Chapter III (2)

There are several other alleged homologues or rudiments which are supposed to connect man with the lower animals, but which, whatever may be the resemblances, it is not necessary to discuss in detail, because there is one consideration at least which applies to the whole of this class of proofs, and to that I now pass. The three great classes of facts on which the whole argument rests, viewing man as an animal and omitting all reference to his intellect, are the resemblances of his bodily structure to that of the other mammals, the similarity between his embryonic development and theirs, and the rudiments. I reserve for separate discussion the counter-proof which may be derived from the nature of the human mind, and the special adaptation of the human structure to become the temporary residence and instrument of a spiritual and immortal being.

"It is," says Mr. Darwin, "no scientific explanation to assert that they have all [man and the other animals of the mammalian class] been formed on the same ideal plan."[51] The similarity of pattern is pronounced "utterly inexplicable" upon any other hypothesis than that all these animals are descended from a common progenitor, and that they have become what they are by subsequent adaptation to diversified conditions. I may incur some risk in undertaking to suggest what is a "scientific" explanation. Certainly I do not propose to "assert" anything. But I will endeavor to keep within the bounds of what I suppose to be science. I take that to be a scientific explanation which, embracing the important facts of natural history as the groundwork of the reasoning, undertakes to show the rationality of one hypothesis that differs from another, when the question is, Which has the greater amount of probability in its favor?

All correct reasoning on this subject of man's descent as an animal begins, I presume, with the postulate of an Infinite Creator, having under his power all the elements and forms of matter, organized and unorganized, animate and inanimate. There is no fundamental difference of opinion on this point, as I understand, between some of the evolutionists and their opponents.[52] Omnipotence, boundless choice of means and ends, illimitable wisdom, a benevolence that can not fail and can not err, are the conceded attributes of the being who is supposed to preside over the universe; and, however difficult it may be for us to express a conception of infinite power and infinite wisdom, as it is to describe infinite space and duration, we know what we mean to assume when we speak or think of faculties that are without limit, and of moral qualities that are subject to no imperfection. It is true that we have no means of forming an idea of superhuman and infinite power but by a comparison of our own limited faculties with those which we assume to belong to an eternal and infinite God. But the nature of our own limited powers teaches us that there may be powers that are as far above ours as the heavens are above the earth, as the endless realms of space stretch beyond and forever beyond any measurable distance, as eternity stretches beyond and forever beyond all measurable time. At all events, the postulate of an infinite God is the one common starting-point for the scientists of the evolution school and those who accept their doctrine, and for those who dissent from it. If I did not assume this, I could not go one step further, for without it there could not be a basis for any reasoning on the subject that would lead anywhere but to the conclusion that all that exists came by blind chance. This conclusion is rejected alike by the scientists, whose views I am now examining, and by those who differ from them.

In the economy of Nature, which is but another term for the economy of the Omnipotent Creator, there is no waste of power, as there is no abstention from the exercise of power, where its exertions are needed to accomplish an end. By this I mean that when a general plan of construction is found carried out through a variety of organizations, the rational inference is that so much power has been exerted as was needful to accomplish in each organization the objects that are common to all of them, and that no more power has been used in that direction. But where a special adaptation in some one variety of the same class of constructions is needful to accomplish an object peculiar to a new variety, the necessary amount of power never fails to be exerted. A study of the animal kingdom reveals this great truth, as palpably as a study of the products of human skill reveals the fact that man, from the imperfection of his faculties, is constantly exerting more or less power than was needful in his efforts to produce a new variety in his mechanical constructions. Experience and accumulated knowledge enable us to carry a general plan of construction through a considerable group of mechanical forms; but it is when we endeavor to vary the principle of construction so as to produce a new and special mode of operation, that we either waste power in repeating the general plan or fail to exercise the amount of power necessary to adapt the general plan to the introduction of the special object at which we are aiming. Our success in making such adaptations is often wonderful, but our failures evince that our imperfect faculties do not always enable us to accomplish the necessary adaptations of the general plan of construction to the special objects which we wish to attain. To the Infinite Creator, all such difficulties are unknown. He neither wastes power by new plans that are unnecessary, nor makes "vain repetitions," nor fails to exert the requisite amount of power and wisdom in the introduction of new and special contrivances which he ingrafts upon or superadds to the general plan, and which he has devised for the accomplishment of a new object. With a boundless choice of means and ends, with a skill that can not err, with a prescience that sees the end from the first conception of the design, he can repeat the general plan throughout any variety of constructions without any waste of power, and can introduce the new adaptations or contrivances which are to constitute a new construction, by the exercise of all the power that is required to accomplish a special object. Whether we are to suppose that he does this by the establishment of certain laws which he leaves to operate within prescribed limits, or does it by special creations proceeding from direct and specific exertions of his will, the question of his power to employ the one method or the other remains always the same. The question of which was his probable method depends upon the force of evidence; and upon this question we must allow great weight to the fact which all Nature discloses, namely, that the Creator does not waste power by making new plans of construction where an existing plan may be usefully repeated, and that he does not fail to exercise the necessary power when he wishes to add to the general plan of construction a new and special organism for a particular purpose.

