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CHAPTER XIII. MAN AND THE APE.

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the primary object of the present essay is to ascertain whether the conclusion arrived at by mr. darwin and other writers as to the origin of man—that he has sprung from the ape by simple descent—can be depended on, and if not, what is the nature of man’s relationship to the animal kingdom.

without further preface, i shall proceed to consider as briefly as possible the main arguments adduced by mr. darwin in support of this conclusion.364 those which are derived from the consideration of physical data appear to me to be of comparatively small importance, since they may be admitted without seriously affecting the question at issue. they are almost all connected with the fact that man is “constructed on the same general type or model with other mammals.” thus it is with the brain, every chief fissure and fold of which is declared to be developed in the brain of the orang equally with that of man. their constitutional habit, however, appears also to be the same. thus man and monkeys are liable to many of the same non-contagious diseases; medicines produce the same effect on both, and most mammals exhibit the mysterious law of periodicity in various diseases. these are interesting facts, but the279 most important for the argument of the ape-descent of man are those which show the existence in the human body of certain rudimentary organs and structures which are fully developed with some of the lower animals. it is possible, however, to explain this phenomenon without having recourse to the hypothesis of a simple ape-descent; even if it be admitted with m. broca, that in the parallel between man and the anthropoids, the comparison of organs shows only some slight differences.365 this may be granted even as to the brain, and that “the immense superiority of man’s intelligence depends, not on the anatomical structure of his brain, but on its volume and power.”366 but then, if such is the case, it is all the more difficult to account for the vast difference which, says broca, a comparison of function reveals, and which led m. gratiolet to exclaim that, although man is indeed by his structure a monkey, yet by his intelligence he is a god.367

while admitting that physiological considerations reveal a much wider interval between man and the anthropoid apes than anatomical data require, m. broca would hardly allow that the former exhibits anything peculiar in his mental action. so, also, mr. darwin says that man and the higher mammals “have some few instincts in common. all have the same senses, intuitions, and sensations—similar passions, affections, and emotions, even the more complex ones; they feel wonder and curiosity; they possess the same faculties280 of imitation, attention, memory, imagination, and reason, though in very different degrees.”368 the faculty of articulate speech, moreover, is said not in itself to offer “any insuperable objection to the belief that man has been developed from some lower form;” while the taste for the “beautiful” is shown not to be peculiar to the human mind.369 the moral sense is supposed by mr. darwin to be the most distinctive characteristic of man; but even this is asserted to have been developed out of the social instincts which man and many of the lower animals have in common.370 finally, self-consciousness, abstraction, &c., even if peculiar to man, are declared to be “the incidental results of other highly-advanced intellectual faculties;”371 and these again are mainly due to the continued use of a highly-developed language, which originated in “the imitation and modification, aided by signs and gestures, of various natural sounds, the voices of other animals and man’s own instinctive cries.”372

if, however, all this be true, how are we to account for the wonderful intellectual superiority of man? haeckel gives an explanation which, although ingenious, is far from satisfactory. he says that it is owing to the fact that “man combines in himself several prominent peculiarities, which only occur separately among other animals.” the most important of these are the superior structure of the larynx, the degree of brain or soul development, and that of the extremities, the upright walk, and, lastly, speech. but, says281 haeckel, “all these prerogatives belong singly to other animals—birds with highly-organised larynx and tongue, such as the parrot, &c., can learn to utter articulate sounds as perfectly as man himself. the soul’s activity exists among many of the higher animals, particularly with the dog, the elephant, and the horse, in a higher degree of cultivation than with man when most degraded. the hand, as a mechanical instrument, is as highly developed among the anthropoid apes as with the lowest men. finally, man shares his upright walk with the penguin and other animals, while capacity for locomotion is more fully and more perfectly developed among many animals than with man.” haeckel concludes, therefore, that it is “solely the fortunate combination of a higher organisation of several very important organs and functions which raises most men, but not all, above the animals.”373 this explanation, however, appears rather to increase the difficulty than to remove it. some of haeckel’s statements might probably be challenged with success; but even admitting their truth, what cause can be given of the marvellous combination in man, of qualities possessed separately by animals, the highest in the class to which they belong?

