These questions have been answered alternately in the different senses which they admit of. Unfortunately these solutions have too often been influenced by considerations entirely foreign to science. It has been thought necessary to adopt either the one or the other in the name of dogma or philosophy, and this question has been confounded with that of monogenism and polygenism, without seeing that upon this particular point the two doctrines must lead anyone who remains faithful to the data of science to the same result. Science has already been shown to be our only possible guide; let us examine her teaching on this subject.
II. The doctrine which admits the multiplicity of the geographical origins of man, has been more frequently asserted, than sustained by more or less serious arguments. Agassiz is the only naturalist who has developed and defined it, by supporting it with general data. We must, therefore, first examine these data. A very short account will explain the reasons why I must, with regret, oppose one of the men whose learning and character I have always held in the highest estimation.
There are singular points of resemblance, and no less striking contrasts between Agassiz and the most extravagant disciples of Darwin. The illustrious author of the Essay on Classification is as exclusive a morphologist as the latter; neither in his opinion nor in theirs, does the idea of filiation form any connection with that of species; he declares, as they do, that the questions of crossing, of constant or limited fertility, have no real interest. We are justified in attributing these opinions, so strange in such an eminent zoologist as Agassiz, to the nature of his early works. It is well known that he commenced his career with his celebrated researches upon fossil fishes. We have already remarked upon the influence which is almost inevitably exercised by fossils, where form alone has to be considered, where nothing calls attention to the genealogical connection of beings, and where we meet with neither parents nor offspring.
But while Darwinists admit the perpetual instability of specific forms and their transmutation, the illustrious professor of Cambridge believes in their absolute immutability. Upon this fundamental point he is in exact opposition to Darwin. In 1840, whilst proclaiming the unity of the human species, he admits that the diversity which it presents is the result of original physical differences. This is really nothing more than a mitigated polygenism; and, like every polygenistic doctrine, compels its author to place man in contradiction to general laws. In 1845, Agassiz himself accepted this consequence in a memoir upon the geographical distribution of animals and man. He attributed the diversities of both to the same causes. “But,” he adds, “whilst in every zoological province animals are of different species, man, in spite of the diversity of his races, always forms one and the same species.” The following year he declared his belief in “an indefinite number of primordial races of men created separately.”
Agassiz has collected and developed all his theories in a memoir inserted at the beginning of the great polygenistic work entitled Types of Mankind. It is clear that Nott and Gliddon, the authors of this work, were perfectly aware of the real meaning of a doctrine which proclaims the specific unity of man, while at the same time admitting that the human races have been created separately with all their distinctive characters. We, also, must not be deceived, but recognise Agassiz as a true polygenist.
I shall, therefore, be obliged to make all those objections to the theory of the eminent naturalist which have already been stated. Moreover, the singular association which he has endeavoured to establish between the unity of species and the original characterisation of races, has led him into contradictions and consequences which are peculiar to him, and which it would scarcely be possible to pass by in silence.
Agassiz, like the greater number of polygenists, gives no intimation of what he means by the word race. Yet he makes use of it incessantly and declares, for example, that he is ready to show that “the differences existing between human races are of the same nature as those which separate families, genera, and species of apes or other animals....” “The chimpanzee and the gorilla,” he adds, “do not differ from each other more than Mandingoes from the Negroes of Guinea; there is less difference between either of them and the orang, than there is between the Malay or the White and the Negro.”
Must not the logical consequence of such positive language be, that man forms a zoological family comprising several genera and many species, precisely similar to the family of anthropoid apes? But no; Agassiz devotes a new paragraph to declaring that this opinion, which he has expressed so clearly, agrees entirely with the theory of unity, and in no way brings human fraternity into question. In one of his first memoirs upon questions of this nature, he declared that man is an exceptional being, and we shall see how far he pushes this unavoidable consequence of his theories.
In a letter addressed to the same authors, and printed in the Indigenous Races of the Earth, Agassiz returns to the same subject. He here insists upon considerations which, in his first work, he had merely alluded to, and which we are truly astonished to receive from his pen. In order to show that the same local causes have acted upon man and animals, he draws attention to the resemblance of colour, which, according to him, exists between the complexion of the Malay and the colour of the hair of the Orang; from the same point of view he compares the Negrittoes and Telingas with the gibbons.
If it were possible to consider seriously this comparison between the skin of a human group, and the colour of the hair of an animal, we should have no lack of arguments to bring against the author. I shall only remind my readers that black gibbons are found in Sumatra, which is one of those islands where men are considered by Agassiz to resemble the orang in colour.