That is to say, Darwin's _Origin of Species_ does not explain the Origin of Species; and as to the laws which govern Evolution we can be sure only that they are not those which he assigned. In like manner, Sir Oliver Lodge pronounces:[237] Take the origin of species by the persistence of favourable variations; how is the appearance of these same favourable variations accounted for? Except by artificial selection not at all. Given their appearance, their development by struggle and inheritance and survival can be explained; but that they arose spontaneously, by random changes without purpose, is an assertion which cannot be made. We are thus in a position to form our own judgment as to the claim made on behalf of Mr. Darwin, with which we started this chapter--namely, that he has eliminated all mystery from the organic world by the discovery of natural mechanical laws by which all its operations are governed. It is, indeed, difficult to understand how Darwinists themselves can suppose their system to make any such claim, for, as M. Paul Vignon truly observes,[238] "La science darwinnienne s'imaginait avoir triomphé du Sphinx, alors qu'elle avait simplement décomposé le problème dans une monnaie d'énigmes moins rébarbatives en apparence." As has been said, it is far more on account of the vast consequences professedly based upon it, as a sure foundation stone, than for its own sake, that it has seemed advisable to devote so much attention to the study of Darwinism, quite apart from which the whole question of organic Evolution still demands consideration. It seems far more just to conclude with M. Fabre:[239] Let us acknowledge that in truth we know nothing about anything, so far as ultimate truths are concerned. Scientifically considered nature is a riddle to which human curiosity can find no answer. Hypothesis follows hypothesis, the ruins of theories are piled one on another, but truth ever escapes us. To learn how to remain in ignorance may well be the final lesson of wisdom.[240] XVI THE FACTS OF EVOLUTION Leaving the field of speculation and "ætiology," we have now to enquire, not to what causes organic Evolution may be attributable, but how far it can be shewn to have actually occurred. This can be learnt only from the history of life upon earth as disclosed by the evidence of palæontology, or the geological record, and we are thus brought to the investigation of that evidence, by which alone, as Professor Huxley agrees, can the truth about Evolution be scientifically or satisfactorily established. In his address recently mentioned on occasion of the twenty-first birthday of the _Origin of Species_, having spoken of various advances of our knowledge, as in comparative anatomy and embryology, which had helped to win acceptance for transformist doctrines, he thus continued: