Chapter III: Part 3

The next point which I shall mention, in illustration of the extremely close resemblance between certain twins, is the similarity in the association of their ideas. No less than eleven out of the thirty-five cases testify to this. They make the same remarks on the same occasion, begin singing the same song at the same moment, and so on; or one would commence a sentence, and the other would finish it. An observant friend graphically described to me the effect produced on her by two such twins whom she had met casually. She said: "Their teeth grew alike, they spoke alike and together, and said the same things, and seemed just like one person." One of the most curious anecdotes that I have received concerning this similarity of ideas was that one twin A, who happened to be at a town in Scotland, bought a set of champagne glasses which caught his attention, as a surprise for his brother B; while at the same time, B, being in England, bought a similar set of precisely the same pattern as a surprise for A. Other anecdotes of a like kind have reached me about these twins.

The last point to which I shall allude regards the tastes and dispositions of the thirty-five pairs of twins. In sixteen cases--that is, in nearly one half of them--these were described as closely similar; in the remaining nineteen they were much alike, but subject to certain named differences. These differences belonged almost wholly to such groups of qualities as these: The one was the more vigorous, fearless, energetic; the other was gentle, clinging, and timid: or, again, the one was more ardent, the other more calm and gentle; or again, the one was the more independent, original, and self-contained; the other the more generous, hasty, and vivacious. In short the difference was always that of intensity or energy in one or other of its protean forms: it did not extend more deeply into the structure of the characters. The more vivacious might be subdued by ill health, until he assumed the character of the other; or the latter might be raised by excellent health to that of the former. The difference is in the key-note, not in the melody.

It follows from what has been said concerning the similar dispositions of the twins, the similarity in the associations of their ideas, of their special ailments, and of their illnesses generally, that the resemblances are not superficial, but extremely intimate. I have only two cases altogether of a strong bodily resemblance being accompanied by mental diversity, and one case only of the converse kind. It must be remembered that the conditions which govern extreme likeness between twins are not the same as those between ordinary brothers and sisters (I may have hereafter to write further about this); and that it would be wholly incorrect to generalize from what has just been said about the twins, that mental and bodily likeness are invariably co-ordinate; such being by no means the case.

We are now in a position to understand that the phrase "close similarity" is no exaggeration, and to realize the value of the evidence about to be adduced. Here are thirty-five cases of twins who were "closely alike" in body and mind when they were young, and who have been reared exactly alike up to their early manhood and womanhood. Since then the conditions of their lives have changed; what change of conditions has produced the most variation?

It was with no little interest that I searched the records of the thirty-five cases for an answer; and they gave an answer that was not altogether direct, but it was very distinct, and not at all what I had expected. They showed me that in some cases the resemblance of body and mind had continued unaltered up to old age, notwithstanding very different conditions of life; and they showed in the other cases that the parents ascribed such dissimilarity as there was wholly, or almost wholly, to some form of illness. In four cases it was scarlet fever; in one case, typhus; in one, a slight effect was ascribed to a nervous fever: then I find effects from an Indian climate; from an illness (unnamed) of nine months' duration; from varicose veins; from a bad fracture of the leg, which prevented all active exercise afterwards; and there were three other cases of ill health. It will be sufficient to quote one of the returns; in this the father writes:

"At birth they were _exactly_ alike, except that one was born with a bad varicose affection, the effect of which had been to prevent any violent exercise, such as dancing, or running, and, as she has grown older, to make her more serious and thoughtful. Had it not been for this infirmity, I think the two would have been as exactly alike as it is possible for two women to be, both mentally and physically; even now they are constantly mistaken for one another."

In only a very few cases is there some allusion to the dissimilarity being partly due to the combined action of many small influences, and in no case is it largely, much less wholly, ascribed to that cause. In not a single instance have I met with a word about the growing dissimilarity being due to the action of the firm, free will of one or both of the twins, which had triumphed over natural tendencies; and yet a large proportion of my correspondents happen to be clergymen whose bent of mind is opposed, as I feel assured from the tone of their letters, to a necessitarian view of life.

It has been remarked that a growing diversity between twins may be ascribed to the tardy development of naturally diverse qualities; but we have a right, upon the evidence I have received, to go further than this. We have seen that a few twins retain their close resemblance through life; in other words, instances do exist of thorough similarity of nature, and in these external circumstances do not create dissimilarity. Therefore, in those cases, where there is a growing diversity, and where no external cause can be assigned either by the twins themselves or by their family for it, we may feel sure that it must be chiefly or altogether due to a want of thorough similarity in their nature. Nay further, in some cases it is distinctly affirmed that the growing dissimilarity can be accounted for in no other way. We may therefore broadly conclude that the only circumstance, within the range of those by which persons of similar conditions of life are affected, capable of producing a marked effect on the character of adults, is illness or some accident which causes physical infirmity. The twins who closely resembled each other in childhood and early youth, and were reared under not very dissimilar conditions, either grow unlike through the development of natural characteristics which had lain dormant at first, or else they continue their lives, keeping time like two watches, hardly to be thrown out of accord except by some physical jar. Nature is far stronger than nurture within the limited range that I have been careful to assign to the latter.

