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between successive individuals the only difference is that of race. Now, as we have seen, the fertility among races of the . same species remains constant, and consequently, in the hypothesis of Darwin, as in that of Lamarck, etc., the fertile crossings would in every sense of the word constantly confuse the original and the derived species which was in process of formation. The same
cause having produced the same effects since the commencement of the world, the organic world would present the greatest confusion instead of its well-known order.
Darwin, then, himself and his most enthusiastic adherents must admit that at some given moment these races became suddenly incapable of crossing with their predecessors. Whence then arises the sterility which separates species ? When, and at what moment will the physiological bond be broken, which unites the original species with its modified descendants, even when this modification is carried as far as the ordinary ox and the niata? What will be the determining cause of this great fact which obtains through the whole economy of the organic kingdom?
In his work upon the Variation of Animals and Plants, Darwin replies: “Since species do not owe their mutual sterility to the accumulative action of natural selection, and a great number of considerations show us that they do not owe it to a creative act, we ought to admit that it has been produced incidentally during their gradual formation, and is connected with some unknown modification of their organisation."
We have seen that, in the last editions of the Origin of Species, he refuses to admit that fertility among mongrels is general, taking his stand upon our ignorance on the subject of crossings between wild varieties (races).
Thus, in order to admit the physiological transmutation of race into species, a fact which is contrary to all positive facts, Darwin and his followers reject the secular results of experience and observation, and substitute in their place a possible accident, and the unknown.
The Darwinian theory relies entirely upon the possibility of this transmutation. We see upon what data the hypothesis of this possibility rests. Now, in a truly liberal spirit, I ask every unprejudiced man, however little he may be conversant with science, the question, is it upon such foundations that a general theory in physics or chemistry would be founded ?
V. Moreover, the argument, of which we have just seen an example, may be found in every page of Darwinian writings. Whether a fundamental question, such as we have just been examining, or a minor problem, as the transmutation of the tomtit into the nuthatch, is under discussion, possibility, chance, and personal conviction are invariably adduced as convincing reasons. Is modern science established upon such foundations ?
Darwin and his disciples wish that even our ignorance on the subject of certain phenomena should be considered as in their favour. The question has often been argued on the ground of palæontology, and they have been asked to point out a single instance of those series which ought, according to them, to unite the parent species with its derivatives. They admit their inability; but they reply that the extinct fauna and flora have left very few remains; that we only know a small part of these ancient archives; that the facts which favour their doctrine are doubtless buried under the waves with submerged continents, etc. “This manner of treating the question," Darwin concludes, “diminishes the difficulties considerably, if it does not cause them to disappear entirely."
But, I again ask the question, in what branch of human knowledge, except these obscure subjects, should we regard problems as solved, for the very reason that we possess none of the requisite knowledge for their solution?
I do not intend to reproduce here the entire examination which I have made elsewhere of the transmutation theories in general, or of Darwinism in particular. The above observations will suffice, I hope, to show why I could not accept even the most seductive of these theories. In certain points they agree with certain general facts and give an explanation of a certain number of phenomena. But all without exception attain this result only by the aid of hypotheses which are in flagrant contradiction with other general facts, quite as fundamental as those which they explain. In particular, all these doctrines are based upon a gradual and progressive derivation, upon the confusion of race and species. Consequently they ignore an unquestionable physiological fact; they are entirely in opposition with another fact, which follows from the first, and is conspicuous from every point of view, the isolation, namely, of specific groups from the earliest ages of the world, and the maintenance of organic order through all the revolutions of the globe.
Such are my reasons for refusiug my adherence to Darwin's theories.
VII. The theory of the English naturalist is certainly the most vigorous effort which has been made to trace back the origin of the organic world by processes analogous to those which we have discovered in the genesis of the inorganic world, that is to say, in only having recourse to secondary
He has failed, as we see, like Lamarck. These eminent men will be succeeded by others who will attempt the solution of the same problem. Will they be more fortunate ?
No one is less inclined than I am to place any limit upon the extension of human knowledge. Yet the extension of our scientific knowledge, in the widest sense of the term, is always subordinate to certain conditions. The most attentive examination, even of a human work, will never teach us anything of the processes which have permitted its realisation. The cleverest watchmaker, if he has not followed studies perfectly foreign to his vocation, will know nothing of the origin of iron, of its transformation into steel, of the rolling and tempering of a main spring. The minutest study of that metallic ribbon which he knows so well, will tell him nothing of its origin, nothing of the process of its fabrication,
To know more he must leave his shop and visit the furnaces, the forges, and the rolling mills.
In the works of nature it is the same. With nature as well as with ourselves, the phenomena which produce are very different from those which preserve, and from those displayed in the object produced.
The most complete anatomical and physiological study of an animal or of a full-grown plant will certainly teach us nothing about the metamorphoses of the microscopic cell from which sprang the dog, the elephant, and man himself.
Now hitherto we have only directed our attention to species already formed. We can therefore learn nothing more relative to their mode of production.
But we know that the unknown cause which has given birth to extinct and living species has been manifested at different times and intermittingly upon the surface of the globe. Nothing authorises us to suppose that it is exhausted. Although it appears to bave generally acted at times which correspond to great geological movements, it is not impossible that it may be at work on some point of the earth even at this epoch of relatively profound rest. If this is the case, perhaps some happy chance will throw a little light upon the great mystery of organic origins. But until experience and observation have taught us something, all who wish to remain faithful to true science, will accept the existence and succession of species as a primordial fact. He will apply to all what Darwin applies to his single prototype; and, in order to explain what is still inexplicable, he will not sacrifice to hypotheses, however ingenious they may be, the exact and positive knowledge which has been won by nearly two centuries of work.
ORIGIN OF THE HUMAN SPECIES. — DIFFERENT HYPOTHESES.
I. THE preceding chapter might enable me to dispense with a discussion of the applications which have been made of Darwinism to the history of man. Nevertheless, apart from the curious points in the subject itself, some discussion of it will be necessary, for it will not be devoid of instruction.
Lamarck endeavoured to show how, by means of his theory of habit, it was possible to conceive the direct transmutation of the chimpanzee into man.
The Darwinists also agree in connecting man with the apes. Nevertheless none of them point out any of the species at present existing as our immediate ancestor; on this point they differ from their illustrious predecessor. It might be supposed that Vogt had determined this point if we take literally some passages of his Leçons sur l'homme.
But the Genevese savant has clearly expressed his theory in his Mémoire sur les Microcéphales. He carries back the point of departure common to the two types to an anterior ancestor. Darwin, Wallace, Filippi, Lubbock, Haeckel, etc., connect man still more closely with the apes. The latter states his conclusions in the following terms: "The human race is a branch of the catarrhine
he was developed in the old world, and sprang from apes of this group, which have long been extinct.”
II. Vogt disagrees with his scientific colleagues in an important point. He admits that different simian stocks may have given rise to different human groups. The populations of the old and the new world would thus be descendants of the different forms wbich are peculiar to the two continents. On this hypothesis, Australia and Polynesian