| Vygotsky, Leo (Lev Semionovich, 1896-1934), The most outstanding Soviet psychologist, and founder of the most influential school of Soviet psychology, Vygotsky was born in Orsha (Belorussia), and began his work in psychology after leaving Moscow University (faculty of letters) in 1919. As a young man he wrote the subsequently well-known pieces that were included in the Psychology of Art (1965; Eng. trans. 1971). Psychological analysis of the personality of Hamlet, as well as studies in the psychology of fables, were central to the work of this outstanding young scholar. After a few years in Gomel (Belorussia), where he taught psychology and wrote Pedagogical Psychology (1926; in Russian), he moved to Moscow, where his most important work began. He soon became a leading figure of the Institute there, and the central figure in a group of young scholars (including A. N. Leontiev and A. R. *Luria) who became his first co-workers and followers.
At the time of his early studies, psychology was in a state of crisis. It was split into two independent sciences. The first was the explanatory or physiological psychology of *Wundt and *Ebbinghaus, who tried to explain complex psychological phenomena by reducing them to elementary physiological components. They refused to deal scientifically with the highest, specifically human forms of conscious behaviour — motives, abstract thinking, active memorizing, voluntary actions, etc. The second school attempted a descriptive psychology which did consider the highest forms of conscious experiences, treating them as spiritual forms of mental life, and supposing that these phenomena may be described in *phenomenological terms but not explained scientifically.
Vygotsky assumed that the basic goal of scientific psychology was to overcome this division, and to try to explain scientifically not only the elementary but also the highest forms of psychological processes. This — he thought — could be done by reducing the complex psychological phenomena not to physiological ‘elements’, but rather to more complex psychological ‘units’, which would preserve all the properties of the complex forms of conscious behaviour and which could serve as its models, making the more complicated forms of mental life accessible for scientific analysis.
Supposing the highest forms of mental life and conscious behaviour to be not of a spiritual nature but a product of social development, Vygotsky saw tool-using and sign-using (‘significative’) behaviour as essential for all higher forms of psychological processes. He also considered forms of sign-using behaviour, its rules, and the stages of its development. Studies in sign-using, as a model of complex active *memory, were his first attempt to approach experimentally the most complicated psychological processes. (The results of these studies were published by A. N. Leontiev.)
His work on simple ‘units’ of tool- and sign-using behaviour led Vygotsky to investigate the role that language (the most universal system of signs) plays in human behaviour, and to a careful analysis of its development during the life of the individual. The main purpose was to describe the semantic structure of words. His famous experiments with artificial words (the Vygotsky-Sakharov technique) were published later by Hanfman and Kasanin and became known as the Vygotsky-Hanfman-Kasanin tests.
These investigations led Vygotsky to one of his main discoveries — that the meaning of words undergoes a complex development, and that words starting as emotional soon become concrete designations of objects later to acquire abstract meaning. (See Language: learning word meanings.) This conclusion was followed by the statement that the whole of mental development can be understood as a profound change of psychological systems which mediate the basic forms of activities; and that with each new stage the leading function changes. So, Vygotsky supposed, the child is thinking by memorizing, whereas the adult is memorizing by thinking. This systemic approach to complex psychological functions was one of the most important steps in contemporary psychology.
The idea that the higher psychological processes have a social origin brought Vygotsky to a new approach in the evaluation of the child’s mental development, and to the assumption that not only the actual ‘mental age' of the child has to be measured, but also its potential capacities — what he called ‘the zone of potential development’. This can be done by comparing how the child solves certain problems by itself with a second indicator: how it can solve similar tasks with the help of the teacher — representing here the ability to acquire social prompting. The principles proposed by Vygotsky were of the highest importance for practical educational and clinical psychology.
During his short life in science (he died at the age of 37 from tuberculosis, and worked actively in experimental psychology only for about ten years), Vygotsky was active in many fields of scientific psychology: general psychological problems, child psychology, the problems of retarded and deaf children, the psychological analysis of local brain injuries, and a series of related fields. Although his career was very brief, his influence on Soviet and world psychology has become more and more significant with the passing years. In addition to the two works mentioned, his most important books are Thought and Language (1937; Eng. trans. 1962); Selected Psychological Studies (1956; in Russian); and Development of the Higher Mental Processes (1960; in Russian).