterize the relation of things to conceptions as a participant, or to call things the copies and adumbrations, while ideas are the archetypes. Yet this is so indefinite that Aristotle properly says that to talk in this way is only to use poetical metaphors. The great difficulty of the doctrine of ideas is not solved but only increased by these figurative representations. The difficulty lies in the contradiction which grows out of the fact that while Plato admits the reality of the becoming and of the province of the becoming, he still affirms that ideas which are substances ever at rest and ever the same are the only actual. Now in this Plato is formally consistent with himself, while he characterizes the _matériel_ of matter not as a positive substratum but as not-being, and guards himself with the express affirmation that he does not consider the sensible as being, but only as something similar to being. (_Rep._ X. 597.) The position laid down in the Parmenides is also consistent with this, that a perfect philosophy should look upon the idea as the cognizable in the phenomenal world, and should follow it out in the smallest particulars until every part of being should be known and all dualism removed. In fine, Plato in many of his expressions seems to regard the world of sensation only as a subjective appearance, as a product of the subjective notion, as the result of a confused way of representing ideas. In this sense the phenomena are entirely dependent on ideas; they are nothing but the ideas themselves in the form of not being; the phenomenal world derives its whole existence from the ideal world which appears in it. But yet when Plato calls the sensible a mingling of the same with the different or the not-being (_Tim._ p. 35), when he characterizes the ideas as vowels which go through every thing like a chain (_Soph._ p. 253), when he himself conceives the possibility that matter might offer opposition to the formative energy of ideas (_Tim._ p. 56), when he speaks of an evil soul of the world (_de Leg._ X. 896), and gives intimations of the presence in the world of a principle in nature hostile to God (_Polit._ p. 268), when he in the Phædon treats of the relation between body and soul as one wholly discordant and malignant,—in all this there is evidence enough, even after allowing for the mythical form of the Timæus, and the rhetorical composition which prevails in the Phædon, to substantiate the contradiction mentioned above. This is most clear in the Timæus. Plato in this dialogue makes the sensible world to be formed by a Creator after the pattern of an idea, but in this he lays down as a condition that this Demi-urge or Creator should find at hand a something which should be apt to receive and exhibit this ideal image. This something Plato compares to the matter which is fashioned by the artisan (whence the later name _hyle_). He characterizes it as wholly undetermined and formless, but possessing in itself an aptitude for every variety of forms, an invisible and shapeless thing, a something which it is difficult to characterize, and which Plato even does not seem inclined very closely to describe. In this the actuality of matter is denied; while Plato makes it equivalent to space it is only the place, the negative condition of the sensible while it possesses a being only as it receives in itself the ideal form. Still matter remains the objective and phenomenal form of the idea: the visible world arises only through the mingling of ideas with this substratum, and if matter be metaphysically expressed as “the different,” then does it follow with logical necessity in a dialectical discussion that it is just as truly being as not-being. Plato does not conceal from himself this difficulty, and therefore attempts to represent with comparisons and images this presupposition of a _hyle_ which he finds it as impossible to do without as to express in a conceivable form. If he would do without it he must rise to the conception of an absolute creation, or consider matter as an ultimate emanation from the absolute spirit, or else explain it as appearance only. Thus the Platonic system is only a fruitless struggle against dualism.

6. THE IDEA OF THE GOOD AND THE DEITY. If the true and the real is exhibited in general conceptions which are so related to each other that every higher conception embraces and combines under it several lower, so that any one starting from a single idea may eventually discover all (_Meno._ p. 81), then must the sum of ideas form a connected organism and succession in which the lower idea appears as a stepping-stone and presupposition to a higher. This succession must have its end in an idea which needs no higher idea or presupposition to sustain it. This highest idea, the ultimate limit of all knowledge, and itself the independent ground of all other ideas, Plato calls the idea of the good, _i. e._ not of the moral but of the metaphysical good. (_Rep._ VII. 517.)

What this good is in itself, Plato undertakes to show only in images. “In the same manner as the sun,” he says in the Republic (VI. 506), “is the cause of sight, and the cause not merely that objects are visible but also that they grow and are produced, so the good is of such power and beauty, that it is not merely the cause of science to the soul, but is also the cause of being and reality to whatever is the object of science, and as the sun is not itself sight or the object of sight but presides over both, so the good is not science and truth but is superior to both, they being not the good itself but of a goodly nature.” The good has unconditioned worth, and gives to every other thing all the value it possesses. The idea of the good excludes all presupposition. It is the ultimate ground at the same time of knowing and of being, of the perceiver and the perceived, of the subjective and the objective, of the ideal and the real, though exalted itself above such a division. (_Rep._ VI. 508-517.) Plato, however, has not attempted a derivation of the remaining ideas from the idea of the good; his course here is wholly an empirical one; a certain class of objects are taken, and having referred these to their common essence this is given out as their idea. He has treated the individual conceptions so independently, and has made each one so complete in itself, that it is impossible to find a proper division or establish an immanent continuation of one into another.

