Buffon, Georges Louis Leclerc, Comte de (1707–88)
Both as a scientist and as a writer, Buffon was one of the most highly esteemed figures of the European Enlightenment. In depicting the perpetual flux of the dynamic forces of Nature, he portrayed the varieties of animal and vegetable species as subject to continual change, in contrast with Linnaeus, whose system of classification based on physical descriptions alone appeared timeless. But Buffon’s definition of a species in terms of procreative power excluded the evolutionary hypothesis that any species could become transformed into another. Hybrids, as imperfect copies of their prototypes, were in his scheme ultimately destined to become sterile rather than to generate fresh species. By virtue of the same definition, he judged that the different races of mankind formed family members of a single species, since the mating of humans of all varieties was equally fertile.