Chapter XII
.
V. We should expect to find, as was insisted on in the preceding section in reference to the sterility of hybrids, that it required many, or at any rate several, generations of changed habits before a sufficiently deep impression could be made upon the living being (who must be regarded always as one person in his whole line of ascent or descent) for it to be unconsciously remembered by him, when making himself anew in any succeeding generation, and thus to make him modify his method of procedure during his next embryological development. Nevertheless, we should expect to find that sometimes a very deep single impression made upon a living organism, should be remembered by it, even when it is next in an embryonic condition.
That this is so, we find from Mr. Darwin, who writes (“Plants and Animals under Domestication,” vol. ii. p. 57, ed. 1875)—“There is ample evidence that the effect of mutilations and of accidents, especially, or perhaps exclusively, when followed by disease” (which would certainly intensify the impression made), “are occasionally inherited. There can be no doubt that the evil effects of the long continued exposure of the parent to injurious conditions are sometimes transmitted to the offspring.” As regards impressions of a less striking character, it is so universally admitted that they are not observed to be repeated in what is called the offspring, until they have been confirmed in what is called the parent, for several generations, but that after several generations, more or fewer as the case may be, they often are transmitted—that it seems unnecessary to say more upon the matter. Perhaps, however, the following passage from Mr. Darwin may be admitted as conclusive:—
“That they” (acquired actions) “are inherited, we see with horses in certain transmitted paces, such as cantering and ambling, which are not natural to them—in the pointing of young pointers, and the setting of young setters—in the peculiar manner of flight of certain breeds of the pigeon, &c. We have analogous cases with mankind in the inheritance of tricks or unusual gestures.” . . . (“Expression of the Emotions,” p. 29).
In another place Mr. Darwin writes:—
“How again can we explain _the inherited effects_ of the use or disuse of
## particular organs? The domesticated duck flies less and walks more than
the wild duck, and its limb bones have become diminished and increased in a corresponding manner in comparison with those of the wild duck. A horse is trained to certain paces, and the colt inherits similar consensual movements. The domesticated rabbit becomes tame from close confinement; the dog intelligent from associating with man; the retriever is taught to fetch and carry; and these mental endowments and bodily powers are all inherited” (“Plants and Animals,” &c., vol. ii. p. 367, ed. 1875).
“Nothing,” he continues, “in the whole circuit of physiology is more wonderful. How can the use or disuse of a particular limb, or of the brain, affect a small aggregate of reproductive cells, seated in a distant part of the body in such a manner that the being developed from these cells inherits the character of one or both parents? Even an imperfect answer to this question would be satisfactory” (“Plants and Animals,” &c. vol. ii. p. 367, ed. 1875).
With such an imperfect answer will I attempt to satisfy the reader, as to say that there appears to be that kind of continuity of existence and sameness of personality, between parents and offspring, which would lead us to expect that the impressions made upon the parent should be epitomised in the offspring, when they have been or have become important enough, through repetition in the history of several so-called existences to have earned a place in that smaller edition, which is issued from generation to generation; or, in other words, when they have been made so deeply, either at one blow or through many, that the offspring can remember them. In practice we observe this to be the case—so that the answer lies in the assertion that offspring and parent, being in one sense but the same individual, there is no great wonder that, in one sense, the first should remember what had happened to the latter; and that too, much in the same way as the individual remembers the events in the earlier history of what he calls his own lifetime, but condensed, and pruned of detail, and remembered as by one who has had a host of other matters to attend to in the interim.
It is thus easy to understand why such a rite as circumcision, though practised during many ages, should have produced little, if any, modification tending to make circumcision unnecessary. On the view here supported such modification would be more surprising than not, for unless the impression made upon the parent was of a grave character—and probably unless also aggravated by subsequent confusion of memories in the cells surrounding the part originally impressed—the parent himself would not be sufficiently impressed to prevent him from reproducing himself, as he had already done upon an infinite number of past occasions. The child, therefore, in the womb would do what the father in the womb had done before him, nor should any trace of memory concerning circumcision be expected till the eighth day after birth, when, but for the fact that the impression in this case is forgotten almost as soon as made, some slight presentiment of coming discomfort might, after a large number of generations, perhaps be looked for as a general rule. It would not, however, be surprising, that the effect of circumcision should be occasionally inherited, and it would appear as though this was sometimes actually the case.
