This argument would have left no escape to the most decided adversary of the Darwinian view, if its first proposition had been susceptible of demonstration. But Mr. Darwin, seeing the utter impossibility of demonstrating it, and yet being unable to dispense with it, resorted to the ordinary trick of his school, which consists in assuming latently what they dare not openly maintain; and thus he turned the whole attention of his reader to the second proposition, which had no need of demonstration, as it was not questioned by instructed men. Thus the twenty pages of physiologic lore with which Mr. Darwin in this chapter distracts and amuses his readers may be styled, in a logical point of view, a prolonged ignoratio elenchi—an effort to prove that which is conceded instead of that which is denied—a blunder into which men of science of the modern type are sure to fall when they presume to meddle with matters above their reach.
There is one sense only in which it may be affirmed that the similarity of bodily structure in men and lower animals proves their common origin, and it is this: that men and animals have been made by the same Creator on a similar ideal type of homogeneous organic arrangements; in other terms, that their organic similarity proves them to be the work of the same Maker. Man was destined to live on this earth among other inferior animals and surrounded by like conditions. His animal life was therefore to be dependent on similar means of support, exposed to similar influences, and subject to similar needs. It is not surprising, then, that he should have received from a wise Creator an organic constitution similar to that of the inferior creatures that were placed around him. This fully accounts for the similarity of the human organism with that of other mammals. But to say that because the bodily structure of man is similar to that of the ape, therefore man is the descendant of the ape, is as nonsensical as to say that because the bodily structure of the ape is similar to that of man, therefore the ape is the descendant of man. How was it possible for Mr. Darwin to lay down such an absurd principle, and not foresee how easily it might be turned against his own conclusion?
Thus the argument drawn from the similarity of bodily structure is a mere delusion. It avails nothing to say that man is liable to receive from the lower animals, and to communicate to them, certain diseases, as hydrophobia, variola, the glanders, syphilis, cholera, herpes, etc. This fact, says Mr. Darwin, “proves the similarity of their tissues and blood, both in minute structure and composition, far more plainly than does their comparison under the best microscope or by the aid of the best chemical analysis.” But this is a mistake; for the evidence afforded by the microscope as to existing diversities cannot be negatived by any guesses of ours respecting the communication of diseases and its conditions; it being evident that what is obscure and mysterious is not calculated to weaken the certitude of a fact which we see with our own eyes. Nor does it matter that “medicines produce the same effect on them [monkeys] as on us,” or that many monkeys “have a strong taste for tea, coffee, and spirituous liquors,” or even that a certain monkey “smoked tobacco with pleasure” in Mr. Darwin’s presence. These and other details of the same nature may be interesting, but they are no indication of a common origin, except in the sense which we have pointed out—viz., that they are the work of the same Maker.
But, says Mr. Darwin, “the homological construction of the whole frame in the members of the same class is intelligible, if we admit their descent from a common progenitor, together with their subsequent adaptation to diversified conditions. On any other view the similarity of pattern between the hand of a man or monkey, the foot of a horse, the flipper of a seal, the wing of a bat, etc., is utterly inexplicable. It is no scientific explanation to assert that they have all been formed on the same ideal plan.” These words, which occur at the end of the chapter we are examining, show how little Mr. Darwin understands the duty of his position as author of a new theory. To say that an explanation is not scientific is a very poor excuse for setting it aside. Science, if not perverted, is an excellent thing, but it does not profess to give an explanation of every subject we may think of. Its range is co-extensive with the material world, but only with respect to matter and its modifications as known by observation and experiment. This means that there are numberless things about which science is altogether incompetent to speak, because such things do not fall under observation and experiment. To pretend, therefore, that an explanation which is not scientific has no claim to be heeded by a man of science, is like pretending that a man of science, as such, must remain in blissful ignorance of everything which transcends experiment and observation. Will Mr. Darwin reject historical explanations of historical events, philosophical explanations of philosophical conclusions, mathematical explanations of mathematical questions? The origin of things is not a scientific but a philosophic problem. Science cannot speak of creation, of which it can have no experimental knowledge; it gives it up to the philosopher and the theologian, who alone know the grounds on which it must be demonstrated. The question, then, whether mammals have all been formed on the same ideal plan, is not scientific, and therefore it needs no scientific explanation. The plea that the explanation is not scientific might be held valid, if Mr. Darwin had humbly acknowledged his inability to rise above matter, and his incompetency to give a judgment in philosophic matters; but his disregard of the explanation shows that, when he calls it not scientific, he desires his reader to believe that it is anti-scientific or irreconcilable with science; and this is as absurd as if he pretended that reason and science destroy one another.
