never be created by an individual. True, individuals have invented Esperanto and other artificial languages. Unless, however, language had already existed, these inventions would have been impossible. Moreover, none of these languages has been able to maintain itself, and most of them owe their existence solely to elements borrowed from natural languages. How, again, could a religion have been created by an individual? There have, indeed, been religions whose founders were individual men: for example, Christianity, Buddhism, and Islamism. But all these religions rest on earlier foundations; they are elaborations of religious motives arising within particular folk communities. Thus, then, in the analysis of the higher mental processes, folk psychology is an indispensable supplement to the psychology of individual consciousness. Indeed, in the case of some questions the latter already finds itself obliged to fall back on the principles of folk psychology. Nevertheless, it must not be forgotten that just as there can be no folk community apart from individuals who enter into reciprocal relations within it, so also does folk psychology, in turn, presuppose individual psychology, or, as it is usually called, general psychology. The former, however, is an important supplement to the latter, providing principles for the interpretation of the more complicated processes of individual consciousness. It is true that the attempt has frequently been made to investigate the complex functions of thought on the basis of mere introspection. These attempts, however, have always been unsuccessful. Individual consciousness is wholly incapable of giving us a history of the development of human thought, for it is conditioned by an earlier history concerning which it cannot of itself give us any knowledge. For this reason we must also reject the notion that child psychology can solve these ultimate problems of psychogenesis. Among cultural peoples, the child is surrounded by influences inseparable from the processes that arise spontaneously within its own consciousness. Folk psychology, however, in its investigation of the various stages of mental development still exhibited by mankind, leads us along the path of a true psychogenesis. It reveals well-defined primitive conditions, with transitions leading through an almost continuous series of intermediate steps to the more developed and higher civilizations. Thus, folk psychology is, in an important sense of the word, _genetic psychology_.