Problems in the Integrated Study of Individual Differences

The properties of all the stages of evolution of matter, from the chemical to the sociohistorical, are part of man as well. In each of these properties, in addition to what is common and typical for groups of people, there is something that is unique to the individual and irreproducible. One characteristic noted in theoretical conceptions of individual differences is that they tend to study properties relating to different stages in the development of matter in isolation from one another. In most studies of differential psychophysiology, the biochemical and endocrine properties of the organism and the bioelectric properties of the nervous system are examined as if they had nothing to do with individual characteristics in the formation of classical Pavlovian conditioned reflexes. The psychological properties of the personality are examined in the Vygotsky and Leont'ev school independently of their relationship to somatic, neurophysiological, and psychodynamic properties (the properties of temperament).