Is there anything presumptuous in thus speaking of the determination and purposes of the Omnipotent Creator? We have his existence and infinite attributes conceded as the basis of all sound reasoning on his works. Why then should we not infer his purposes and his acts from his works? Why should we not attribute to him a special design, when we can not examine his works without inferring such special design, unless we conclude that the most amazing and peculiar constructions grew up under the operation of causes of which we have no sufficient proof, and in the supposed result of which there are admitted chasms that can not be bridged over?

To return now to the resemblance between the bodily structure of man and that of his supposed progenitors. The assertion is that a repetition of the same general plan of construction throughout a class of animals can only be explained upon the hypothesis of their descent from a common progenitor. They are, it is claimed, co-descendants from some one ancient animal; and however they may differ from each other, in all these co-descendants from that animal we find the same general plan of construction, the same ideal model repeated. Among the whole class of the higher mammals, we have skeletons, muscles, nerves, blood-vessels, internal viscera, organs, that closely correspond. What does this prove but that there was no waste of power, because there was no necessity in making man, for the formation of a general plan of construction different in these particulars from that which was employed in making the monkey, the bat, or the seal? The similarity of pattern between the hand of a man or a monkey, the foot of a horse, the flipper of a seal, or the wing of a bat, is pronounced "utterly inexplicable" upon any hypothesis but that of descent from a common progenitor. But why is not this sameness of ideal plan just as consistent with the hypothesis that the same ideal plan would answer for the human hand or the hand of an ape, the foot of the horse, the flipper of the seal, or the wing of the bat?[53] It is when you pass from such resemblances and come to the special contrivances which separate one animal from another by a broad line of demarkation, that you are to look for the adaptation of special contrivances to repetitions of the same ideal model through the varying species. Take, for example, the introduction among the mammals of the placental system of reproduction, parturition, and subsequent nourishment of the young, combined with the nourishment of the fœtus while it continues in the body of the mother. This system would require no material variation from the general plan of construction that is common to the different mammals of this class in respect to the parts where the resemblances are kept up throughout the series, such as those of the skeleton, muscles, nerves, viscera, and other organs that are found in all of them. But for the introduction of this peculiar system of reproduction and continuation of the species, there was needful a special and most extraordinary contrivance. If such a contrivance or anything like it had been produced by human skill, and been introduced into a mechanical structure, we should not hesitate to say that there had been an invention of a most special character. When you follow this system through the different animals in which it is found operating, and find that the period of gestation and of suckling is varied for each of them, that for each there is the necessary modification of trunk, situation of the organs, assimilation of food and formation of milk, and many other peculiarities, what are you to conclude but that there has been an adaptation of a new system to a general plan of construction, and that while the latter remains substantially the same, it has had ingrafted upon or incorporated with it a most singular contrivance, so original, comprehensive, and flexible, that its characteristic principle admits of the most exact working in animals that are as far asunder as man and the horse, or as the horse and the seal, or as the seal and the bat?