The effect of illness, as shown by these replies, is great, and well deserves further consideration. It appears that the constitution of youth is not so elastic as we are apt to think, but that an attack, say of scarlet fever, leaves a permanent mark, easily to be measured by the present method of comparison. This recalls an impression made strongly on my mind several years ago by the sight of a few curves drawn by a mathematical friend. He took monthly measurements of the circumference of his children's heads during the first few years of their lives, and he laid down the successive measurements on the successive lines of a piece of ruled paper, by taking the edge of the paper as a base. He then joined the free ends of the lines, and so obtained a curve of growth. These curves had, on the whole, that regularity of sweep that might have been expected, but each of them showed occasional halts, like the landing places on a long flight of stairs. The development had been arrested by something, and was not made up for by after growth. Now, on the same piece of paper my friend had also registered the various infantile illnesses of the children, and corresponding to each illness was one of these halts. There remained no doubt in my mind that, if these illnesses had been warped off, the development of the children would have been increased by almost the precise amount lost in these halts. In other words, the disease had drawn largely upon the capital, and not only on the income, of their constitutions. I hope these remarks may induce some men of science to repeat similar experiments on their children of the future. They may compress two years of a child's history on one side of a ruled half-sheet of foolscap paper if they cause each successive line to stand for a successive month, beginning from the birth of the child; and if they mark off the measurements by laying, not the 0-inch division of the tape against the edge of the pages, but, say, the 10-inch division--in order to economize space.

The steady and pitiless march of the hidden weaknesses in our constitutions, through illness to death, is painfully revealed by these histories of twins. We are too apt to look upon illness and death as capricious events, and there are some who ascribe them to the direct effect of supernatural interference, whereas the fact of the maladies of two twins being continually alike, shows that illness and death are necessary incidents in a regular sequence of constitutional changes, beginning at birth, upon which external circumstances have, on the whole, very small effect. In cases where the maladies of the twins are continually alike, the clock of life moves regularly on, governed by internal mechanism. When the hand approaches the hour mark, there is a sudden click, followed by a whirling of wheels; at the culminating moment, the stroke falls. Necessitarians may derive new arguments from the life histories of twins.

We will now consider the converse side of our subject. Hitherto we have investigated cases where the similarity at first was close, but afterwards became less: now we will examine those in which there was great dissimilarity at first, and will see how far an identity of nurture in childhood and youth tended to assimilate them. As has been already mentioned, there is a large proportion of cases of sharply contrasted characteristics, both of body and mind, among twins. I have twenty such cases, given with much detail. It is a fact, that extreme dissimilarity, such as existed between Esau and Jacob, is a no less marked peculiarity in twins of the same sex, than extreme similarity. On this curious point, and on much else in the history of twins, I have many remarks to make, but this is not the place to make them.

The evidence given by the twenty cases above mentioned is absolutely accordant, so that the character of the whole may be exactly conveyed by two or three quotations. One parent says: "They have had _exactly the same nurture_ from their birth up to the present time; they are both perfectly healthy and strong, yet they are otherwise as dissimilar as two boys could be, physically, mentally, and in their emotional nature." Here is another case: "I can answer most decidedly that the twins have been perfectly dissimilar in character, habits, and likeness from the moment of their birth to the present time, though they were nursed by the same woman, went to school together, and were never separated till the age of fifteen." Here again is one more, in which the father remarks: "They were curiously different in body and mind from their birth." The surviving twin (a senior wrangler of Cambridge) adds: "A fact struck all our school contemporaries, that my brother and I were complementary, so to speak, in point of ability and disposition. He was contemplative, poetical, and literary to a remarkable degree, showing great power in that line. I was practical, mathematical, and linguistic. Between us we should have made a very decent sort of a man." I could quote others just as strong as these, while I have not a single case in which my correspondents speak of originally dissimilar characters having become assimilated through identity of nurture. The impression that all this evidence leaves on the mind is one of some wonder whether nurture can do anything at all beyond giving instruction and professional training. It emphatically corroborates and goes far beyond the conclusions to which we had already been driven by the cases of similarity. In these, the causes of divergence began to act about the period of adult life, when the characters had become somewhat fixed; but here the causes conducive to assimilation began to act from the earliest moment of the existence of the twins, when the disposition was most pliant, and they were continuous until the period of adult life. There is no escape from the conclusion that nature prevails enormously over nurture when the differences of nurture do not exceed what is commonly to be found among persons of the same rank of society and in the same country. My only fear is that my evidence seems to prove too much and may be discredited on that account, as it seems contrary to all experience that nurture should go for little. But experience is often fallacious in ascribing great effects to trifling circumstances. Many a person has amused himself with throwing bits of stick into a tiny brook and watching their progress; how they are arrested, first by one chance obstacle, then by another; and again, how their onward course is facilitated by a combination of circumstances. He might ascribe much importance to each of these events, and think how largely the destiny of the stick has been governed by a series of trifling accidents. Nevertheless all the sticks succeed in passing down the current, and they travel, in the long run, at nearly the same rate. So it is with life in respect to the several accidents which seem to have had a great effect upon our careers. The one element, which varies in different individuals, but is constant in each of them, is the natural tendency; it corresponds to the current in the stream, and invariably asserts itself. More might be added on this matter, and much might be said in qualification of the broad conclusions to which we have arrived, as to the points in which education appears to create the most permanent effect; how far by training the intellect and how far by subjecting the boy to a higher or lower tone of public opinion; but this is foreign to my immediate object. The latter has been to show broadly, and, I trust, convincingly, that statistical estimation of natural gifts by a comparison of successes in life, is not open to the objection stated at the beginning of this memoir. We have only to take reasonable care in selecting our statistics, and then we may safely ignore the many small differences in nurture which are sure to have characterized each individual case.

