linguistics, and ethnology, making feature-by-feature comparisons of their subject matters, were beginning to suspect that similarities between animals, languages, and folkways were the result of processes or laws unknown to them then. For them, the publication of Charles Darwin's On the Origin of Species was the epiphany of everything they had begun to suspect. Darwin himself arrived at his conclusions through comparison of species he had seen in agronomy and in the wild. Darwin and Wallace unveiled evolution in the late 1850s. There was an immediate rush to bring it into the social sciences. Paul Broca in Paris was in the process of breaking away from the Société de biologie to form the first of the explicitly anthropological societies, the Société d'Anthropologie de Paris, meeting for the first time in Paris in 1859. When he read Darwin, he became an immediate convert to Transformisme, as the French called evolutionism. His definition now became "the study of the human group, considered as a whole, in its details, and in relation to the rest of nature". Broca, being what today would be called a neurosurgeon, had taken an interest in the pathology of speech. He wanted to localize the difference between man and the other animals, which appeared to reside in speech. He discovered the speech center of the human brain, today called Broca's area after him. His interest was mainly in Biological anthropology, but a German philosopher specializing in psychology, Theodor Waitz, took up the theme of general and social anthropology in his six-volume work, entitled Die Anthropologie der Naturvölker, 1859–1864. The title was soon translated as "The Anthropology of Primitive Peoples". The last two volumes were published posthumously. Waitz defined anthropology as "the science of the nature of man". Following Broca's lead, Waitz points out that anthropology is a new field, which would gather material from other fields, but would differ from them in the use of comparative anatomy, physiology, and psychology to differentiate man from "the animals nearest to him". He stresses that the data of comparison must be empirical, gathered by experimentation. The history of civilization, as well as ethnology, are to be brought into the comparison. It is to be presumed fundamentally that the species, man, is a unity, and that "the same laws of thought are applicable to all men". Waitz was influential among British ethnologists. In 1863, the explorer Richard Francis Burton and the speech