During all these disputes Harvey’s formula had, however, won such a stability and approbation that Büchner himself under its pressure formulated his position in the following cautious words: “Even if recent scientific researches have more and more limited the ground for spontaneous generation, it is nevertheless not improbable _that it even now takes place among the lowest and least developed organisms_.” It may willingly be conceded that this assertion was in its time by no means without foundation. But scarcely could Büchner or anybody else at that moment imagine how soon the hour of decision would strike. Shortly after 1860 the many centuries old question was finally settled almost simultaneously by Hoffman and Pasteur. Through the latter’s masterly investigations it was fully demonstrated that parentless generation does not exist in the micro-organic world either. Before Pasteur’s simple and clear evidence, opposition was silenced even so far that the question has almost entirely ceased to occupy our attention. _Omne vivum ex vivo_ appears now to be an unchallenged truth. Life implies life. But although science thus rejected _generatio spontanea_, the materialists nevertheless occupy a very strong position on the selfsame foundation as formerly, and continue the defense apparently not without some success. In spite of Büchner’s real, or perhaps partly pretended, confidence, he seems to have had a presentiment of how weak the support of _generatio spontanea_ was, and we find him therefore suddenly reasoning as if its cause were already lost. Thus he makes the entirely sound remark that even if at the present time all animals and plants must have parents, yet nothing whatever is thereby demonstrated in regard to the very first appearance of life in the universe. “If all organic beings have parents, how, then, did the first parents come into existence?” he asks. “When all outer conditions were favorable, might they not have appeared spontaneously, accidentally or necessarily? Or must the first organisms have been created through the intervention of some higher power?” Büchner concedes that this question is extremely complicated, and at first glance may appear unsolvable without the assumption of some such higher being who of his own will created the first organisms as it pleased him and endowed them with the faculty of propagation. “Orthodox scientists point with satisfaction also to this state of affairs,” says Büchner, “and they remind us at the same time of the artful and complicated structure of the world, and warmed by their conviction they see therein the wise arrangements of a higher, personal creator, who built the world according to his personal intentions.”