If all the preceding conjectures be refused by those opposed to us; if it be pretended that Nature acts by a certain quantum of immutable and general laws; if it be believed that men, quadrupeds, fish, insects, plants, are from all eternity, and will remain eternally, what they now are: if I say it be contended, that from all eternity the stars have shone, in the immense regions of space, have illuminated the firmament; if it be insisted, we must no more demand why man is such as he appears, then ask why Nature is such as we behold her, or why the world exists? We are no longer opposed to such arguments. Whatever may be the system adopted, it will perhaps reply equally well to the difficulties with which our opponents endeavour to embarrass the way: examined closely, it will be perceived they make nothing against those truths, which we have gathered from experience. It is not given to man to know every thing--it is not given him to know his origin--it is not given him to penetrate into the essence of things, nor to recur to first principles--but it is given him, to have reason, to have honesty, to ingenuously allow he is ignorant of that which he cannot know, and not to substitute unintelligible words, absurd suppositions, for his uncertainty. Thus, we say to those, who to solve difficulties far above their reach, pretend that the human species descended from a first man and a first woman, created diversely according to different creeds;--that we have some ideas of Nature, but that we have none of creation;--that the human mind is incapable of comprehending the period when all was nothing;--that to use words we cannot understand, is only in other terms to acknowledge our ignorance of the powers of Nature;--that we are unable to fathom the means by which she has been capacitated to produce the phenomena we behold.