SIGHT IN SAVAGES

From "Idle Days in Patagonia"

WILLIAM HENRY HUDSON

[William Henry Hudson was born and for many years resided in
Patagonia. His "The Naturalist in La Plata" and "Idle Days in
Patagonia," both published by J. M. Dent & Co., London, and
D. Appleton & Co., New York, are among the most delightful
books of natural history ever written.]

A person much given to card-playing once informed me that always after the first few rounds of a game he knew some of the cards in the pack, and could recognize them as they were being dealt out, by means of certain slight shades of difference in the colouring of the backs. He had turned his attention to this business when very young, and as he was close upon fifty when he imparted this interesting piece of information, and had always existed comfortably on his winnings, I saw no reason to disbelieve what he told me. Yet this very man, whose vision was keen enough to detect differences in cards so slight that another could not see them, even when pointed out--this preternaturally sharp-eyed individual was greatly surprised when I explained to him that half a dozen birds of the sparrow kind, that fed in his courtyard, and sang and built their nests in his garden and vineyard and fields, were not one but six distinct species. He had never seen any difference in them: they all had the same customs, the same motions; in size, colour, and shape they were all one; to his hearing they all chirped and twittered alike, and warbled the same song.

And as it was with this man, so, to some extent, it is with all of us. That special thing which interests us, and in which we find our profit or pleasure, we see very distinctly, and our memories are singularly tenacious of its image; while other things, in which we take only a general interest, or which are nothing to us, are not seen so sharply, and soon become blurred in memory; and if there happens to be a pretty close resemblance in several of them, as in the case of my gambling friend's half a dozen sparrows, which, like snowflakes, were "seen rather than distinguished," this indistinctness of their images on the eye and the mind causes them all to appear alike. We have, as it were, two visions--one to which all objects appear vividly and close to us, and are permanently photographed on the mind; the other which sees things at a distance, and with that indistinctness of outline and uniformity of colour which distance gives.

In this place I had proposed to draw on my La Plata notebooks for some amusing illustrations of this fact of our two sights; but it is not necessary to go so far afield for illustrations, or to insist on a thing so familiar. "The shepherd knows his sheep," is a saying just as true of this country--of Scotland, at all events--as of the far East. Detectives, also military men who take an interest in their profession, see faces more sharply than most people, and remember them as distinctly as others remember the faces of a very limited number of individuals--of those they love or fear or constantly associate with. Sailors see atmospheric changes which are not apparent to others; and, in like manner, the physician detects the signs of malady in faces which to the uninstructed vision seem healthy enough. And so on through the whole range of professions and pursuits which men have: each person inhabits a little world of his own, as it were, which to others is only part of the distant general blueness obscuring all things, but in which, to him, every object stands out with wonderful clearness, and plainly tells its story.

All this may sound very trite, very trivial and matter of common knowledge--so common as to be known to every schoolboy and to the boy that goeth not to school; yet it is because this simple familiar fact has been ignored, or has not always been borne in mind by our masters, that they have taught us an error, namely, that savages are our superiors in visual power, and that the difference is so great that ours is a dim decaying sense compared with their brilliant faculty, and that only when we survey the prospect through powerful field-glasses do we rise to their level and see the world as they see it. The truth is that the savage sight is no better than ours, although it might seem natural enough to think the contrary, on account of their simple natural life in the desert, which is always green and restful to the eye, or supposed to be so; and because they have no gas nor even candlelight to irritate the visual nerve, and do themselves no injury by poring over miserable books.