The question should turn upon whether the disuse of an organ has arisen:—
1. From an internal desire on the part of the creature disusing it, to be quit of an organ which it finds troublesome.
2. From changed conditions and habits which render the organ no longer necessary, or which lead the creature to lay greater stress on certain other organs or modifications.
3. From the wish of others outside itself; the effect produced in this case being perhaps neither very good nor very bad for the individual, and resulting in no grave impression upon the organism as a whole.
4. From a single deep impression on a parent, affecting both himself as a whole, and gravely confusing the memories of the cells to be reproduced, or his memories in respect of those cells—according as one adopts Pangenesis and supposes a memory to “run” each gemmule, or as one supposes one memory to “run” the whole impregnate ovum—a compromise between these two views being nevertheless perhaps possible, inasmuch as the combined memories of all the cells may possibly _be_ the memory which “runs” the impregnate ovum, just as we _are_ ourselves the combination of all our cells, each one of which is both autonomous, and also takes its share in the central government. But within the limits of this volume it is absolutely impossible for me to go into this question.
In the first case—under which some instances which belong more strictly to the fourth would sometimes, but rarely, come—the organ should soon go, and sooner or later leave no rudiment, though still perhaps to be found crossing the life of the embryo, and then disappearing.
In the second it should go more slowly, and leave, it may be, a rudimentary structure.
In the third it should show little or no sign of natural decrease for a very long time.
In the fourth there may be absolute and total sterility, or sterility in regard to the particular organ, or a scar which shall show that the memory of the wound and of each step in the process of healing has been remembered; or there may be simply such disturbance in the reproduced organ as shall show a confused recollection of injury. There may be infinite gradations between the first and last of these possibilities.
I think that the facts, as given by Mr. Darwin (“Plants and Animals,” &c., vol. i. pp. 466–472, ed. 1875), will bear out the above to the satisfaction of the reader. I can, however, only quote the following passage:—
“ . . . Brown Séquard has bred during thirty years many thousand guinea-pigs, . . . nor has he ever seen a guinea-pig born without toes which was not the offspring of parents _which had gnawed off their own toes_, owing to the sciatic nerve having been divided. Of this fact thirteen instances were carefully recorded, and a greater number were seen; yet Brown Séquard speaks of such cases as among the rarer forms of inheritance. It is a still more interesting fact—‘that the sciatic nerve in the congenitally toeless animal has inherited the power of passing through _all the different morbid states_ which have occurred in one of its parents _from the time of division_ till after its reunion with the peripheric end. It is not therefore the power of simply performing an
## action which is inherited, but the power of performing a whole series of
## actions in a certain order.’”
I feel inclined to say it is not merely the original wound that is remembered, but the whole process of cure which is now accordingly repeated. Brown Séquard concludes, as Mr. Darwin tells us, “that what is transmitted is the morbid state of the nervous system,” due to the operation performed on the parents.
A little lower down Mr. Darwin writes that Professor Rolleston has given him two cases—“namely, of two men, one of whom had his knee, and the other his cheek, severely cut, and both had children born with exactly the same spot marked or scarred.”
VI. When, however, an impression has once reached transmission point—whether it be of the nature of a sudden striking thought, which makes its mark deeply then and there, or whether it be the result of smaller impressions repeated until the nail, so to speak, has been driven home—we should expect that it should be remembered by the offspring as something which he has done all his life, and which he has therefore no longer any occasion to learn; he will act, therefore, as people say, _instinctively_. No matter how complex and difficult the process, if the parents have done it sufficiently often (that is to say, for a sufficient number of generations), the offspring will remember the fact when association wakens the memory; it will need no instruction, and—unless when it has been taught to look for it during many generations—will expect none. This may be seen in the case of the humming-bird sphinx moth, which, as Mr. Darwin writes, “shortly after its emergence from the cocoon, as shown by the bloom on its unruffled scales, may be seen poised stationary in the air with its long hair-like proboscis uncurled, and inserted into the minute orifices of flowers; _and no one I believe has ever seen_ this moth learning to perform its difficult task, which requires such unerring aim” (“Expression of the Emotions,” p. 30).