mr. darwin justly remarks, that282 “the belief that there exists in man some close relation between the size of the brain and the development of the intellectual faculties, is supported by the comparison of the skulls of savage and civilised races of ancient and modern peoples, and by the analogy of the whole vertebrate series.”374 there must, indeed, be a certain agreement between the brain and its intellectual products, and hence the large size of the human brain requires that the mental phenomena of man should be of a vastly superior nature to those presented by the lower animals. whether, according to the developmental view of the correspondence between human and brute mental faculties, the lower races of man, as compared with animals, really exhibit an intellectual superiority commensurate with the largeness of their brains, may be questioned. mr. wallace, indeed, declares that they do not, and he goes so far as to say that “a brain slightly larger than that of the gorilla would, according to the evidence before us, fully have sufficed for the limited mental development of the savage.”375 this opinion is correct, on the assumption that animal and human mental action is perfectly analogous, and mr. wallace would undoubtedly be right in asserting that the savage possesses a brain “quite disproportionate to his actual requirements,” if by this phrase is meant his mere animal wants. but the savage is a man, and the size of brain required by him must be judged of, not by the degree of intellectual action he exhibits, but by its accompaniments—not by quantity, but by quality.

the source of man’s superiority must be sought in an examination of his mental faculties, and yet the inquiry is vitiated at the very commencement, by the283 assumption that the mind of man differs from that of the animal only in the degree of its activity. i am prepared to admit that the higher mammalia, at least, have the power of reasoning, with all the faculties which are essential to its exercise. but this very fact makes it utterly incomprehensible how the result of human mental activity can be so superior, unless some further principle or faculty than those which the animal mind possesses operates in that of man. what this principle or faculty is, may be shown by reference to certain facts connected with language. mr. darwin ascribes the origin of human speech to imitation and modification of natural sounds and man’s own instinctive utterances.376 that the primitive elements of man’s language were thus obtained is doubtless true. something else, however, is required to explain the phenomena presented by the languages of uncultured peoples. such, for instance, cannot have been the origin of certain ideas which are apparently common to the minds of all peoples however savage. it has been said that these peoples, although having names for every particular object, have no words to express a class of objects. this statement must be received with caution. but if absolutely true in the sense intended, it cannot be denied that nearly all primitive languages have words denoting colours, and these by their very nature, as expressive of attributes, are applicable to a series of objects.

now there is not the slightest reason to believe that animals have any idea of qualities, as such. even the284 taste for the beautiful, which mr. darwin tells us is not unknown to various animals—especially birds, has relation to the object which attracts by its colour, &c., and not to the colour itself. but it is just this perception of the qualities of objects which is at the foundation, and forms the starting point, of all human progress. the essential instrument of intellectual development, articulate language, was first prompted by such a perception, and it was in the recognition of the qualities of actions, by reflection on their consequences, that the moral sense was gradually evolved. it can hardly be that a power which has had so wonderful an effect, and one which is so different from anything met with among the lower animals, can be referred to any of the ordinary faculties which these possess. if not, we must ascribe it to a new faculty altogether, a kind of spiritual insight, which can be explained only as resulting from the addition of a principle of activity superior to that which is the seat of the animal life. if we were to trace the beginning of every single branch of human culture, it would be found to have originated in the exercise of such a faculty of reflection as that here described. the elements of knowledge man possesses in common with the animals around him; but these have not built up any superstructure, because they have no spiritual insight such as will enable them to analyse those elements, and thus to fit them for re-combination into that wonderful series of forms which they have taken in the human mind.

it is hardly necessary to discuss here the nature of the principle which thus shows its energy in the mind285 of man. whether it is the cause or the effect of the refined organisation exhibited by the human body need not now be considered. if the latter, however, it may be objected that—assuming the human bodily organism to have been derived by descent from a lower animal form, according to the principles of natural selection—the intellectual faculty peculiar to man must have had analogous origin. to this it might be answered that man’s special faculty could not have been derived from an animal organism which does not itself possess it; but it is advisable rather to test that conclusion by a consideration of the physical data, and to see how far the argument for natural descent can be supported. according to this view, the tendency to the bipedal character was the first to become operative in the gradual development of man out of the ape. the erect form is supposed, however, to have been assumed that the arms and hands might have full play,377 and it is evident that the free use of these would not have been of any special advantage without an increased brain-activity to guide them. probably the changes required in the physical structure would be concomitant, but if they had a starting point it would surely be in the brain rather than in the extremities.