Possibly, then, the beginning of the error was in this preconceived notion, that greenness and the absence of artificial light, with other conditions of a primitive life, kept the sight from deteriorating. The eye's adaptiveness did not get sufficient credit. We know how the muscles may be developed by training, that the blacksmith and prizefighter have mightier arms than others; but it was perhaps assumed that the complex structure and extreme delicacy of the eye would make it less adaptive than other and coarser organs. Whatever the origin of the error may have been, it is certain that it has received the approval of scientists, and that they never open their lips on the subject except to give it fresh confirmation. Their researches have brought to light a great variety of eye-troubles, which, in many cases, are not troublesome at all, until they are discovered, named with a startling name and described in terms very alarming to persons of timid character. Frequently they are not maladies, but inherited defects, like bandy legs, prominent teeth, crushed toes, tender skin and numberless other malformations. That such eye-defects are as common among savages as among ourselves, I do not say, and to this matter I shall return later on; but until the eyes of savages are scientifically examined, it seems a very bold thing to say that defective colour-sense is due to the inimical conditions of our civilization; for we know as little about the colour-sense of savages as we do about the colour-sense of the old Greeks. That the savage sight is vastly more powerful than ours was perhaps not so bold a thing to say, seeing that in this matter our teachers were misled by travellers' tales, and perhaps by other considerations, as, for instance, the absence of artificial aids to sight among the children of nature. The redskin may be very old, but as he sits sunning himself before his wigwam in the early morning he is never observed to trombone his newspaper.

The reader may spare himself the trouble of smiling, for this is not mere supposition; in this case observation came first and reflection afterwards, for I happen to know something of savages from experience, and when they were using their eyes in their way and for their purposes, I used mine for my purpose, which was different. It is true that the redskin will point you out an object in the distance and tell its character, and it will be to your sight only a dark-coloured object, which might be a bush, or stone, or animal of some large kind, or even a house. The secret of the difference is that his eye is trained and accustomed to see certain things, which he looks for and expects to find. Put him where the conditions are new to him and he will be at fault; or even on his native heath, set before him an unfamiliar or unexpected object, and he will show no superiority over his civilized brother. I have witnessed one instance in which not one but five men were all at fault and made a wrong guess; while the one person of our party who guessed correctly, or saw better perhaps, was a child of civilization and a reader of books, and, what is perhaps even more, the descendant of a long line of bookish men. This amazed me at the moment, for until then my childlike faith in the ideas of Humboldt and of the world generally on the subject had never been disturbed. Now I see how this curious thing happened. The object was at such a distance that to all of us alike it presented no definite form, but was merely something dark, standing against a hoary background of tall grass-plumes. Our guides, principally regarding its size, at once guessed it to be an animal which they no doubt expected to find in that place--namely, a wild horse. The other, who did not have that training of the eye and mind for distant objects in the desert which is like an instinct, and, like instinct, is liable to mistakes, and who carefully studied its appearance for himself, pronounced it to be a dark bush. When we got near it turned out to be a clump of tall bulrushes, growing in a place where they had no business to grow, and burnt by drought and frosts to so dark a brown that at a distance they seemed quite black.

In the following case the savage was right. I pointed out an object, dark, far off, so low down as to be just visible above the tall grasses, passing with a falling and rising motion like that of a horseman going at a swinging gallop. "There goes a mounted man," I remarked. "No--a traru," returned my companion, after one swift glance; the traru being a large, black, eagle-like bird of the plains. But the object was not necessarily more distinct to him than to me; he could not see wings and beak at that distance; but the traru was a familiar object, which he was accustomed to see at all distances--a figure in the landscape which he looked for and expected to find. It was only a dark blot on the horizon; but he knew the animal's habits and appearance, and that when seen far off, in its low down, dilatory rising and falling flight, it simulates the appearance of a horseman in full gallop. To know this and a few other things was his vocation. If one had set him to find a reversed little _s_ in the middle of a closely-printed page the tears would have run down his bronzed cheeks, and he would have abandoned the vain quest with aching eyeballs. Yet the proofreader can find the little _s_ in a few moments, without straining his sight. But it is infinitely more important to the savage than to us to see things quickly and guess their nature correctly. His daily food, the recovery of his lost animals and his personal safety depend on it; and it is not, therefore, strange that every blot of dark colour, every moving and motionless object on the horizon tells its story better to him than to a stranger; especially when we consider how small a variety of objects he is called on to see and judge of in the level monotonous region he inhabits.

