This paper briefly summarizes Durkheim’s theory of the dual nature of man suggested earlier in his Elementary Forms of Religious Life. It is characteristic of human beings that two opposite principles confront each other within them: soul and body, concept and sensation, moral activity and sensory appetites. Although this inherent inconsistency of man has been long recognized by philosophical thought, no doctrine explanation to it has been provided to date. While empiricist monism has proved to be unable to explain how concepts emerge from sensations and disinterestedness develops from self-interest, absolute idealism, on the contrary, cannot deduce sensations from concepts. Although theories suggested by Plato and Kant do not bypass the problem of dualism, they only rephrase it and make no progress in solving it. According to Durkheim, dualism of human nature stems from the fact that all religions are founded on dividing all things into the sacred and the profane. This division, in turn, is explained by coexistence of collective and individual origins in the human being. Sacred things arise out of the collective origin that enables individual consciousnesses to fuse into communion. Collective origin does not act with constant strength, but intensifies during the periods of effervescence, when it subdues the individual origin. Since the importance of the social aspect of man increases over time, there is no reason to believe that complete consent between individual and society is possible that would endow man with internal harmony.