Creation or Evolution? A Philosophical Inquiry

by George Ticknor Curtis

Whoever will carefully examine Mr. Darwin's hypothesis of the descent of man as an animal, will find that commencing at a point opposite to that at which Plato began his speculations, the modern naturalist assumes the existence of a very low form of animated and organized matter, destitute of anything in the nature of reason, even if acting under what may be called instinctive and unconscious impulses, imposed upon it by the preordained laws by which animated matter is to act. By some process of generation, either bi-sexual or uni-sexual or non-sexual, this very low type of animal is endowed with a power of reproducing other individuals of the same structure and habits. In process of time, for which we must allow periods very much longer than those of which we are accustomed to think in relation to recorded history, the individuals of this species become enormously multiplied. A struggle for existence takes place between these very numerous individuals; and in this struggle there comes into operation the law to which Mr. Darwin has given the name of "natural selection," which is but another name for a series of events. He does not mean by this term to imply a conscious choice on the part of the animals, nor an active power or interfering deity. He employs it to express a constantly occurring series of events or actions, by which, in certain circumstances, animals secure themselves against the tendency to destruction which is caused by the great disparity between their numbers and the amount of food that is accessible to them, or by the unfavorable influences of a change of climate upon so great a body of individuals. He calls this series of events or actions natural selection, in order, as I understand, to compare what takes place in nature with what takes place when a breeder of animals purposely selects the most favorable individuals for the purpose of improving or varying the breed. In nature, the selection is supposed to operate as follows: The strongest and most active individuals of a species of animals have the best chance of securing the requisite amount of food from the supply that is insufficient for all. They do this by their greater fleetness in overtaking the common prey, or by making war upon the more feeble or inactive of their fellows; and numerous individuals are either directly destroyed by this warfare, or are driven off from the feeding-ground and perish for want of nourishment. Thus the best specimens of the race survive; and to this occurrence is given the name of the "survival of the fittest," meaning the survival of those individuals best fitted to continue their own existence and to continue their species. A physical change in the country inhabited by a great multitude of individuals of a certain species, or by different species—for example, a change of climate—operates to make this struggle for existence still more severe, and the result would be that those individuals of the same species which could best adapt themselves to their new condition would tend to be preserved, as would the different species inhabiting the same country which could best maintain the struggle against other species. The improvement in the structure of the animals takes place, under this process of natural selection, in the following manner: The best individuals being preserved, the organs of which they make most use in the struggle for existence undergo development and slight modifications, favorable to the preservation of the individual, and these modifications are transmitted to their offspring. Here there comes in play a kind of collateral aid to which is given the name of "sexual selection," which is defined as a form of selection depending "not on a struggle for existence in relation to other organic beings or to external conditions, but on a struggle between individuals of one sex, generally the males, for the possession of the other sex."[23] "The result," continues Mr. Darwin, "is not death to the unsuccessful competitor, but few or no offspring. Sexual selection is, therefore, less rigorous than natural selection. Generally, the most vigorous males, those which are best fitted for their place in nature, will leave most progeny. But, in many cases, victory depends not so much on general vigor, as on having special weapons, confined to the male sex." As, by means of this warfare of sexual selection, the victor would always be allowed to breed, his courage and his special weapons of offense or defense, in their increased development, would descend to his offspring. Thus the improvement and modification induced by natural selection would be enhanced and transmitted by the sexual selection.[24]

In regard to the operation of the two kinds of selection in the evolution of man from a lower form of animal, we find the theory to be this: That organic beings with peculiar habits and structure have passed through transitions which have converted the primordial animal into one of totally different habits and structure; that, in these transitions, organs adapted to one condition and mode of life have become adapted to another; that such organs are homologous, and that in their widely varied uses they have been formed by transitional gradations, so that, for example, a floating apparatus, or swim-bladder, existing in a water-animal for one purpose—flotation—has become converted in the vertebrate animals into true lungs for the very different purpose of respiration. Thus, by ordinary generation, from an ancient and unknown prototype, not only have organs, by minute and successive transitions, become adapted to changed conditions of life, but the whole organism has become changed, and this has resulted in the production of an animal vastly superior to his ancient and unknown prototype; and yet to that prototype, of which we have no specimen and no record, are to be traced the germs of all the peculiarities of structure which we find in the perfect animals of different kinds that we thoroughly know, until we come to man, these successive results being brought about by the two kinds of selection—natural and sexual.