This quick judging of dimly seen distant things, the eye and mind achievement of the mounted barbarian on the unobstructed plains, is not nearly so admirable as that of his fellow-savage in sub-tropical regions overspread with dense vegetation, with animal life in great abundance and variety and where half the attention must be given to species dangerous to man, often very small in size. In some hot humid forest districts, the European who should attempt to hunt or explore with bare feet and legs would be pricked or lacerated at almost every step of his progress, and probably get bitten by a serpent before the day's end. Yet the Indian passes his life there and, naked or half-naked, explores the unknown wilderness of thorns and has only his arrows to provide food for himself and his wife and children. He does not get pierced with thorns and bitten by serpents, because his eye is nicely trained to pick them out in time to save himself. He walks rapidly, but he knows every shade of green, every smooth and crinkled leaf in that dense tangle, full of snares and deceptions, through which he is obliged to walk; and much as leaf resembles leaf, he sets his foot where he can safely set it, or, quickly choosing between two evils, where the prickles and thorns are tenderest, or, for some reason known to him, hurt least. In like manner he distinguishes the coiled-up venomous snake, although it lies so motionless--a habit common to the most deadly kinds--and in its dull imitative colouring is so difficult to be distinguished on the brown earth, and among gray sticks and sere and variegated leaves.

A friend of mine, Fontana of Buenos Ayres, who has a life-long acquaintance with the Argentine Indians, expresses the opinion that at the age of twelve years the savage of the Pampas has completed his education and is thereafter able to take care of himself; but that the savage of the Gran Chaco--the sub-tropical Argentine territory bordering on Paraguay and Bolivia,--if left to shift for himself at that age would speedily perish, since he is then only in the middle of his long, difficult and painful apprenticeship. It was curious and pitiful, he says, to see the little Indian children in the Chaco, when their skins were yet tender, stealing away from their mother and trying to follow the larger ones playing at a distance. At every step they would fall and get pricked with thorns or cut with sharp-edged rushes and tangled in the creepers, and hurt and crying they would struggle on and in this painful manner at last learn where to set their feet.

The snake on the ground, coloured like the ground and shaped like the dead curved sticks or vines seen everywhere on the ground, and motionless like the vine, does not more closely assimilate to its surroundings than birds in trees often do--the birds which the Indian must also see. A stranger in these regions, even the naturalist with a sight quickened by enthusiasm, finds it hard to detect a parrot in a lofty tree, even when he knows that parrots are there; for their greenness in the green foliage and the correlated habit they possess of remaining silent and motionless in the presence of an intruder, make them invisible to him, and he is astonished that the Indian should be able to detect them. The Indian knows how to look for them; it is his trade, which is long to learn; but he is obliged to learn it, for his success in life, and even life itself, depends on it, since in the savage state Nature kills those who fail in her competitive examinations.

The reader has doubtless often seen those little picture-puzzles, variously labelled "Where's the Cat?" or "Mad Bull," or "Burglar," or "Policeman," or "Snake in the Grass," etc., in which the thing named and to be discovered is formed by branches and foliage and by running water and drapery and lights and shadows in the sketch. At first one finds it extremely difficult to detect this picture within a picture; and at last, with the suddenness with which one invariably detects a dull-coloured snake, seen previously but not distinguished--the object sought for appears, and is thereafter so plain to the eye that one cannot look at the sketch, even held at a distance, without seeing the cat or policeman, or whatever it happens to be. And after patiently studying some scores or hundreds of these puzzles one gets to know just how to find the thing concealed, and finds it quickly--almost at a glance at last. Now, the ingenious person that first invented this pretty puzzle probably had no thought of Nature, with her curious imitative and protective resemblances, in his mind; yet he might very well have taken the hint from Nature, for this is what she does. The animal that must be seen to be avoided, and the animal that must be seen to be taken, are there in her picture, sketched in with such cunning art that to the uninstructed eye they form only portions of branch and foliage and shadow and sunlight above, and dull-hued or variegated earth and stones and dead and withering herbage underneath.

It is possible that slight differences may exist in the seeing powers of different nations, due to the effect of physical conditions: thus, the inhabitants of mountainous districts and of dry elevated tablelands may have a better sight than dwellers in low, humid and level regions, although just the reverse may be the case. Among European nations the Germans are generally supposed to have weak eyes, owing, some imagine, to their excessive indulgence in tobacco, while others attribute the supposed decay to the form of type used in their books, which requires closer looking at than ours in reading. That they will deteriorate still further in this direction, and from being a spectacled people become a blind one, to the joy of their enemies, is not likely to happen, and probably the decadence has been a great deal exaggerated. Animals living in darkness become near-sighted, and then nearer-sighted still and so on progressively until the vanishing point is reached. In a community or nation a similar decline might begin from much reading of German books, or perpetual smoking of pipes with big china bowls, or from some other unknown cause; but the decay could not progress far, because there is nothing in man to take the place of sight, as there is in the blind cave rats and fishes and insects. And if we could survey mankind from China to Peru with all the scientific appliances which are brought to bear on the Board-school children in London and on the nation generally, the differences in the powers of vision in the various races, nations and tribes would probably appear very insignificant. The mistake which eye specialists and writers on the eye make is that they think too much about the eye. When they affirm that the conditions of our civilization are highly injurious to the sight, do they mean all the million conditions or sets of conditions embraced by our system, with the infinite variety of occupations and modes of living which men have, from the lighthouse-keeper to the worker underground, whose day is the dim glimmer of a miner's lamp? "An organ exercised beyond its wont will grow and thus meet increase of demand by increase of supply," Herbert Spencer says; but, he adds, there is a limit soon reached, beyond which it is impossible to go. This increase of demand with us is everywhere--now on this organ and now on that, according to our work and way of life, and the eye is in no worse case than the other organs. There are among us many cases of heart complaint; civilization, in such cases, has put too great a strain on that organ, and it has reached the limit beyond which it cannot go. And so with the eye. The total number of the defective among us is no doubt very large, for we know that our system of life retards--it cannot effectually prevent--the healthy action of natural selection. Nature pulls one way and we pull the other, compassionately trying to save the unfit from the consequences of their unfitness. The humane instinct compels us; but the cruel instinct of the savage, who hates the sick and the unfit as the inferior animals do, is less painful to contemplate than that mistaken or perverted compassion which seeks to perpetuate unfitness, and in the interest of suffering individuals inflicts a lasting injury on the race.

