This volume of the monograph includes three initial thematic sections: the first, devoted to the problem of the reality of the unconscious as a psychological phenomenon; the second, covering the evolution of ideas about the unconscious psychic in modern psychoanalytic literature (60s - 70s), and the third, which addresses the neurophysiological foundations of the unconscious. The content of these sections is preceded by "Introduction," which briefly characterizes the history of the development of unconscious concepts, the features of the modern formulation of this problem and the provisions on the basis of which the latter is currently being developed in the psychological school of D. N. Uznadze. It seems to us that such an arrangement of the material with its separation into a separate volume contributes to the logical ordering of the presentation and facilitates its understanding.