the great development of the encephalon in man as compared with the monkey tribe would, in fact, require all the other supposed changes. thus the greatly increased size and weight of the brain and its bony case, combined with the position of the foramen286 magnum at the base of the skull, would necessitate the erect position of the body, and this would supply the arms and upper part of the trunk with the required freedom of movement. these changes would be accompanied by the modification of the pelvis and lower limbs, while the increased sensitiveness of the skin, resulting from man’s more refined nervous structure, will sufficiently account for its general nakedness,378 without supposing, with mr. darwin, the influence of sexual selection.379 it is therefore in reality only the large size of the human brain that has to be accounted for, and this is by no means easy on the principle of natural selection. no doubt, with the increased activity of the mental powers, the brain would become more voluminous. but what was to determine that increased activity? it can only have been an improvement in the conditions of existence, to which man’s supposed ape progenitors were subjected, for which no sufficient reason can be given. moreover, those progenitors would be subjected to the inevitable struggle for existence—a struggle which, even with man, in an uncivilised state, has a tendency to brutalise rather than to humanise. under these conditions it would seem to be impossible for man to have raised himself to so great a superiority over his nearest allies as even the lowest savage exhibits. “his absolute erectness of posture, the completeness of his nudity, the harmonious perfection of his hands, the almost infinite capacities of his brain, constitute,” says287 mr. wallace, “a series of correlated advances too great to be accounted for by the struggle for existence of an isolated group of apes in a limited area,”380 as mr. darwin’s hypothesis supposes.

while firmly convinced, on the grounds already stated, that man cannot have been derived from the ape by descent with natural selection, i am by no means prepared to admit that he may not have been so derived under other conditions. although man undoubtedly has a mental faculty of the utmost importance which the animals do not possess, agreeing with his superiority of physical structure, there can be no question that, both physically and mentally, he is most intimately allied to the members of the animal kingdom. before endeavouring to furnish a solution of the difficult question of the origin of man under these conditions, i would point out, what is so ably insisted on by m. broca,381 that transformism, to use the continental term, is wholly distinct from “natural selection,” or any other mode by which the transformation may be originated or effected. this is a most important consideration, and one which mr. darwin has incidentally referred to.382 that man is the final term in a process of evolution, the beginning of which we cannot yet trace, appears to me to be a firmly established truth. the descent of man from the ape under the influence of external conditions is, however, a totally different proposition, and one of288 which no actual proof has yet been furnished, the argument really amounting to this, that the correspondences between man and the higher mammals render it more likely that he has descended from the ape than that he has been specially created. this may be true, and yet those correspondences be owing to a very different cause from the one thus supposed for them.

mr. herbert spencer affirms that “successive changes of conditions would produce divergent varieties or species” of the organisms subject to them, apart from the influence of “natural selection,” which, in the absence of such successive changes of conditions, would effect “comparatively little.”383 it is to the latter especially mr. spencer traces the gradual evolution of nature, on the process of which he has thrown so much light. thus, when treating elsewhere of that evolution, he says, “while we are not called on to suppose that there exists in organisms any primordial impulse which makes them continually unfold into more heterogeneous forms; we see that a liability to be unfolded arises from the actions and reactions between organisms and their fluctuating environments. and we see that the existence of such a cause of development pre-supposes the non-occurrence of development where this fluctuation of actions and reactions does not come into play.”384 it is evident that this theory, like that of mr. darwin, supposes the occurrence of slight structural changes which, in the absence of289 knowledge as to their exciting causes, may be described as “spontaneous,” and the perpetuation of which is the establishment of new forms or species. but among domestic animals, and by analogy we may assume, therefore, among wild animals, variation in the way supposed is not the only mode by which the physical structure may be modified. various instances of sudden change have been collected which are very difficult to deal with, and they have led mr. huxley to remark that mr. darwin’s position “might have been even stronger than it is if he had not embarrassed himself with the aphorism ‘natura non facit saltum,’ which turns up so often in his pages.” mr. huxley adds “that nature does make jumps now and then, and a recognition of the fact is of no small importance in disposing of many minor objections to the doctrine of transmutation.”385 minor objections may certainly be thus removed, but only by introducing one of much greater moment. if, as mr. spencer says, “natural selection is capable of producing fitness between organisms and their circumstances,”386 it must be by the perpetuation of slight changes, and there does not, indeed, appear to be any room in the hypothesis of natural selection for the saltatory movements which it is so necessary to explain.