It is difficult to say precisely what relation this idea of the good bore to the Deity in the Platonic view. Taking every thing together it seems clear that Plato regarded the two as identical, but whether he conceived this highest cause to be a personal being or not is a question which hardly admits of a definite answer. The logical result of his system would exclude the personality of God. If only the universal (the idea) is the true being, then can the only absolute idea, the Deity, be only the absolute universal; but that Plato was himself conscious of this logical conclusion we can hardly affirm, any more than we can say on the other hand that he was clearly a theist. For whenever in a mythical or popular statement he speaks of innumerable gods, this only indicates that he is speaking in the language of the popular religion, and when he speaks in an accurate philosophical sense, he only makes the relation of the personal deity with the idea a very uncertain one. Most probable, therefore, is it that this whole question concerning the personality of God was not yet definitely before him, that he took up the religious idea of God and defended it in ethical interest against the anthropomorphism of the mythic poets, that he sought to establish it by arguments drawn from the evidences of design in nature, and the universal prevalence of a belief in a God, while as a philosopher he made no use of it.

V. THE PLATONIC PHYSICS. 1. NATURE.—The connection between the Physics and the Dialectics of Plato lies principally in two points—the conception of becoming, which forms the chief property of nature, and that of real being, which is at once the all sufficient and good, and the true end of all becoming. Because nature belongs to the province of irrational sensation we cannot look for the same accuracy in the treatment of it, as is furnished in dialectics. Plato therefore applied himself with much less zest to physical investigations than to those of an ethical or dialectical character, and indeed only attended to them in his later years. Only in one dialogue, the Timæus, do we find any extended evolution of physical doctrines, and even here Plato seems to have gone to his work with much less independence than his wont, this dialogue being more strongly tinctured with Pythagoreanism than any other of his writings. The difficulty of the Timæus is increased by the mythical form on which the old commentators themselves have stumbled. If we take the first impression that it gives us, we have, before the creation of the world, a Creator as a moving and a reflecting principle, with on the one side the ideal world existing immovable as the eternal archetype, and on the other side, a chaotic, formless, irregular, fluctuating mass, which holds in itself the germ of the material world, but has no determined character nor substance. With these two elements the Creator now blends the world-soul which he distributes according to the relation of numbers, and sets it in definite and harmonious motion. In this way the material world, which has become actual through the arrangement of the chaotic mass into the four elements, finds its external frame, and the process thus begun is completed in its external structure by the formation of the organic world.

It is difficult to separate the mythical and the philosophical elements in this cosmogony of the Timæus, especially difficult to determine how far the historical construction, which gives a succession in time to the acts of creation, is only a formal one, and also how far the affirmation that matter is absolutely a not-being can be harmonized with the general tenor of Plato’s statements. The significance of the world-soul is clearer. Since the soul in the Platonic system is the mean between spirit and body, and as in the same way mathematical relations, in their most universal expression as numbers, are the mean between mere sensuous existence and the pure idea (between the one and the many as Plato expresses it), it would seem clear that the world-soul, construed according to the relation of numbers, must express the relation of the world of ideas to that of sense, in other words, that it denotes the sensible world as a thought represented in the form of material existence. The Platonic view of nature, in opposition to the mechanical attempts to explain it of the earlier philosophers, is entirely teleological, and based upon the conception of the good, or, on the moral idea. Plato conceives the world as the image of the good, as the work of the divine munificence. As it is the image of the perfect it is therefore only one, corresponding to the idea of the single all-embracing substance, for an infinite number of worlds is not to be conceived as actual. For the same reason the world is spherical, after the most perfect and uniform structure, which embraces in itself all other forms; its movement is in a circle, because this, by returning into itself, is most like the movement of reason. The particular points of the Timæus, the derivation of the four elements, the separation of the seven planets according to the musical scale, the opinion that the stars were immortal and heavenly substances, the affirmation that the earth holds an abiding position in the middle of the world, a view which subsequently became elaborated to the Ptolemaic system, the reference of all material figures to the triangle as the simplest plane figure, the division of inanimate nature, according to the four elements, into creatures of earth, water, and air, his discussions respecting organic nature, and especially respecting the construction of the human body—all these we need here only mention. Their philosophical worth consists not so much in their material content, but rather in their fundamental idea, that the world should be conceived as the image and the work of reason, as an organism of order, harmony, and beauty, as the good actualizing itself.

2. THE SOUL.—The doctrine of the soul, considering it simply as the basis of a moral action, and leaving out of view all questions of concrete ethics, forms a constituent element in the Platonic physics. Since the soul is united to the body, it participates in the motions and changes of the body, and is, in this respect, related to the perishable. But in so far as it participates in the knowledge of the eternal, _i. e._ in so far as it knows ideas, does there live within it a divine principle—reason. Accordingly, Plato distinguishes two components of the soul—the divine and the mortal, the rational and the irrational. These two are united by an intermediate link, which Plato calls θυμὸς or spirit, and which, though allied to reason is not reason itself, since it is often exhibited in children and also in brutes, and since even men are often carried away by it without reflection. This threefoldness, here exhibited psychologically, is found, in different applications, through all the last general period of Plato’s literary life. Based upon the anthropological triplicate of reason, soul and body, it corresponds also to the division of theoretical knowledge into science (or thinking), correct opinions (or sense-perception), and ignorance, to the triple ladder of eroticism in the Symposium and the mythological representation connected with this of Poros, Eros, and Penia; to the metaphysical triplicate of the ideal world, mathematical relations and the sensible world; and furnishes ground for deriving the ethical division of virtue and the political division of ranks.