Lev S. Vygotsky (1896?1934) studied at Moscow University. He began his systematic work in psychology at the age of 28, and within a few years formulated his theory of the development of specifically human higher mental functions. He died of tuberculosis in 1934. Thought and Language was published posthumously that same year.

Alex Kozulin began his investigation of Vygotsky's theory at the Moscow Institute of Psychology and continued it in Boston and then Jerusalem. He is the author of Psychology in Utopia: Toward a Social History of Soviet Psychology (MIT Press, 1984), Vygotsky's Psychology: A Biography of Ideas, and a coeditor of Vygotsky's Educational Theory in Cultural Context.