Pelleschi, in his admirable book on the Chaco Indians, says that malformations are never seen in these savages, that physically they are all perfect men; and he remarks that in their exceedingly hard struggle for existence in a thorny wilderness, beset with perils, any bodily defect or ailment would be fatal. And as the eye in their life is the most important organ, it must be an eye without flaw. In this circumstance only do savages differ from us--namely, in the absence or rarity of defective eyes among them; and when those who, like Mr. Brudenell Carter, believe in the decadence of the eye in civilized man quote Humboldt's words about the miraculous sight of South American savages, they quote an error. It is not strange that Humboldt should have fallen into it, for, after all, he had only the means which we all possess of finding out things--a limited sight and a fallible mind. Like the savage, he had trained his faculties to observe and infer, and his inferences like those of the savages, were sometimes wrong.

The savage sight is no better than ours for the simple reason that a better is not required. Nature has given to him, as to all her creatures, only what was necessary and nothing for ostentation. Standing on the ground, his horizon is a limited one; and the animals he preys on, if often sharper-eyed and swifter than he, are without intelligence, and thus things are made equal. He can see the rhea as far as the rhea can see him; and if he possessed the eagle's far-seeing faculty it would be of no advantage to him. The high-soaring eagle requires to see very far, but the low-flying owl is near-sighted. And so on through the whole animal world: each kind has sight sufficient to find its food and escape from its enemies, and nothing beyond. Animals that live close to the surface have a very limited sight. Moreover, other faculties may usurp the eye's place, or develop so greatly as to make the eye of only secondary importance as an organ of intelligence. The snake offers a curious case. No other sense seems to have developed in it, yet I take the snake to be one of the nearest-sighted creatures in existence. From long observation of them I am convinced that small snakes of very sluggish habits do not see distinctly farther than from one to three yards. But the snake is the champion faster in the animal world and can afford to lie quiescent until the wind of chance blows something eatable in its way; hence it does not require to see an object distinctly until almost within striking distance. Another remarkable case is that of the armadillo. Of two species I can confidently say that, if they are not blind, they are next door to blindness; yet they are diurnal animals that go abroad in the full glare of noon and wander far in search of food. But their sense of smell is marvellously acute, and, as in the case of the mole, it has made sight superfluous. To come back to man: if, in a state of nature, he is able to guess the character of objects nine times in ten, or nineteen in twenty, seen as far off as he requires to see anything, his intellectual faculties make a better sight unnecessary. If the armadillo's scent had not been so keen and man had not been gifted with nimble brains, the sight in both cases would have been vastly stronger; but the sharpening of its sense of smell has dimmed the armadillo's eyes and made him blinder than a snake; while man (from no fault of his own) is unable to see farther than the wolf and the ostrich and the wild ass.

MECHANISM IN THOUGHT AND MORALS

DR. OLIVER WENDELL HOLMES

[Dr. Holmes was at once a distinguished physician, poet,
novelist, and wit. His "Autocrat of the Breakfast Table" is
one of the most charming books ever written, his poetry and
essays are of even greater popularity. Dr. Holmes's Works are
published in fourteen volumes by Houghton, Mifflin & Co.,
Boston and New York, copyright in various editions. The essay
from which extracts follow is in the eighth volume.]

Do we ever think without knowing that we are thinking? The question may be disguised so as to look a little less paradoxical. Are there any mental processes of which we are unconscious at the time, but which we recognize as having taken place by finding certain results in our minds?