the changes which organisms undergo, whether sudden or gradual, and whatever their approximate exciting cause, take place in pursuance of the evolution of organic nature, and there can be no doubt that290 this proceeds under the guidance of law. professor owen expresses this fact in saying that “generations do not vary accidentally in any and every direction, but in preordained, definite, and correlated courses.”387 this may be accepted as expressing a general truth, subject to some qualification of the word “preordained.” it is not exactly true, however, for variations are not always regular and orderly. within certain limits, indeed, they would seem to take place in any direction, but there is always a tendency for them to accumulate in that course along which they meet with the least resistance. this is in accordance with the principle laid down by mr. herbert spencer, that everything tends towards equilibration, the state being one not of absolute but of moving equilibrium, while “throughout evolution of all kinds there is a continual approximation, and more or less complete maintenance of this moving equilibrium.”388 the ultimate result is that, “when through a change of habit or circumstance an organism is permanently subject to some new influence, or different amount of an old influence, there arises, after more or less disturbance of the old rhythms, a balancing of them around the new average conditions produced by this additional influence.”389 it is evident that the variations which have been originated before the attainment of the state of temporary stability thus established would have little chance of being perpetuated; and we have probably here the explanation of the291 fact that the progress of evolution reveals itself so often by sudden movements. in these cases, where the disturbing influence has rendered the equilibrium of the organism affected more or less unstable, a new centre of equilibrium will be formed, and the appearance of a fresh specific form be the result.

however fitted this explanation may be to account for the gaps which so often present themselves in developmental series of animal structures, it is far from sufficient to account for the origin of man, at least on the assumption of evolution governed merely by mechanical principles. neither man nor animals, in fact, could have come into being at all unless there had been an organic necessity, quite independent even of the general average effects of the relations of living bodies to their environments, insisted on by mr. spencer. that these agencies have been very influential in the evolution of organic nature is undoubtedly true. but their influence in this respect depends altogether on the organism on which they act being in a condition of unstable equilibrium. mr. spencer declares, when speaking of the condition of homogeneity being a condition of unstable equilibrium, that this instability is “consequent on the fact that the several parts of any homogeneous aggregation are necessarily exposed to different forces—forces that differ either in kind or amount.”390 this may be true in relation to animal and vegetable forms, whose germs are supposed not to show the slightest trace of the future organism, although even as to these292 mr. spencer can say that “doubtless we are still in the dark respecting those mysterious properties which make the germ, when subject to fit influences, undergo the special changes beginning this series of transformations.”391 but the unstable condition of the primeval homogeneous substance of nature could not be due to the cause assigned. for it requires the impossible case of certain forces, the action of which is supposed to result in the condition of instability, existing outside of that substance which, as being identified with the absolute, we must assume to be present throughout all space. the notion of an universally diffused homogeneous substance, acted on by external forces, appears to be contrary to reason; and the proper explanation of the original condition of instability would seem to be that it is natural to the primeval substance as the result of an innate energy, the internal force which constitutes its vitality. but this substance cannot have been merely “material.” there is just as little room for transition from the inorganic to the organic as from the animal to man; there is but one satisfactory starting-point—nature itself viewed as organic.