The resemblances between the embryonic development of man and the other mammals present another instance of the constantly occurring fact that there has been no waste of power on the one hand, and on the other no failure to exert the amount of power requisite to produce a new variation of the general principle. There is no more logical force in the hypothesis of a common progenitor, in order to account for these resemblances, than there is in the hypothesis that the general system of embryonic development was first devised, and that it was then varied in each distinct animal according to the requirements of its special construction. Upon the latter supposition, there would be resemblances to a certain stage, and then there would follow the departures which we have no difficulty in tracing. Upon the former supposition we should expect to find, what we actually do find, that it is very difficult, if not impossible, to assign any reason for the departures, or to suggest how it has happened that one animal is so absolutely distinct from another. Thus, to begin with the embryo itself, and to trace it through its stages of development, we find that in man it can hardly be distinguished from that of other members of the vertebrate kingdom. This we should expect to be the case after we have learned the great fact that Nature operates upon a uniform principle up to the point where variations and departures are to supervene. The system of embryonic development being devised to operate in parallel lines through all the placental mammals until the lines should begin to depart from each other so as to result in animals of different species, would necessarily show strong resemblances of structure until the departures supervened. There would be, in other words, a strong illustration of the truth that in the Divine economy there is no waste of power. But when the stage is reached at which the departures may be noted, and the lines diverge into the production of organized beings differing widely from each other, we reach an equally striking illustration of the corresponding truth that the amount of power necessary to produce very different results never fails to be put forth. There is no good reason why this latter exertion of power should not be attributed to special design just as logically and rationally as we must attribute to intentional purpose and infinite skill the general system of embryonic development which has been made for the whole class of the placental mammals. While, therefore, we may accept as a fact Prof. Huxley's statement on this branch of comparative anatomy, we are under no necessity to accept his conclusion. To the question whether man originates in a different way from a dog, bird, frog, or fish, this anatomist answers, as already quoted: "The reply is not doubtful for a moment; without question, the mode of origin and the early stages of the development of man are identical with those of the animals immediately below him in the scale; without a doubt, in these respects he is far nearer to apes than apes are to the dog." This refers, of course, to the parallelism that obtains in the early stages of the embryonic development. It necessarily implies, at later stages, diverging lines, which depart more or less from each other, and thus we have between the ape and the man a nearer approach than we have between the ape and the dog. But how does this displace, or tend to displace, the hypothesis of a general system of embryonic development for all animals of a certain class, and an intentional and special variation of that system so as to produce different species of animals? The identity between the mode of origin and the early stages of the development of man and those of the animals immediately below him in the scale, is strong proof of the applicability of the same general principle of development throughout all the animals of a certain class. The cessation of the parallelism at the diverging lines is equally strong proof of a design to create an animal differing as man does from the ape, or as the ape does from the dog. The argument that these three species are co-descendants from a common progenitor, viewing man simply as an animal, is at least no stronger than the argument which leads to the conclusion of special creations.

The same thing may be said of the liability of man to certain contagious or non-contagious diseases in common with some of the lower animals. That there is a similarity in the chemical composition of the blood of an entire class of animals, in the structure of their tissues and blood-vessels, so that they are subject to the same causes of inflammation or to the same parasites, is proof of a uniform plan of the fluids and the vascular system, or, in other words, it evinces that here, too, there has been in these respects no waste of power in forming the different animals of the same class. But trace back the supposed pedigree of the animals sharing this chemical composition of the blood, character of tissues, and vascular system, until you have passed through the amphibians and reached their supposed fish progenitors. Somewhere between the fishes and the higher mammals, you have not only a great change in the chemical composition of the blood-vessels and tissues, but an equally great change in the apparatus by which the blood is oxygenated.[54] How can these changes have been brought about without a new and intentional structure of the vessels and the apparatus for supplying the oxygen demanded for the continuation of life? How can we explain these changes by such agencies as the natural selection which is supposed to lead to the "survival of the fittest," and the sexual selection which is supposed to give to the best-appointed males of a given species the power to transmit to their offspring the new peculiarities which they have acquired through successive generations? Do not these changes show that there is a line of division which such agencies alone can not cross? Do they not clearly point to the exercise of the creative power in a special manner, and for special purposes? That power being once exercised, the new chemical composition and mechanical appliances being devised, the same "ideal plan" could be carried through a new class of animals by a repetition which is in accordance with the economy of Nature, and which an infinite power could adapt to the formation of animals, each of which was designed to perpetuate its own species and no other. Hence we should expect to find in the animals sharing in the same formation of the blood and the vascular system a corresponding process of healing the parts severed by a wound, and a continuous secretion from such vessels as have not been cut away; but we should not expect to find the stumps growing into a new and perfect part, to take the place of what has been removed by amputation.[55] We should expect to find the same drugs affecting different animals of the same class alike; and when the nervous system of a class of animals is upon the same general plan, we should expect to find them similarly affected by stimulants. But these resemblances do not militate very strongly against the hypothesis of special creations, when we consider that it is according to the universal economy of the Omnipotent Creator to employ the necessary, and no more than the necessary, power in originating a plan that may be applied to the formation of a distinct class of beings, and that his adaptations of this plan to further and specific constructions of beings belonging to a general class, but differing widely from each other, are among the strongest and plainest proofs of his infinite power and the nature of his methods.

