The article deals with the dramatic opposition of psychologism and antipsychologism. Due to the evident success of classical branches of mathematical logic in the XX century psychologism was completely eliminated as a methodological basis for logical and mathematical knowledge for its conceptual insolvency, as an outdated and technically inefficient trend towards anthropologization of scientific theories. However, non-classical logic’s and recent neuroscience’s (especially socio-cultural neuroscience) vigorous development has again brought psychologism to the proscenium of science and logico-mathematical thought. We are making attempt to analyze the reasons for the revival of psychologism and vistas to preserve its position as one of the modern cognitive science leading conceptions. We ponder over the ontogenetic foundations of the socio-cultural activity of man and the reverse effect of this activity on the formation, as well as the dynamics of activity of neural structures and their architectonics. They are the important factors related to the deep foundations of the psychological organization and cognitive potential of personality, as well as of epistemological communities due to active interaction of elements within the integral system “brain-society-culture”. A classification of approaches to the interpretation of psychologism is proposed; the boundaries of the deanthropologization of scientific knowledge are under scrutiny. We show that psychologism has solid ontogenetic background and, consequently, an absolute deanthropologization of scientific knowledge, actually presupposed by antipsychologism, in the general case turns out to be too categorical and unattainable. The manifestation of the Baldwin effect in the evolution of living and social systems is discussed, when a change in the behavior of a social system and/or group can lead to a change in the natural selection factors and, consequently, to new directions of its development. We judge that in accordance with the Baldwin effect, each component of the chain “genes - structures - functions – experience” is in a state of at least bi-directional interaction: the activity and composition of the genes that set the psychological landscape depend on the nature of the environment (culture included). The environment changes as result of the activity and psychological attitudes of the increasing mass of carriers of the activity of a given set of genes.