ABSTRACT
Ever since Vygotsky’s work (1934/1962) was published in Europe and the United States, a substantial number of child language researchers have become interested in his theory regarding the social origins and functional significance of private speech. Vygotsky’s theory of private speech involves three major hypotheses. First, he argued that private speech becomes an important tool for self-regulation as children use language to plan, guide, and monitor their own activity. Second, Vygotsky stated that private speech, in its earliest forms, cannot be clearly differentiated from social speech. According to his theory, the differentiation between social and private speech, as two distinct functional uses of language—communicative and regulatory—occurs gradually in development. Finally, Vygotsky hypothesized that private speech constitutes the overt and observable precursor of covert inner speech or verbal thinking (Wertsch, 1979b, 1980; Wertsch & Stone, 1985).