In regard to the "rudiments" that are found in man, the theory of Mr. Darwin can be best stated in his own words: "In order to understand the existence of rudimentary organs, we have only to suppose that a former progenitor possessed the parts in question in a perfect state, and that under changed habits of life they became greatly reduced, either from simple disuse or through the natural selection of those individuals which were least encumbered with a superfluous part, aided by the other means previously indicated."[56] But, in order to do justice to this theory, it is necessary to repeat the description and operation of the supposed agencies of natural and sexual selection. Natural selection is an occurrence which takes place among the individuals of a certain species in the struggle for existence, whereby those who are best appointed secure the necessary supply of food, and the weaker or less active are either directly destroyed in the contest or perish for want of nourishment. The "fittest" having survived, they have the best chance of procreating their kind, and are likely to have the most progeny. To these individuals there comes in aid the sexual selection, which means chiefly the victory of the fittest males over their less fit competitors for the possession of the females. Whatever peculiarities of structure or development, or diminution of structure or development, these fittest males possess, they would transmit to their offspring. This tendency would be enhanced by the varying conditions of life through which the successive generations might have to pass; so that if the former progenitor possessed naturally an organ in a perfect state, but ceased to make use of it, and for thousands of generations its use went on diminishing, it would sink into the condition of a mere rudiment. Supposing this to be a partially true explanation of the modes in which organs become rudimentary, how does it militate against the idea of separate creations? We have "only to suppose" that the first men possessed, for example, the power of moving the skin all over their bodies by the contraction of certain muscles, and that their remote descendants lost it everywhere excepting in a few parts, where it remains in an efficient state, and that it has become varied in different individuals. The process by which organs become rudimentary is an hypothesis just as consistent with the separate creation of man as it is with his being a co-descendant from some lower animal whose descendants branched into men, apes, horses, seals, bats, etc.; for, on the supposition of the separate creation of all these different animals, each species might have been originally endowed with this power of muscular contraction of the skin, and in their descendants it might have been retained or varied or have become more or less rudimentary, according to its utility to the particular species. The truth is, that our own faculties of creation or construction, when we undertake to deal with matter and its properties, are so imperfect, and that which constitutes living organisms is so utterly beyond our reach, that we do not sufficiently remember how entirely it is within the compass of the infinite Power, which has given to matter all the properties that it possesses and has living organisms under its absolute control, to form a system of construction and operation for beings of entirely distinct characters, carrying it through each of them in parallel lines, or causing it to diverge into varying results with an economy that neither wastes the constructive power nor fails to exert it where it is needed. To argue that the presence of rudiments in different animals, in different comparative states of development or efficiency, or in a purely useless condition, can only be explained by a descent from some remote common progenitor, is what the logicians call a _non sequitur_. It overlooks the illimitable faculty of the creating Power, and disregards the great fact that such a power acts by an economy that is saving where uniformity will accomplish what is intended, that is profuse where variation is needful, and that can guide its own exertions of power, or its abstention from such exertions, by unerring wisdom, to the most varied and exact results.