There can be no better illustration of the character of Mr. Darwin's theory than that to which he resorts when he means to carry it to its most startling length, while he candidly admits that he has felt the difficulty of this application of it far too keenly to be surprised at the hesitation of others. This illustration is the eye. Here he very justly says it is indispensable that reason should conquer imagination; but on which side of the question reason or imagination is most employed might, perhaps, be doubtful. Mr. Darwin's hypothesis concerning the eye begins with the fact that in the highest division of the animal kingdom, the vertebrata, we can start from an eye so simple that it consists, as in the lancelet,[25] of a little sack of transparent skin, furnished with a nerve, and lined with pigment, but destitute of any other apparatus. From this prototype of a visual organ, up to the marvelous construction of the eye of man or of the eagle, he supposes that extremely slight and gradual modifications have led, by the operation of natural and sexual selection; and by way of illustrating this development, he compares the formation of the eye to the formation of the telescope. "It is scarcely possible to avoid comparing the eye with a telescope. We know that this instrument has been perfected by the long-continued efforts of the highest human intellects, and we naturally infer that the eye has been formed by a somewhat analogous process. But may not this inference be presumptuous? Have we any right to assume that the Creator works by intellectual powers like those of man? If we must compare the eye to an optical instrument, we ought, in imagination, to take a thick layer of transparent tissue, with spaces filled with fluid, and with a nerve sensitive to light beneath, and then suppose every part of this layer to be continually changing slowly in density, so as to separate into layers of different densities and thickness, placed at different distances from each other, and with the surface of each layer slowly changing in form. Further, we must suppose that there is a power, represented by natural selection or the survival of the fittest, always watching each slight alteration in the transparent layers, and carefully preserving each which, under varied circumstances, in any way or in any degree, tends to produce a distincter image. We must suppose each new state of the instrument to be multiplied by the million, each to be preserved until a better one is produced, and then the old ones to be all destroyed. In living bodies variations will cause the slight alterations, generation will multiply them almost infinitely, and natural selection will pick out with unerring skill each improvement. Let this process go on for millions of years, and during each year on millions of individuals of many kinds, and may we not believe that a living optical instrument might thus be formed as superior to one of glass as the works of the Creator are to those of man?"[26]

It might have occurred to the very learned naturalist that the formation of a mechanical instrument by the hand of man, guided by his intellect, admits of varieties of that instrument for different purposes, as products of an intelligent will. Different kinds of telescopes for different uses have been produced, not by destroying the poorer ones and preserving the better ones, but by a special and intentional adaptation of the structure to special uses, until an instrument is made which will dissolve the nebulæ of the milky way, and bring within the reach of our vision heavenly bodies of the existence of which we had no previous knowledge. Why may not the same intelligent and intentional formation of the human eye, as a special structure adapted to the special conditions of such an animal as man, have been the direct work of the Creator, just as the lowest visual organ—that of such a creature as the lancelet—was specially made for the conditions of its existence? Why resort to the theory that all the intermediate varieties of the eye have grown successively out of the lowest form of such an organ by transitional grades of which we can not trace the series, when the probabilities concerning the varieties of this organ of which we have any knowledge are so strongly on the side of a special and intentional adaptation of each one to the circumstances of the animal to which it has been given? As a question of power in the Creator, either method of action was of course just as competent as the other. As a question of which was his probable method, the case is very different; for we know comparatively very little of the modifications produced by such causes as natural or even sexual selection, while we may, without presumption, assume that we know much more about the purposes of special adaptation to special conditions, which an omnipotent Creator may have designed and effected. But this is a digression, and also an anticipation of the argument.