On the other hand, what shall we say of the pretended “scientific” explanation offered by Mr. Darwin? “The homological construction of the whole frame in the members of the same class is intelligible, if we admit their descent from a common progenitor.” Is this appeal to a common progenitor a scientific explanation of the fact in question? If a common progenitor accounts scientifically for the fact, why should not a common Creator account scientifically for it? Science—that is, Mr. Darwin’s science—does not know a common Creator; it knows even less of a common progenitor; and yet it sets up the latter to exclude the former, and boasts that its gratuitous and degrading hypothesis is a “scientific” explanation! Yet all true scientists aver that no instance has ever been found of a transition from one species to another; philosophers go even further, and show that such a transition is against nature. Hence Mr. Darwin’s hypothesis, far from being scientific, contradicts science and philosophy, observation and experiment, reason and fact. The descent from a common progenitor, even if it made “intelligible” the similarity of different mammals, would still be unscientific. The ancients accounted for the movement of the heavenly bodies by putting them under the control of intellectual agents. This hypothesis made the astronomical phenomena intelligible. The fall of heavy bodies was accounted for by assuming that all such bodies had a natural intrinsic tendency to a central point. This hypothesis, too, made the fall of bodies intelligible. Even in modern physics a number of hypotheses have been proposed regarding light, magnetism, electricity, chemical changes, etc., to make phenomena intelligible. But hypotheses, however satisfactory at first, are soon discarded when a deeper study of the facts reveals new features and new relations for which such hypotheses cannot account. This is why the hypothesis of the descent of all mammals from a common progenitor, even if it seems to make their homological construction intelligible in a manner, must be rejected. For in every species of mammals we find features for which the hypothesis cannot account, and relations of genetic opposition by which the hypothesis is reduced to nothing.
Mr. Darwin says that, “on any other view, the similarity of pattern between the hand of a man or monkey, the foot of a horse, the flipper of a seal, the wing of a bat, etc., is utterly inexplicable.” We do not see any great similarity between the hand of a man and the foot of a horse or the flipper of a seal, etc. We would rather say, with Mr. Darwin’s permission, that we see in all such organs a great dissimilarity. Each of them has a special adaptation to a special end, and each of them is constructed on a different specific pattern. Their similarity is therefore generic, not specific; and, accordingly, each species must have its own distinct progenitors. We might make other remarks, but we are afraid that we have already taxed the patience of the reader to a greater extent than the case requires; and therefore we will now pass to the second argument of the author.
This second argument is drawn from the consideration of the embryonic development. “Man,” says Mr. Darwin, “is developed from an ovule about the 125th of an inch in diameter, which differs in no respect from the ovules of other animals.” This is a very reckless assertion. For how does Mr. Darwin happen to know that the human ovule “differs in no respect” from the ovules of other animals? When a man of science lays down an assertion as the groundwork of his doctrine, he must be able to show that the assertion is true. Hence we are entitled to ask on what foundation our great scientist can maintain his proposition. Will he appeal to the microscope? Probably he will, but to no purpose; for he has just declared, as we have seen, that the best microscope does not reveal everything with sufficient distinction. On the other hand, if he resorts to the mode of reasoning which he has just employed while speaking of diseases—that is, if he argues from the effects to the causes—he cannot but defeat himself; for, as similarity of diseases was, in his judgment, a proof of similar organic structure, so now the dissimilarity of the final development of two ovules will be a proof that the two ovules are really dissimilar. One ovule constantly develops into a monkey, another constantly develops into a dog, and a third constantly develops into a man. Is it conceivable that the three ovules are identically the same, so as to “differ in no respect”? We do not know what Mr. Darwin will reply. At any rate he cannot reply on scientific grounds; for science neither knows the intimate constitution of the ovules, nor is it likely ever to know it, as the primordial organic molecules baffle the best microscopic investigations.
“The embryo itself,” he adds, “at a very early period can hardly be distinguished from that of other members of the vertebrate kingdom.... At a somewhat later period, when the extremities are developed, ‘the feet of lizards and mammals,’ as the illustrious Von Baer remarks, ‘the wings and feet of birds, no less than the hands and feet of man, all arise from the same fundamental form.’ It is, says Prof. Huxley, ‘quite in the later stages of development that the young human being presents marked differences from the young ape.’”
If these assertions and quotations are intended as a proof that the human ovule “differs in no respect” from the ovules of lower animals, we must confess that our advanced scientific thinkers are endowed with a wonderful power of blinding themselves. We have two ovules: the one develops into hands and feet; the other develops into wings and feathers; and yet we are told that they are both “the same fundamental form”! What is the fundamental form? Who has seen it? We are sure that neither Prof. Huxley nor the illustrious Von Baer has had the privilege of inspecting and determining the proper form of the mysterious organism known under the name of ovule. Much less have they, or has Mr. Darwin, discerned what is fundamental and what is not in its constitution. They are, therefore, not more competent to judge of the fundamental sameness of two ovules than is the blind to judge of colors; and their view, as founded on nothing but presumption and ignorance, must be considered altogether unscientific.
The same view is also, as we have already shown, eminently unphilosophic. If two ovules are essentially the same and “differ in no respect” from one another, what is it that causes them invariably to develop into different specific organisms? Does a constant difference in the effects countenance the idea that they proceed from identical causes? It is evident that a theory which resorts to such absurdities for its support has no claim to be accepted, or even tolerated, by lovers of reason and truth. The very boldness of its affirmations, its air of dogmatism, its allegation of partisan authorities, and its contempt of fundamental principles prove it to be nothing but a flippant attempt at imposition.