Natural selection has artificial selection for its ideal godfather, but what has the latter produced? Not only no species, but not even a permanent race definitively fixed and acquired. All the races made by the hand of man die if they are left to themselves, unsupported by an artificial selection constantly at work. It is a fact which M. Faivre supports with superabundant demonstration, taken from both the vegetable and animal kingdoms. The collection of those facts is truly irresistible. What! the continued transformation of species is given to us as a law, and yet we cannot find a solitary transformed species! The transformation of races, which must not be confounded with that of species, is itself conditional and relative, is soon effaced if nothing disturbs the return of the race to the pure type of the species, and yet we are told of the power of natural selection and of the battle of life which consecrates this power! This selection, this vital concurrence, this action of means, have been all employed to modify the proximate species, as the horse and the ass; domestication offered here all its resources; the hand of man could choose, ally, and cross the types at will.
"Assuredly," says M. Flourens, "if ever a complete reunion of all the conditions most favorable to the transformation of one species into another could be imagined, this reunion is found in the species of the ass and horse. And, nevertheless, has there been a transformation? … Are not those species as distinct to-day as they have always been? Among all the almost innumerable races which have been produced by them, is there one which passed from the species of the horse to that of the ass, or, reciprocally, from the species of the ass to that of the horse?" Why, say we with M. Faivre, pay no attention to such simple facts, and take so much trouble to seek outside of evidence explanations which do not agree with the reality?
The theories of Darwin have become the chief support of those who attribute to man a monkey origin. "I prefer to be a perfect monkey to a degenerate Adam," says one of the partisans of these theories. But why can they not perfect an ass so as to make a horse of it? There is not between these two latter species the profound anatomical difference which exists between the monkey and man—a difference so well established by Gratiolet, a great mind and a true savant. On what, then, can be founded the theory of our descent from the monkey species, since the slightest change resists all fusion, all transition from one neighboring species to another?
The book of the Variabilité des Espèces is the answer of facts to the spirit of system. Calm and severe, rigorous and cold, this book admits only the testimony of nature. It will instruct and convince those who doubt on those questions. The author terminates by those conclusions which we willingly reproduce because they allow us to divine something else besides the indifferent study of facts; they are perhaps the only lines of the work where the sentiment of the moral dignity of man is apparent. "This hypothesis (namely, of the mutability of species) is not authorized," says M. Faivre, "either by its principle, which is a mere conjecture; or by its deductions, which the reality does not confirm; or by its direct demonstrations, which are hardly probabilities; or by its too extreme consequences, which science as well as human dignity forbid us to accept—the theory of spontaneous generation, the intimate and degrading relationship between man and the brute."
Notwithstanding the ability—we may almost say the genius—which illustrious savants have employed in defending the doctrine, reason and experience have not weakened the reserved and just judgment which Cuvier has passed upon it, and which will serve as the conclusion to this essay: "Among the different systems on the origin of organized beings, there is none less probable than that which causes the different kinds of them to spring up, successively, by developments or gradual metamorphosis."
One word more before quitting the subject. All these great forms of scientific error spring up in our old Europe, where they find at the same time numerous and passionate adherents, and firm and eloquent opponents. The attack and the struggle are kept up incessantly in the press, in our books, in our learned bodies, in our teaching faculties. If we examine the general character of these conflicts, we find in them truth almost intimidated, certainly less bold and less respected than error. Truth is self-conscious, and that is sufficient to prevent it from becoming weak or yielding to fatigue and discouragement; but it has not popular favor; it is tolerated, but hardly ever greatly encouraged. If we quit this tormented Europe, which is drawn only toward new errors, and cast our eyes toward those great United States of America, that fertile land appears to us as favorable to truth as to liberty. Let us listen an instant to that illustrious savant who has no superior in the domain of natural science, M. Agassiz; let us follow his teaching in the University of Cambridge. What elevation and what sincerity! How all those systems which seduce so many minds in these cisatlantic regions are brought to their true proportions—judged in their profound disregard of the laws of nature! Let us take, for instance, the influence of exterior conditions and of physical agents on animals—the basis of the system of Lamarck, and one of the principal conditions of the mutability of species in Darwinism. M. Agassiz, on this point, uses again the firm language which from the days of Cuvier natural science has not spoken in France:
"In so far as the diversity of animals and plants which live in the same physical circumstances proves the independence as to the origin of organized beings, from the medium in which they reside, so far does this independence become evident anew when we consider that identical types are found everywhere on the earth in the most varied conditions. Let all those different influences be united—all the conditions of existence, under the common apellation of cosmic influences, of physical causes, or of climates—and we shall always find in this regard extreme differences on the surface of the globe, and nevertheless we shall see living normally together under their action the most similar or even identical types. … Does not all this prove that organized beings manifest the most surprising independence of the physical forces in the midst of which they live, an independence so complete that it is impossible to attribute it to any other cause than to a supreme power governing, at the same time, physical forces and the existence of animals and plants, maintaining between both a harmonical relation by a reciprocal adaptation in which we can find neither cause nor effect? … It would be necessary to write a volume on the independence of organized beings of physical agents. Almost everything which is generally attributed to the influence of the latter must be considered as a simple correlation between them and the animal kingdom resulting from the general plan of creation." [Footnote 111]
[Footnote 111: Revue des Cours scientifique, Mai 2, 1868.]