To state the pedigree of man according to the Darwinian theory, we must begin with an aquatic animal as the early progenitor of all the vertebrata. This animal existing, it is assumed, "in the dim obscurity of the past," was provided with branchiæ or gills, or organs for respiration in water, with the two sexes united in the same individual, but with the most important organs of the body, such as the brain and heart, imperfectly or not at all developed. From this fish-like animal, or from some of its fish descendants, there was developed an amphibious creature, with the sexes distinct. Rising from the amphibians, through a long line of diversified forms, we come to an ancient marsupial animal, an order in which the young are born in a very incomplete state of development, and carried by the mother, while sucking, in a ventral pouch.[27] From the marsupials came the quadrumana[28] and all the higher mammals.[29] Among these mammals there was, it is supposed, a hairy, tailed quadruped, probably arboreal in its habits, from which man is descended. It was an inhabitant of the Old World. It branched into the lemuridæ, a group of four-handed animals, distinct from the monkeys, and resembling the insectivorous quadrupeds in some of their characters and habits;[30] and from these came the simiadæ, of which there were two great stems—the New World and Old World monkeys. "From the latter, at a remote period, man, the wonder and glory of the universe, proceeded."[31]

The reader must now, in order to do justice to this theory, imagine a lapse of time, from the period of the existence of the aquatic progenitor of all the vertebrata, to be counted by millions of years, or by any figures that will represent to the mind the most conceivable distance between a past and a present epoch. Through this enormous stretch of centuries, in order to give scope to the operation of the laws of natural and sexual selection, we must suppose the struggle for existence to be going on among the individuals of the same species, and among different species inhabiting the same country, and the sexual selection among the individuals of the same species to be perpetually transmitting to offspring the improved and more developed organs and powers induced by natural selection; so that in the countless sequence of generations there are evolved animals that are so widely different from their remote progenitors that in classifying them we find them to be new species, endowed with a power of reproducing their own type, and similarly capable, it would seem, of still further development into even higher types in the long-distant future.

I know not how it may appear to others, but to me the parallelism between the Platonic and the Darwinian theory is very striking. Both speculators assume the existence of a Supreme Intelligence and Power, presiding over the creation of animals which are to inhabit this earth. Behind the celestial or primitive gods the Greek philosopher places the Demiurgus, to whom the gods stand in the relation of ministers or servants to execute his will. The modern naturalist assumes the existence of the Omnipotent God; and although he does not directly personify the laws of natural and sexual selection which the Omnipotent power has made to operate in nature, they perform an office in the transitional gradations through which the animals are successively developed, that very closely resembles the office performed by the gods of Plato's system in providing the modifications of structure which the animals undergo. In the two processes the one is the reversed complement of the other. Plato begins with the formation of an animal of a very exalted type, and by successive degradations, induced by the failure of the animal to live up to the high standard of its rational existence, he supposes a descent into lower and still lower forms, the gods all the while providing a new structure for each successive lower form, until we reach the shell-fish fixed on the earth beneath the water. Darwin begins with the lowest form of animated organization, and by successive gradations induced by the struggle of the animal to maintain its existence, he supposes an ascent into higher and still higher forms, the laws of natural and sexual selection operating to develop a new structure for each successive higher form, until we reach man, "the wonder and glory of the universe," an animal whose immediate ancestor was the same as the monkey's, and whose remote progenitor was an aquatic creature breathing by gills and floating by a swim-bladder.