if such is the case when the changes observable in nature are viewed as strictly evolutional, much more so is it when they are traced to the lower activity of natural selection. mr. j. j. murphy well remarks that293 “the facts of variability being the greatest in the lowest organisms, while progress has been most rapid among the higher ones, shows that there is something in organic progress which mere natural selection among spontaneous variations will not account for.”392 elsewhere the same writer declares that “no solution of the questions of the origin of organisation and the origin of organic species can be adequate which does not recognise an organising intelligence over and above the common laws of matter”—i.e., the laws of self-adaptation to circumstances and natural selection.393 this organising intelligence is supposed to have been bestowed once for all on vitalised matter by the creator, so as to prevent the necessity of separately organising each particular structure,394 although it is suggested that man’s spiritual nature may be a direct result of creative power.395 mr. wallace objects to the law of “unconscious intelligence,” that “it has the double disadvantage of being both unintelligible and incapable of any kind of proof.”396 this is true enough, but it has the equally serious defect of reintroducing the notion of special “creation,” with all the difficulties attendant on the origin of matter, and the separate existence of independent spiritual and material substances.

mr. wallace himself is so much struck with the imposing position occupied by man that he thinks that “a superior intelligence has guided the development of man in a definite direction and for a special purpose, just as man guides the development of many animal and vegetable forms.”397 he supposes, more294over, that “the whole universe is not merely dependent on, but actually is, the will of higher intelligences, or of one supreme intelligence.”398 it seems to me, although mr. wallace thinks otherwise, that this notion completely undermines the hypothesis of natural selection. if not only the whole universe, but also a particular portion of it—man—has been divinely “willed,” analogy will lead us to believe that every other portion of the whole has thus originated.

the difficulties attendant on theories such as those of mr. murphy and mr. wallace, and the unsatisfactory explanation afforded by the theory of evolution, as usually understood, of the origin of man, have led me to the opinion that nature as a whole is organic, and that man is the necessary result of its evolution. not only so, however; man must be viewed as the real object of the evolution of nature viewed as a living organism. without him nature itself would be imperfect, and all lower animal forms must, therefore, be considered as subsidiary to the human organism, and as so many stages only towards its attainment. but if living nature is an organic whole, its several parts must be intimately connected. hence the numerous correspondences between man and the higher mammals cannot be accidental or even merely designed similarities. they betoken an actual and intimate connection between the organisms presenting them, and such an one as is consistent only with a derivation of one from the other. this view295 differs from that of mr. darwin, not in the fact of man’s derivation from the ape, but in the mode and conditions under which it has taken place. derivation, by virtue of an inherent evolutional impulse, is totally different from simple descent, aided by natural selection. in the latter case the appearance of man may be described as in some sense accidental; in the former, not only is it necessary, but it is that for which all evolution has taken place, the only condition, in fact, under which evolution was possible.

how far such a development of organic forms as i have supposed is consistent with design is a difficult question. it is apparent that when nature is conceived of as forming an organic whole, the universe becomes identified with the absolute, of whose being relative nature is merely an expression. but is not the possession by relative existences of intellectual faculties, and of the marvellous power of insight or reflection, evidence that the same powers belong also to the absolute being? the possession by man of intelligence is, in fact, proof that organic nature is intelligent. still, however, the need of design is not apparent. granting that relative nature has been evolved out of the absolute existence, such evolution can have taken only one course—that which led to man, who could appear only when the conditions of nature were fitted for him, and who must appear when those conditions were so fitted. moreover, as man was from the beginning the object of organic evolution, this must have taken place along the line which led to him, without any actually preconceived design or intention other than that which is implied in the pre296knowledge of man’s appearance. it does not follow, however, that other branches of organic nature besides that which ended in man may not have reached a stage of structural perfection. no doubt they have so done, and thus we can understand how it is that certain animals seem to have been, as professor owen asserts, “predestined and prepared for man.” the fitness pointed out by our great anatomist “of the organisation of the horse and ass for the needs of mankind, and the coincidence of the origin of the ungulates having equine modifications of the perissodactyle structure with the period immediately preceding, or coincident with, the earliest evidence of the human race,” is certainly remarkable.399 i cannot see in these facts, however, anything more than a necessary coincidence arising from the progress of evolution along different planes. it is possible, however, that professor owen may mean little more than this, and that he would be satisfied to admit the identity between the “predetermining” agent and organic nature, acting by virtue of the laws of its own evolutional impulse. so at least may be supposed from the fact that he rejects “the principle of direct or miraculous creation,” and recognises “a ‘natural law or secondary cause’ as operative in the production of species in orderly succession and progression.”400 it is difficult to understand how otherwise there could be an “innate tendency to deviate from the parental type.”