That there are such unconscious mental actions is laid down in the strongest terms by Leibnitz, whose doctrine reverses the axiom of Descartes into _I am, therefore I think_. The existence of unconscious thought is maintained by him in terms we might fairly call audacious, and illustrated by some of the most striking facts bearing upon it. The "insensible perceptions," he says, are as important in pneumatology [spiritual philosophy] as corpuscles are in physics.--It does not follow, he says again, that, because we do not perceive thought, it does not exist.--Something goes on in the mind which answers to the circulation of the blood and all the internal movements of the viscera.--In one word, it is a great source of error to believe that there is no perception in the mind but those of which it is conscious.

This is surely a sufficiently explicit and peremptory statement of the doctrine, which, under the names of "latent consciousness," "obscure perceptions," "the hidden soul," "unconscious cerebration," "reflex action of the brain," has been of late years emerging into general recognition in treatises of psychology and physiology.

His allusion to the circulation of the blood and the movements of the viscera, as illustrating his paradox of thinking without knowing it, shows that he saw the whole analogy of the mysterious intellectual movement with that series of reflex actions so fully described half a century later by Hartley, whose observations, obscured by wrong interpretation of the cerebral structure and an insufficient theory of vibrations which he borrowed from Newton, are yet a remarkable anticipation of many of the ideas of modern physiology, for which credit has been given so liberally to Unzer and Prochaska. Unconscious activity is the rule with the actions most important to life. The lout who lies stretched on the tavern bench, with just mental activity enough to keep his pipe from going out, is the unconscious tenant of a laboratory where such combinations are being constantly made as never Wöhler or Berthelot could put together; where such fabrics are woven, such colours dyed, such problems of mechanism solved, such a commerce carried on with the elements and forces of the outer universe, that the industries of all the factories and trading establishments in the world are mere indolence and awkwardness and unproductiveness compared to the miraculous activities of which his lazy bulk is the unheeding centre. All these unconscious or reflex actions take place by a mechanism never more simply stated than in the words of Hartley, as "_vibrations_ which ascend up the sensory nerves first, and then are detached down the motory nerves, which communicate with these by some common trunk, plexus, [network] or ganglion [knot]." The doctrine of Leibnitz, that the brain may sometimes act without our taking cognizance of it, as the heart commonly does, as many internal organs always do, seems almost to belong to our time. The readers of Hamilton and Mill, of Abercrombie, Laycock and Maudsley, of Sir John Herschel, of Carpenter, of Lecky, of Dallas, will find many variations on the text of Leibnitz, some new illustrations, a new classification and nomenclature of the facts; but the root of the matter is all to be found in his writings.

I will give some instances of work done in the underground workshop of thought--some of them familiar to the readers of the authors just mentioned. We wish to remember something in the course of conversation. No effort of the will can reach it; but we say, "Wait a minute, and it will come to me," and go on talking. Presently, perhaps some minutes later, the idea we are in search of comes all at once into the mind, delivered like a prepaid bundle, laid at the door of consciousness like a foundling in a basket. How it came there we know not. The mind must have been at work groping and feeling for it in the dark: it cannot have come of itself. Yet, all the while, our consciousness, so far as we are conscious of our consciousness, was busy with other thoughts.

In old persons, there is sometimes a long interval of obscure mental action before the answer to a question is evolved. I remember making an inquiry of an ancient man, whom I met on the road in a waggon with his daughter, about a certain old burial-ground which I was visiting. He seemed to listen attentively; but I got no answer. "Wait half a minute or so," the daughter said, "and he will tell you." And sure enough, after a little time he answered me and to the point. The delay here, probably, corresponded to what machinists call "lost time," or "back lash" in turning an old screw, the thread of which is worn. But, within a fortnight, I examined a young man for his degree in whom I noticed a certain regular interval, and a pretty long one, between every question and its answer. Yet the answer was, in almost every instance, correct, when at last it did come. It was an idiosyncrasy, I found, which his previous instructors had noticed. I do not think the mind knows what it is doing in the interval, in such cases. This latent period, during which the brain is obscurely at work, may, perhaps, belong to mathematicians more than others. Swift said of Sir Isaac Newton that, if one were to ask him a question, "he would revolve it in a circle in his brain, round and round and round" (the narrator here describing a circle on his own fore-head), "before he could produce an answer."

I have often spoken of the same trait in a distinguished friend of my own, remarkable for his mathematical genius, and compared his sometimes long-deferred answer to a question with half a dozen others stratified over it, to the thawing out of the frozen words as told of by Baron Munchausen and Rabelais, and nobody knows how many others before them.

I was told, within a week, of a business man in Boston, who, having an important question under consideration, had given it up for the time as too much for him. But he was conscious of an action going on in his brain which was so unusual and painful as to excite his apprehensions that he was threatened with palsy, or something of that sort. After some hours of this uneasiness, his perplexity was all at once cleared up by the natural solution of his doubt coming to him--worked out, as he believed, in that obscure and troubled interval.