And, indeed, when we consider that after a time the most complex and difficult actions come to be performed by man without the least effort or consciousness—that offspring cannot be considered as anything but a continuation of the parent life, whose past habits and experiences it epitomises when they have been sufficiently often repeated to produce a lasting impression—that consciousness of memory vanishes on the memory’s becoming intense, as completely as the consciousness of complex and difficult movements vanishes as soon as they have been sufficiently practised—and finally, that the real presence of memory is testified rather by performance of the repeated action on recurrence of like surroundings, than by consciousness of recollecting on the part of the individual—so that not only should there be no reasonable bar to our attributing the whole range of the more complex instinctive actions, from first to last, to memory pure and simple, no matter how marvellous they may be, but rather that there is so much to compel us to do so, that we find it difficult to conceive how any other view can have been ever taken—when, I say, we consider all these facts, we should rather feel surprise that the hawk and sparrow still teach their offspring to fly, than that the humming-bird sphinx moth should need no teacher.
The phenomena, then, which we observe are exactly those which we should expect to find.
VII. We should also expect that the memory of animals, as regards their earlier existences, was solely stimulated by association. For we find, from Prof. Bain, that “actions, sensations, and states of feeling occurring together, or in close succession, tend to grow together or cohere in such a way that when any one of them is afterwards presented to the mind, the others are apt to be brought up in idea” (“The Senses and the Intellect,” 2d ed. 1864, p. 332). And Prof. Huxley says (“Elementary Lessons in Physiology,” 5th ed. 1872, p. 306), “It may be laid down as a rule that if any two mental states be called up together, or in succession, with due frequency and vividness, the subsequent production of the one of them will suffice to call up the other, _and that whether we desire it or not_.” I would go one step further, and would say not only whether we desire it or not, but _whether we are aware that the idea has ever before been called up in our minds or not_. I should say that I have quoted both the above passages from Mr. Darwin’s “Expression of the Emotions” (p. 30, ed. 1872).
We should, therefore, expect that when the offspring found itself in the presence of objects which had called up such and such ideas for a sufficient number of generations, that is to say, “with due frequency and vividness”—it being of the same age as its parents were, and generally in like case as when the ideas were called up in the minds of the parents—the same ideas should also be called up in the minds of the offspring “_whether they desire it or not_;” and, I would say also, “whether they recognise the ideas as having ever before been present to them or not.”
I think we might also expect that no other force, save that of association, should have power to kindle, so to speak, into the flame of
## action the atomic spark of memory, which we can alone suppose to be
transmitted from one generation to another.
That both plants and animals do as we should expect of them in this respect is plain, not only from the performance of the most intricate and difficult actions—difficult both physically and intellectually—at an age, and under circumstances which preclude all possibility of what we call instruction, but from the fact that deviations from the parental instinct, or rather the recurrence of a memory, unless in connection with the accustomed train of associations, is of comparatively rare occurrence; the result, commonly, of some one of the many memories about which we know no more than we do of the memory which enables a cat to find her way home after a hundred-mile journey by train, and shut up in a hamper, or, perhaps even more commonly, of abnormal treatment.
VIII. If, then, memory depends on association, we should expect two corresponding phenomena in the case of plants and animals—namely, that they should show a tendency to resume feral habits on being turned wild after several generations of domestication, and also that peculiarities should tend to show themselves at a corresponding age in the offspring and in the parents. As regards the tendency to resume feral habits, Mr. Darwin, though apparently of opinion that the tendency to do this has been much exaggerated, yet does not doubt that such a tendency exists, as shown by well authenticated instances. He writes: “It has been repeatedly asserted in the most positive manner by various authors that feral animals and plants invariably return to their primitive specific type.”
This shows, at any rate, that there is a considerable opinion to this effect among observers generally.
He continues: “It is curious on what little evidence this belief rests. Many of our domesticated animals could not subsist in a wild state,”—so that there is no knowing whether they would or would not revert. “In several cases we do not know the aboriginal parent species, and cannot tell whether or not there has been any close degree of reversion.” So that here, too, there is at any rate no evidence _against_ the tendency; the conclusion, however, is that, notwithstanding the deficiency of positive evidence to warrant the general belief as to the force of the tendency, yet “the simple fact of animals and plants becoming feral does cause some tendency to revert to the primitive state,” and he tells us that “when variously-coloured tame rabbits are turned out in Europe, they generally re-acquire the colouring of the wild animal;” “there can be no doubt,” he says, “that this really does occur,” though he seems inclined to account for it by the fact that oddly-coloured and conspicuous animals would suffer much from beasts of prey and from being easily shot. “The best known case of reversion:” he continues, “and that on which the widely-spread belief in its universality apparently rests, is that of pigs. These animals have run wild in the West Indies, South America, and the Falkland Islands, and have everywhere re-acquired the dark colour, the thick bristles, and great tusks of the wild boar; and the young have re-acquired longitudinal stripes.” And on page 22 of “Plants and Animals under Domestication” (vol. ii. ed. 1875) we find that “the re-appearance of coloured, longitudinal stripes on young feral pigs cannot be attributed to the direct action of external conditions. In this case, and in many others, we can only say that any change in the habits of life apparently favours a tendency, inherent or latent, in the species to return to the primitive state.” On which one cannot but remark that though any change may favour such tendency, yet the return to original habits and surroundings appears to do so in a way so marked as not to be readily referable to any other cause than that of association and memory—the creature, in fact, having got into its old groove, remembers it, and takes to all its old ways.
