« ПредыдущаяПродолжить »
of man and his history,' and this implies that man must be included with other organic beings in any general conclusion respecting the manner of his appearance on this earth."
Nay, Darwin himself has now gone further, and, to the terror of all who can scarce imagine man except as created shaven and armed with a book on etiquette, he has sketched a certainly not flattering, and perhaps in many points not correct, portrait of our presumptive ancestors in the phase of dawning humanity.
Before we seriously discuss this serious subject, we will take leave to quote a more superficial verdict given by a clever essayist. "Let us suppose, merely as a joke, that Nature, which we see everywhere advancing from the most simple to the complex, from the lower to the higher, had not suddenly waived this law in the presence of man; that she had not suddenly given up her evolution for his sake; that she had not suddenly begun in him a new creation; but that here, as elsewhere, she had proceeded quietly, gradually, naturally, and that man were thus nothing more than the last link of the interminable series of animals, nothing more than a 'developed ape.' The first thought that would then obtrude itself upon us, would be that the facts were not altered in the slightest degree; that man would remain as he is, with the same shape, the same face, the same gait, the same gestures, the same dispositions, powers, feelings, thoughts, and with the same dominion over the apes as heretofore. This is very simple, very self-evident, but also very important. For it confers on himon man—the powerful sensation that, as he now is, he is a being of a quite peculiar kind, very different from
even the most kindred creature; and, moreover, that this peculiar nature is his most peculiar property, whether he received it as a ready-made gift, or worked it out laboriously from a lower condition in tens of thousands of years. But if his present constitution is not in the slightest degree injured by his (assumed) animal origin, neither can his aims and tasks, his endeavours and vocations-in short, his whole future-be any other than, from his entire nature, he must imagine and believe it to be. Or must the cultivated portion of mankind be really so profoundly dismayed by the idea of descending from apes, that in despair at the impossibility of maintaining and improving the civilization, which by no means fell into their lap like ripe fruit, but which was painfully acquired, they would abandon their business and pursuits, their forms of law and government, their arts and sciences, and sink to the level of the Australian bushmen-that they would let go that by which they had raised themselves so far above the apes, and by which they are constantly raising themselves still higher, merely because it was once difficult to raise themselves above these apes even by a hair's breadth? But what man destined by nature for a ruler, would have refused to grasp the crown because his father was a hind? Or what born Raphael would have forsworn palette and pencil, because his parent had been a sign-painter ? Mankind, like each individual, will use and improve its powers because it has them, not because it has obtained them from hither or thither."
We give these transient fireworks their due, but we require more profound arguments whence to derive the final verdict. To the votaries of the doctrine of Descent,
its application to man is a simple deduction from a general law, gained by the method of induction. As Goethe postulated the inter-maxillary bone in man even before he had seen or proved it, so must the doctrine of Descent extend to man all its results and more or less plainly demonstrated laws. The deduction is effected by the accumulated observations of comparative anatomy, evolutionary history, and paleontology, checking and confirming one another. Thus, for all who are not satisfied with belief in miracle and subjection to the hypothesis of a revelation, nothing remains but the doctrine of Descent. To apply it to man is not more hazardous, but, on the contrary, as inherently necessary, as it is for us zoologists to make use of it in judging some polype hitherto unknown, a star-fish or a mouse. This our adversaries deny. Man, they say, has qualities which separate him absolutely from the animal, and, assuming the doctrine of Descent generally, preclude its applicability in this one case. To this assertion, so frequently to be heard, we will, in the first instance, oppose a general remark as to the apprehension of human
It is commonly overlooked that, quite regardless of the validity of the doctrine of Descent or even of its existence, there is a notable inconsistency in the idea of humanity. The philosophy of history has regarded mutability, which is, in fact, capability of progress, as the essence of human nature. But if any sort of inseparable dependence of the mind upon the body be admitted, as is the case with all but an extreme spiritualistic party, the progress of mental power in mankind was inconceivable without some parallel trans
formation of the bodily substratum extending beyond the limits of mere variability. Even on the assumption that the mind forms its own organ, the brain, the specific idea of man would necessarily have consisted in bodily improvement, as contrasted with the supposed rigidity of the animal organism. For, in principle, it is the same whether changes take place perceptibly in arms and legs, or imperceptibly to the eye, in the molecules of the brain. We are, therefore, only retrieving the shortcomings of philosophy when we attribute to the bodily mutability of man the extension which accrues to it from the applicability of the doctrine of Descent to the particular case.
The bodily accordance betwixt man and animal leaves the doctrine of Descent so little to desire, that the apprehension of Mephistopheles lest grovelling humanity should finally be alarmed at his likeness to the Deity, might far rather be applied to his likeness to the animal. The human body, like the body of every animal, points in its evolution to an elaboration from the undifferentiated to the specialized form. The general distribution of the body and the development of the several organs is common to man and all mammals, and in the earlier stages of the embryonic state to all vertebrate animals, and indicates this general kinship. The existence therefore of a discoidal placenta (unless we prefer a special reiterated new creation of this organ of development, in which the Creator adhered to the pattern of the placenta of the lemurs, rodents, insectivora, bats, and apes) reduces us to the alternative that in the natural and to us unknown development of man, chance, or some quite different chain of causes, led in this case, as in the other. to the
discoidal placenta, or that the accordance is based on consanguinity with the discoido-placental mammals. We have already (p. 272) objected to the inference that all mammalian orders are akin, should be drawn with certainty from the superficial accordance of the placenta, and we must therefore justify ourselves now, when we lay a stress on the accordance of the placenta of man and apes. The orders mentioned above all possess a placenta of small extent and discoidal form. In the shape of this disc, and in the number and distribution of the blood-vessels in the umbilical cord by which the foetal respiration and nutrition are carried on, sundry varieties occur. Thus in the family of the Pithecoid apes, the placenta falls into two discs, whereas the umbilical cord agrees with that of man; in the American apes, on the contrary, the placenta is simple and the blood-vessels are different. In the orang and gorilla we know nothing of these organs, but the chimpanzee agrees with man, in that it has a simple discoidal placenta with two conducting (arteriæ umbilicales) and one reconducting vessel (vena umbilicalis).
With a general similarity of the human placenta with that of the discoido-placental mammals, man is specifically nearer to one at least of the so-called Anthropoid apes, than this one is to the other apes. And thus the constitution of the placenta is certainly of great importance in discriminating the systematic position of man. Enormously improbable as is the chance contemplated above, equally probable and solely credible is consanguinity; and with regard to general organization, in any specific comparison of man with the mammalia, the apes must occupy the foreground.