I trust that by the use of the term "economy" in speaking of what is observable in the works of the Creator, I shall be understood as comprehending both the avoidance of unnecessary and the exertion of all necessary power. Of the degree of necessity in any exercise of a power which we suppose to be infinite, we can only judge by what we can see. If omnipotence and omniscience are to be predicated of the being who is supposed to preside over the universe, it is rational to conclude, from all that we can discover, that, in applying a uniform system of construction to different animals of a certain general class, he acted upon a principle that his unerring faculties enabled him to see was a comprehensive one; and that in producing variations of that system of construction that would result in adapting its uniformity to the varying conditions of the different species, he acted by the same boundless wisdom and power. If these postulates of the Divine attributes are conceded, rudiments do not by any means necessarily lead to the conclusion that all the animals of a certain class are co-descendants from some remote common progenitor, for they do not exclude the hypothesis that each distinct animal was formed upon a general plan of construction that could be applied throughout the class, but that it was varied according to the special conditions of its intended being. Organs or parts may thus have become more or less rudimentary without resorting to the supposition of a common progenitor for the whole class. That supposition, indeed, makes it necessary to assume that the infinite Creator fashioned some one animal, and then, abstaining from all work of further direct creation, left all the other animals to be evolved out of that one by the operation of secondary causes that fail even as a theory to account for what we see, and that can not be traced through any results that have yet been discovered. Wherever we pause in the ascending scale of the Darwinian descent of man, wherever we place the first special act of creative power, whether we put it at the fish-like animal of the most remote antiquity, and call that creature the original progenitor of all the vertebrata, or whether we suppose a special creation to have occurred at the introduction of the mammalian series, or anywhere else, we have to account for changes of system, new constructions, elaborately diversified forms, by the operation of agencies that were incapable of producing the results, if we are to judge of their capacity by anything that we have seen or known of their effects.

I will conclude this chapter by expressing as accurately as I can what has struck me as the excessive tendency of modern science to resolve everything into the operation of general laws, or into what we call secondary causes. I may be able to suggest nothing new upon this part of the subject, but I shall at least be able, I hope, to put my own mind in contact with that of the reader by explaining what has impressed me in the speculations of those who lay so much stress upon the potency of general laws to produce the results which we see in Nature. Of course, I do not question the great fact that the infinite Power acts by and through the uniform methods from which we are accustomed to infer what we call laws; which in physics is nothing but a deduction of regularity and system from that which we see to be perpetually and invariably happening. Now, I do not enter here into the question of the tendency of modern science to displace our religious ideas of a special Providence, by attributing everything in Nature to the operation of fixed laws of matter; or its tendency, in other words, to remove the infinite Being at a greater distance from us than that in which our religious feelings like to contemplate him. I am perfectly sensible that in truth the infinite God is just as near to us, when we regard him as acting by general laws and secondary causes, as when we believe him to be exercising a direct and special power. I am equally sensible that it is in the very nature of infinite power, wisdom, and benevolence to be able and willing to ordain uniform and fixed principles of action. That Power which gives to matter all its properties may well be supposed to have established uniformity and regularity of movements, forces, combinations, and qualities. How supremely consistent this uniformity and regularity are, with what stupendous accuracy they are kept forever in operation, we are more or less able to discern; and that benevolence which is believed to accompany the power may well be supposed to have intended that its intelligent and rational creatures should be able in some degree to discover and to avail themselves of these unvarying laws of the physical world. But are these laws to be supposed to be the only methods by which the infinite Will has ever acted? Is it to be assumed that, having settled and established these perpetual principles, on which matter, organized or unorganized, is to act, he leaves everything to their operation and abstains from all further exertion of his creative power for any special purpose? Has he given to these general laws a potency to produce, in and of themselves, all the results? In other words, has he affixed to their operation no limitations, or has he set bounds to them, and reserved to himself, by direct, specific, and occasional exercise of his will and power, for new purposes, to produce results for which the general laws were not ordained?

It is not necessary here to enter into the consideration of what are called "miracles." These, in their true meaning, are special interpositions, which the Divine Power is supposed to make, by a suspension or interruption of the established laws of Nature; and, whatever may be the grounds of our belief or our unbelief in such occurrences, they are not exercises of power such as those which are supposed to take place in special creations of new beings. That the hypothesis of special creations of new beings involves no interruption or displacement of the fixed laws of Nature, is quite manifest.

