"We cannot, I repeat, explain perfectly the how and the wherefore; but what we know is, that the fact exists, and we shall find a general explanation in all states of existence--in all conditions of people.
"It is not, then, surprising that man presents, in the different groups, the differences herein depicted; man who trod the earth long before the turkey and the rabbit; man, who for centuries has existed upon the surface of the globe, submitting to the most diverse and opposite conditions of existence, multiplying again the causes of those modifications by his manners and habits, by his ways of living, by more or less care in his own preservation; man, finding himself in more marked and varied conditions than those sustained by the animals we have quoted. If anything surprises us, it is that the distinctions are not more considerable.
"In turn, ask the polygenists--as those _savans_ are called who believe in the multiplicity of the human species--how it is that when the white man locates in any country, from the antipodes, if you will, or from America or Polynesia--that if he unites with the natives, who differ the most completely from him, these unions are fruitful, and that, above all, there remains traces of this alliance in producing a mongrel race?
"If you press the question more closely, you will find them denying the truth of species; by so doing, placing themselves in contradiction with all naturalists, botanists, or zoologists, without exception; consequently, with all the eminent minds who have followed in the wake of Buffon, Tournefort, Jussieu, Cuvier, and Geoffrey St. Hilaire, who made the animal and vegetable kingdoms their study, without discussion, or dreaming of its connection with man. In agitating these doctrines, polygenists place themselves in opposition to the most firmly established science. You will hear them declare that man, above all, is an exception; that he is guided by laws peculiar to himself; and that arguments deduced from the study of animals and plants, are not applicable to him. Then reply that, in the name of all the natural sciences, they are certainly in error, and that it is an impossibility that a living and organized being can escape the laws of organization and of life, having a body fortified against the laws that govern inorganic matter; that man, to be living and organized, obeys, under this title, all general laws, and those of intersection like all the others. The conclusion that we have attained is, then, legitimate, and the nature of the arguments employed to combat them, is a proof the more in its favor.