The study is dedicated to the 95th anniversary of the birth of a prominent Ukrainian scholar, Academician V. Romenets (1926–1998) – the founder of cultural and historical psychology, the author of the theory of deed. The purpose of the study is to analyze ways of explaining the nature of the mental that exist in cultural and historical psychology, to characterize the work of the scholar and deepen the understanding of the subject of this discipline, and to analyze the theory of deed and take the next steps. The first part of the study characterizes the history and current state of cultural and historical psychology, the leading theories in this area, the problems that are not solved. It is stated that the authors of works in this field are just beginning to look in the direction, where the prominent Ukrainian scholar has already paved the way with Herculean efforts and ideas of great significance content. The article substantiates the proposition that the theory of deed of V. Romenets fills cultural-historical psychology with the real content and brings it to a fundamentally new level of development. The second part of the study presents the positions of the concept that sets the guidelines for analyzing the work of V. Romenets, periodization of creativity; the theory of deed is characterized as an explanation of the nature and essence of objectification of mental in action as a cornerstone of historical human existence in culture. According to V. Romenets, the image of a person in the history of culture appears as evidence of the psychology of the era, on this basis, the historical levels of formation of psychological knowledge are distinguished. The components of the theory of deed is given to the words of the scholar: the theory of creativity, the history of world psychology, historical psychology, the life path of a person, philosophy of the transitory, the theory of the sources of human life, a person as an inspiring personality, canonical psychology. The definitions of the components of the main triad in V. Romenets’ thinking are given: person – deed – world. It is noted that due to the work of the scientist, psychology is filled with proper humanistic content and highlights the cultural and historical mission of this science, which is to remind people of the responsibility for what has been done and has not been done, for what has been done and has been lost. It is claimed that the system of knowledge created by the scholar has no analogs in world psychology. The third part of the study analyzes Romenets’ solution to psychology’s main problem, represented by the relationship “subjective – objective”. In this regard, the place of the scholar’s creativity in Ukrainian and world science is determined. It is shown that the theory of deed is constructed by thinking, which is implemented as a deed, the theory of deed is a historical-logical-psychological product, its completion is the logical conclusion of the history of psychology. It is shown that the creativity of V. Romenets is in line with the leading trend in the history of epistemology, which runs from dualism to increasingly meaningful monism. A provision on the principle of involvement is introduced, which fixes the fact of a person’s direct presence in the cognitive process and is further deepened by the idea of the identity of thinking and being. It is shown that the principle of involvement essentially characterizes the creativity of V. Romenets and opens the possibility to see that psychological cognition is carried out by a particular scholar and that the individual in this process lies in the realm of natural as historical-logical-psychological. That which in epistemology acts as anthropocentrism, in psychology arises as the basis of the anthropological approach, the subject of which is the mental of a person as a directly present way of being inherent in it in the being of the world. The positions of the anthropological approach are formulated, it is noted that the approach is formed in the process of analyzing the creativity of V. Romenets and serves to study human life in its specific psychological dimension.