The cases are numerous where questions have been answered, or problems solved, in dreams, or during unconscious sleep. Two of our most distinguished professors in this institution have had such an experience, as they tell me; and one of them has often assured me that he never dreams. Somnambulism and double-consciousness offer another series of illustrations. Many of my audience remember a murder case, where the accused was successfully defended, on the ground of somnambulism, by one of the most brilliant of American lawyers. In the year 1686 a brother of Lord Culpepper was indicted at the Old Bailey for shooting one of the guards and acquitted on the same ground of somnambulism; that is an unconscious and, therefore, irresponsible state of activity.

A more familiar instance of unconscious action is to be found in what we call "absent" persons--those who, while wide awake, act with an apparent purpose, but without really knowing what they are doing; as in La Bruyère's character, who threw his glass of wine into the backgammon board and swallowed the dice.

There are a vast number of movements which we perform with perfect regularity while we are thinking of something quite different--"automatic actions of the secondary kind," as Hartley calls them, and of which he gives various examples. The old woman knits; the young woman stitches, or perhaps plays her piano and yet talks away as if nothing but her tongue were busy. Two lovers stroll along side by side, just born into the rosy morning of their new life, prattling the sweet follies worth all the wisdom that years will ever bring them. How much do they think about that wonderful problem of balanced progression which they solve anew at every step?

We are constantly finding results of unperceived mental processes in our consciousness. Here is a striking instance, which I borrow from a recent number of an English journal. It relates to what is considered the most interesting period of incubation in Sir William Rowan Hamilton's discovery of quaternions. The time was the 15th of October, 1843. On that day, he says in a letter to a friend, he was walking from his observatory to Dublin with Lady Hamilton, when, on reaching Brougham Bridge, he "felt the galvanic circle of thought close; and the sparks that fell from it were the fundamental relations between i, j, k," just as he used them ever afterwards.

Still another instance of the spontaneous evolution of thought we may find in the experience of a great poet. When Goethe shut his eyes and pictured a flower to himself, he says that it developed itself before him in leaves and blossoms. The result of the mental process appeared as pictured thought; but the process itself was automatic and imperceptible.

There are thoughts that never emerge into consciousness, which yet make their influence felt among the perceptible mental currents, just as the unseen planets sway the movements of those which are watched and mapped by the astronomer. Old prejudices that are ashamed to confess themselves nudge our talking thought to utter their magisterial veto. In hours of languor, as Mr. Lecky has remarked in his "History of Rationalism," the beliefs and fancies of obsolete conditions are apt to take advantage of us. We know very little of the contents of our minds until some sudden jar brings them to light, as an earthquake that shakes down a miser's house brings out the old stockings full of gold and all the hoards that have been hidden away in holes and crannies.

We not rarely find our personality doubled in our dreams and do battle with ourselves, unconscious that we are our own antagonists. Dr. Johnson dreamed that he had a contest of wit with an opponent, and got the worst of it: of course he furnished the wit for both. Tartini heard the Devil play a wonderful sonata and set it down on waking. Who was the Devil but Tartini himself? I remember, in my youth, reading verses in a dream, written, as I thought, by a rival fledgling of the Muse. They were so far beyond my powers that I despaired of equalling them; yet I must have made them unconsciously as I read them. Could I only have remembered them waking!

But I must here add another personal experience, of which I will say beforehand--somewhat as honest Isaak Walton said of his pike, "This dish of meat is too good for any but anglers or honest men"--this story is good only for philosophers and very small children. I will merely hint to the former class of thinkers, that its moral bears on two points: first, the value of our self-estimate, sleeping--possibly, also, waking; secondly, the significance of general formulæ when looked at in certain exalted mental conditions.

I once inhaled a pretty full dose of ether, with the determination to put on record, at the earliest moment of regaining consciousness, the thought I should find uppermost in my mind. The mighty music of the triumphal march into nothingness reverberated through my brain, and filled me with a sense of infinite possibilities, which made me an archangel for the moment. The veil of eternity was lifted. The one great truth which underlies all human experience and is the key to all the mysteries that philosophy has sought in vain to solve, flashed upon me in a sudden revelation. Henceforth all was clear: a few words had lifted my intelligence to the level of the knowledge of the cherubim. As my natural condition returned, I remembered my resolution; and, staggering to my desk, I wrote, in ill-shaped, straggling characters, the all embracing truth still glimmering in my consciousness. The words were these (children may smile; the wise will ponder): "_A strong smell of turpentine prevails throughout._"

My digression has served at least to illustrate the radical change which a slight material cause may produce in our thoughts, and the way we think about them. If the state just described were prolonged, it would be called insanity. I have no doubt that there are many ill-organized perhaps over-organized human brains, to which the common air is what the vapour of ether was to mine: it is madness to them to drink in this terrible burning oxygen at every breath; and the atmosphere that enfolds them is like the flaming shirt of Nessus.