As regards the tendency to inherit changes (whether embryonic, or during post-natal development as ordinarily observed in any species), or peculiarities of habit or form which do not partake of the nature of disease, it must be sufficient to refer the reader to Mr. Darwin’s remarks upon this subject (“Plants and Animals Under Domestication,” vol. ii. pp. 51–57, ed. 1875). The existence of the tendency is not likely to be denied. The instances given by Mr. Darwin are strictly to the point as regards all ordinary developmental and metamorphic changes, and even as regards transmitted acquired actions, and tricks acquired before the time when the offspring has issued from the body of the parent, or on an average of many generations does so; but it cannot for a moment be supposed that the offspring knows by inheritance anything about what happens to the parent subsequently to the offspring’s being born. Hence the appearance of diseases in the offspring, at comparatively late periods in life, but at the same age as, or earlier, than in the parents, must be regarded as due to the fact that in each case the machine having been made after the same pattern (which _is_ due to memory), is liable to have the same weak points, and to break down after a similar amount of wear and tear; but after less wear and tear in the case of the offspring than in that of the parent, because a diseased organism is commonly a deteriorating organism, and if repeated at all closely, and without repentance and amendment of life, will be repeated for the worse. If we do not improve, we grow worse. This, at least, is what we observe daily.
Nor again can we believe, as some have fancifully imagined, that the remembrance of any occurrence of which the effect has been entirely, or almost entirely mental, should be remembered by offspring with any definiteness. The intellect of the offspring might be affected, for better or worse, by the general nature of the intellectual employment of the parent; or a great shock to a parent might destroy or weaken the intellect of the offspring; but unless a deep impression were made upon the cells of the body, and deepened by subsequent disease, we could not expect it to be remembered with any definiteness, or precision. We may talk as we will about mental pain, and mental scars, but after all, the impressions they leave are incomparably less durable than those made by an organic lesion. It is probable, therefore, that the feeling which so many have described, as though they remembered this or that in some past existence, is purely imaginary, and due rather to unconscious recognition of the fact that we certainly have lived before, than to any actual occurrence corresponding to the supposed recollection.
And lastly, we should look to find in the action of memory, as between one generation and another, a reflection of the many anomalies and exceptions to ordinary rules which we observe in memory, so far as we can watch its action in what we call our own single lives, and the single lives of others. We should expect that reversion should be frequently capricious—that is to say, give us more trouble to account for than we are either able or willing to take. And assuredly we find it so in fact. Mr. Darwin—from whom it is impossible to quote too much or too fully, inasmuch as no one else can furnish such a store of facts, so well arranged, and so above all suspicion of either carelessness or want of candour—so that, however we may differ from him, it is he himself who shows us how to do so, and whose pupils we all are—Mr. Darwin writes: “In every living being we may rest assured that a host of long-lost characters lie ready to be evolved under proper conditions” (does not one almost long to substitute the word “memories” for the word “characters?”) “How can we make intelligible, and connect with other facts, this wonderful and common capacity of reversion—this power of calling back to life long-lost characters?” (“Plants and Animals,” &c., vol. ii. p. 369, ed. 1875). Surely the answer may be hazarded, that we shall be able to do so when we can make intelligible the power of calling back to life long-lost memories. But I grant that this answer holds out no immediate prospect of a clear understanding.
One word more. Abundant facts are to be found which point inevitably, as will appear more plainly in the following chapter, in the direction of thinking that offspring inherits the memories of its parents; but I know of no single fact which suggests that parents are in the smallest degree affected (other than sympathetically) by the memories of their offspring _after that offspring has been born_. Whether the unborn offspring affects the memory of the mother in some particulars, and whether we have here the explanation of occasional reversion to a previous impregnation, is a matter on which I should hardly like to express an opinion now. Nor, again, can I find a single fact which seems to indicate any memory of the parental life on the part of offspring later than the average date of the offspring’s quitting the body of the parent.
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