The richness of Mead's fundamental themes is so great that a thorough and systematic criticism of his entire range of thought would clearly transcend the limits of our present study. We restrict ourselves necessarily to a consideration of a few major doctrines and focus our discussion upon five central themes which characterize Mead's position: the self, other selves, the act, temporality, and sociality. It might be well to indicate at the outset why these particular problems have been selected from the welter of issues in Mead's work. First of all, it should be clear that any criticism of Mead's general position cannot avoid dealing with the topics we have selected; they are key issues. A second consideration is that the five topics selected are either discussed or implied in all of Mead's work: it is not possible to understand his theories of gesture, communication, language, consciousness, etc., without taking into consideration problems of the self and other selves, the act and its stages, questions of the temporal span of the act and its relation to the present, and, finally, the root issue of the ground of all these structures, sociality. A third factor in our selection of these themes is that they represent problems crucial to the basis and structure of the social sciences to the extent that the latter are fundamentally concerned with the nature of societal reality. In whatever form the themes are articulated, a true understanding of the foundations of the social sciences must involve such problems as the nature of the self, the group, and the situation incorporating both. For all these reasons, Mead's insights not only are of value in themselves, but tend to direct our attention toward the foundational problems of the social sciences.