Nor had Plato less of probability to support his theory than Darwin had to support his. The Greek philosopher might have adduced the constant spectacle of men debasing their habits and even their physical appearance into a resemblance to the brutes. He might have suggested, and he does suggest, how the degrading tendencies of the lower appetites and the ravages of disease drag down the human frame from its erect carriage and its commanding power over matter to an approximation with the condition of the inferior animals. He might have adduced innumerable proofs of the loss of reason, or rationality, through successive generations of men, brought about by the transmission of both appetites and physical malformation from parents to children. He might have compared one of his Athenian fellow-citizens of the higher class with the lowest savage known throughout all the regions accessible to an observer of his day and country. He might have portrayed the one as a being preserving his physical organization in the highest state of perfection by gymnastic exercises, by a well-chosen diet, by observance of all the conditions of health, by the aid of the highest medical skill known to the age; cultivating his mind by philosophy, practicing every public and private virtue as they were understood among a people of rare refinement, and adorning his race by an exhibition of the highest qualities that were then attainable. All these qualities, physical, mental, and moral, Plato might have shown were transmissible in some degree, and in a good degree were actually transmitted from sire to son. Turning to the other picture, and comparing "Hyperion to the satyr," he might have shown that the lowest savage, in those physical points of structure which were best adapted to his animal preservation as an inhabitant of the wildest portion of the earth, had retained those which made him more nearly resemble the brute inhabitants of the same region, and that in his intellectual and moral qualities the resemblance between him and his Athenian contemporary was almost wholly lost. Intermediate between these extreme specimens of the human race, why could not Plato have found with great probability, and often with actual proof, successive degradations of structure and uses of organs, just as well supported by facts, or analogies, or hypotheses, as are Mr. Darwin's successive elevations from a lower to a higher animal? If Plato had known as much about the animal kingdom as is now known, he could have arrayed the same facts in support of his theory, by an argument as powerful as that which now supports the doctrine of evolution.

Nay, it is certain that Plato's attention was drawn to some of these facts, and that he makes use of them in a way that is as legitimately a probable occurrence as any use that is made of them at the present day. For example, he was struck with the existence of what in scientific parlance are called "rudiments," a term that is employed to describe an organ or part which appears to have no special use where it is found in one animal, but which, in a more developed or in a diversified condition, has an obvious use in another animal. Thus, he tells us that the gods, with a long-sighted providence, introduced a sketch or rudiment of nails into the earliest organization of man, foreseeing that the lower animals would be produced from the degeneration of man, and that to them claws and nails would be absolutely indispensable.[32] In the same way, he seems to regard hair as a rudiment, relatively speaking; for while its use on different parts of the body of man, or even on the head, is not very apparent, its use to the lower animals is very obvious. Why, then, is it not just as rational, and just as much in accordance with proper scientific reasoning, to suppose those parts of animal structure which are called "rudiments" to have been introduced as mere sketches in the organization of a very high animal, and then to have been developed into special uses in lower animals produced by the degeneration of the higher, as it is to suppose that they were developed in full activity and use in the lower animals, but sank into the condition of useless or comparatively useless appendages as the higher animal was evolved out of the lower by a process of elevation? The modern naturalist of the evolution school will doubtless say that "rudiments" in the human structure, for which there is no assignable use that can be observed, are not to be accounted for as sketches from which Nature was to work, in finding for them a use in some other animal in a developed and practically important condition; that, to the extent to which such things are found in man, they are proofs of his cognate relations to the lower animals, in which they have a palpable use; and that the gradations by which they have proceeded from practical and important uses in the lower animals, until they have become mere useless or comparatively useless sketches in the human structure, are among the proofs of the descent of man from the lower animals which had a use for such things. I shall endeavor hereafter to examine the argument that is derived from "rudiments" more closely. At present, the point which I suggest to the mind of the reader arises in the parallel between the Platonic and the Darwinian theory of the origin of the different species of animals. I ask, why is it not just as probably a true hypothesis to suppose that man was first created with these rudimentary sketches in his organization, and that they became useful appendages in the lower animals, into which man became degenerated, as it is to suppose that these parts existed in full development, activity, and practical use in the lower animals, out of whom man was generated, and that in man they lost their utility and became relatively mere rudiments? To my mind, neither theory has the requisite amount of probability in its favor compared with the probability of special creations; but I can see as much probability in the Platonic as in the Darwinian explanation, and a strong parallelism between them.