Many supporters of D.N. Uznadze's theory of set describe the set as a mental phenomenon. At the same time it is understood that the set is of unconscious nature. From this point of view therefore the set is the unconscious psychological. In the majority of his scientific works D.N. Uznadze defined the set as an infra-mental sphere of individual activity. It follows from his principal scientific paradigm: unity and integrity of the external and internal, of the subjective and objective, of the physiological and psychological. He was able to overcome the Cartesian dualism and developed a monistic approach to the psychological study of personality. Although in his last work D.N. Uznadze put the sign of equality between the set and psyche, his initial position appears more correct. Only this position makes it possible to overcome the "immediateness postulate" of the traditional psychology.