NOTE A.

NOTE ON AMPUTATION, OR SEVERANCE OF PARTS.--As Mr. Darwin attached some importance to a fact which he asserted respecting the efforts of Nature to restore a part of an organism which has been severed by amputation, I think it well to quote his statement, and to point out what I believe to be an inaccuracy. His statement is this: "His [man's] wounds are repaired by the same process of healing, and the stumps left after the amputation of his limbs, especially during an early embryonic period, occasionally possess some power of regeneration, as in the lowest animals." It is not quite apparent what he means by amputation during an early embryonic period. If he is to be understood as referring to a case of complete severance of any part of an embryo before birth, it has not been demonstrated that such a severance has been followed by a successful effort of Nature to replace the severed part; and it is difficult to understand how there could be such an amputation during embryonic life without destroying the life of the embryo; or, if the severed part were one of the extremities, how there could be a new extremity formed. In such a case, if life continued and birth were to take place, the animal must be born in an imperfect state. In regard to amputations taking place at any time after birth, if the expression "some power of regeneration" means to imply a new formation to take the place of the severed part, the assertion is not correct. What occurs in such cases may be illustrated by the very common accident of the severance of the end of a human finger at the root of the nail. If the incision is far enough back to remove the whole of the vessels which secrete the horny substance that forms the nail, there will be no after growth of anything resembling a nail. If some of those vessels are left in the stump, there will be continuous secretion and deposit of the horny substance, which may go so far as to form a crude resemblance to a nail. But if all the vessels which constitute the means of perpetuating a perfect nail are not left in their normal number and action, there can be no such thing as the formation of a new nail. Whether it is correct to speak of the imperfect continuation of a few of the vessels to secrete the substance which it is their normal function to secrete, as a "power of regeneration," is more than doubtful, if by such a power is meant a power to make a new and complete structure to take the place of the structure that has been cut away. It is nothing more than the continued action of a few vessels, less in number than the normal system required for the continued growth and renewal of the part in question. The abortive product in such cases looks like an unsuccessful effort of Nature to make a new structure in place of the old one; but it is not in reality such an effort. The fact that the same thing occurs, in just the same way and to a corresponding extent, in different animals, has no tendency to prove anything excepting that these different animals share the same general system of secreting vessels for the formation and perpetuation of the several parts of their structures. It has no tendency to prove that they are co-descendants from a common ancestral stock, for on the hypothesis of their special and independent creation a common system of secreting vessels would be entirely consistent with their peculiar and special constructions.

FOOTNOTES:

[35] "Descent of Man," pp. 164, 609.

[36] "Descent of Man," p. 159.

[37] "Origin of Species," p. 148.

[38] "Descent of Man," p. 165.

[39] "Descent of Man," p. 158.

[40] "Descent of Man," p. 155.

[41] Ibid.

[42] "Descent of Man," pp. 156, 157.

[43] Ibid., p. 156.

[44] "Descent of Man," p. 156.

[45] "Descent of Man," p. 6.

[46] Ibid., p. 8.

[47] Ibid.

[48] "Descent of Man," pp. 9, 10, quoting Huxley, "Man's Place in Nature," p. 65.

[49] "Descent of Man," p. 11 _et seq._

[50] Ibid.

[51] "Descent of Man," p. 24. Consult Mr. Darwin's note on Prof. Bianconi's explanation of homologous structures upon mechanical principles, in accordance with their uses.

[52] Mr. Herbert Spencer's peculiar views are not here included in the discussion, but they will be considered hereafter.

[53] It is immaterial, of course, in this discussion, whether the formation of man preceded that of the other animals, according to the Platonic idea, or whether, as in the account given in the book of Genesis, the other animals were first formed. So far as an ideal plan entered into all of them, that plan may have been devised for and first applied to any part of the series, and then varied accordingly.

[54] The popular terms--"fish" and "flesh"--present to the mind the most vivid idea of this change from the characteristic substance of one of these animals to that of another.

[55] See the note on amputation, or severance of parts, at the end of this chapter.

[56] "Descent of Man," p. 25.