before concluding, reference should be made to297 certain facts connected with the development of the brain and the human organism generally, which at first sight seem to be quite irreconcilable with the notion of man’s derivation from the ape, even under the conditions i have proposed. thus, m. pruner bey has shown that in man and the anthropomorphous apes there exists “an inverse order of the final term of development in the sensitive and vegetative apparatus, and in the systems of locomotion and reproduction.” the same inverse order is exhibited in the development of individual organs. thus it is, says pruner bey, with a portion of the permanent teeth; welcher makes a similar remark as to the modifications of the base of the skull in relation to the sphenoidal angle of virchow; and gratiolet points out an analogous fact in the development of the brain. the language of the great french anatomist is very precise. he says: “with man and the adult anthropormorphous apes there exists a certain resemblance in the mode of arrangement in the cerebral folds which has imposed on some persons and on which they have strongly insisted. but this result is attained by an inverse process (marche inverse). in the monkey the temporosphenoidal convolutions which form the middle lobe appear and perfect themselves before the anterior convolutions which form the frontal lobe. with man, on the contrary, the frontal convolutions appear the first, and those of the middle lobe show themselves the last.” in referring to these facts, m. de quatrefages declares that298 “when two organised beings follow an inverse course in their development, the more highly developed of the two cannot have descended from the other by means of evolution.”401 if by evolution is meant simple descent under the influence of natural selection and modification of external conditions, this conclusion is certainly correct. it is true that, contrary to the opinion expressed by gratiolet, that “the human brain differs the more from that of the monkey the less it is developed, and an arrest of development can only exaggerate this natural difference.”402 m. carl vogt declares that the human brain may, under certain conditions, not only externally resemble that of the higher apes, but also that the superior portion of it (parties vo?tées) in microcephalic idiots is really developed after the simian type,403 the skull itself having both simian and human elements.404 but does not the fact that the lower part of the microcephalic skull, and the portion of the brain which is the earliest developed, are formed on the human type, amply justify the assertion of gratiolet that “the microcephale, however degraded, is not a brute, but only a modified man?” is it not evident, moreover, that however highly an ape brain may be developed, it could not become like that of a man, at least by descent with natural selection? it is different, however, if we view man as the necessary product of the evolution of organic nature. we may well believe that when the sudden advance from the ape structure to that of man was made, under the conditions above proposed, the great increase in the size299 of the brain and the change in the position of the foramen magnum were accompanied by an alteration in the order of development, not only of the different parts of the brain, but also of the internal apparatus as pointed out by m. pruner bey. but the advance having once taken place, the human type can no more be lost; and although the approach to the simian type which appears in the abnormal microcephalic brain evidences the intimate connection between man and the ape, yet it furnishes no disproof of derivation, one from the other, by the agency of internal evolutional impulse.

in conclusion, i would again refer to the fact, so strongly insisted on by m. broca, that the truth of the theory of evolution is not dependent on that of the hypothesis of natural selection. the great defect of “natural selection” as an agent in organic evolution, is that it cannot do more than perpetuate certain structural peculiarities, the appearance of which it is powerless to explain. the hypothesis is properly defined as “natural selection among spontaneous variations;” and it is the appearance of these variations which constitutes the most important part of the problem. they can be explained only on the assumption of “an internal tendency to deviate from the parental type;” and granting that this tendency results from a necessary evolution of nature viewed as an organic whole, there is no difficulty in accounting for all the facts dwelt on by mr. darwin without supposing the derivation of man from the ape by simple descent, although not without identifying the universe with deity, and viewing its various manifestations as his organs.

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