Vygotsky, Lev Semyonovich
VYGOTSKY, LEV SEMYONOVICH
(b. Orsha, Russia, 5 November 1896, d. Moscow, Soviet Union, 11 June 1934), psychology, education, psycholinguistics, psychoneurology.
Vygotsky was virtually unknown in the Western world until the first translations of his writings appeared in English (e.g., Vygotsky, 1961, 1962, 1963). He then quickly gained recognition as an original thinker whose views were important for psychology and education. His so-called cultural-historical theory was influential in the creation of the new field of cultural psychology. His views on mental testing led to the new field of dynamic assessment, and his views on the relationship between education and mental development were implemented in many instructional programs and theories. His ideas about the development and function of inner speech found their way into psycholinguistics. Finally, his criticism of existing theories about the localization of mental functions in the brain was used to create the new discipline of psychoneurology.
Biography. Vygotsky grew up in pre-revolutionary Russia in Gomel, Belorussia, as the second child in a Jewish family of eight children. His parents stimulated the children’s interest in the belles-lettres, and prose, poetry, and theater remained Vygotsky’s passion throughout his life. Having finished the gymnasium in Gomel, Vygotsky moved to Moscow to study law at Moscow State University. At the same time, he studied a broad curriculum of courses in the humanities, plus psychology, at the unofficial Shanyavsky University. During his university years Vygotsky missed no opportunity to attend the performances at Alexander Tairov’s Chamber Theater and Konstantin Stanislavsky’s Art Theater. Stanislavsky’s and Edward Gordon Craig’s staging of Shakespeare’s Hamlet (December 1911–March 1914) deeply impressed Vygotsky and influenced his own analysis of Hamlet, which was accepted as a master’s thesis at Shanyavsky University in the summer of 1917. As a student Vygotsky also wrote literary reviews for newspapers, a practice that he continued when he returned to Gomel after the October Revolution.
During the civil war, when Gomel was intermittently occupied by German, White, and Red troops, Vygotsky earned his living by giving private lessons. In 1920, he secured a job as an official responsible for the cultural life of the town. In that capacity, he contracted theater groups, delivered popular talks, organized poetry readings, and so on. He also began teaching literature and other subjects at various schools. Around this time Vygotsky became interested in the way the formal properties of a text evoke aesthetic experiences in the reader. This led him to renew his study of psychology and to conduct some empirical investigations.
In 1924, Vygotsky received an invitation to work as a psychologist at Moscow University under the Marxist Konstantin Kornilov. Vygotsky’s doctoral dissertation, “The Psychology of Art” (1925), was based on a reworking of his master’s thesis on Hamlet and on his thinking about literary form, but he soon demonstrated that his interests were much broader. Vygotsky began working at various clinics as a clinical psychologist with mentally disturbed and physically handicapped children; he taught at various institutes and universities, worked for publishing houses, became the editor of scientific journals, supervised doctoral dissertations, and wrote hundreds of papers and books. He quickly became a prominent figure in Soviet psychology—one of the new young professors committed to the Marxist cause—and was acquainted with such high officials as the minister of education, Anatoliy Lunacharsky, and Lenin’s wife, Nadezhda Krupskaya, deputy to Lunacharsky.
In the spring of 1934, after ten years of frenetic activity as a psychologist, Vygotsky suffered a major attack of tuberculosis, the disease that had haunted him for the better part of his adult life, and he died at the age of thirty-seven, leaving a wife and two daughters. For reasons that defy rational explanation, his theories soon fell into political disgrace, and for decades it was impossible to refer to his writings. It was only with the republication in the late 1950s of some of his writings that his work became available once again. Still later these were translated from Russian into English, which unexpectedly led to Vygotsky’s sudden popularity in the Western world.
Cultural Psychology. In the late 1920s, Vygotsky developed his cultural-historical theory of the higher mental functions. In this theory he made a distinction between lower mental functions, which are innate and which humans share with kindred animals, and higher mental functions, which are based on the mastery of cultural tools. For example, both chimpanzees and human beings have memory for locations, objects, and so on. This is a lower mental function. But only humans have memory based on the cultural tools of language and literacy. In order to remember things, they can categorize them, write down a list, and form an intention—all acts that are heavily language-based. The same holds true for other mental functions such as vision.
What Vygotsky claimed, then, was that the specifically human mental processes are based upon the acquisition of cultural tools that were invented in the history of humankind. This viewpoint led him to explore how children’s cognitive functioning changes as they master the cultural tools of their culture. Vygotsky also drew the logical conclusion from his theory that the cognition of people from different cultures may be fundamentally different, and he was among the first to investigate the thinking of non-Western people. His finding that the people living in Uzbekistan categorized and thought in a different way (Luria, 1976) has been repeatedly confirmed in subsequent investigations with other populations (Scribner and Cole, 1981). Vygotsky drew the conclusion that it may be misleading to investigate the mental functioning of people from other (sub)cultures with tests that have been validated for a certain (i.e., affluent, Western) population.
In the late twentieth century, an increasing number of psychologists came to accept Vygotsky’s ideas, and the new field of cultural psychology, the study of the culture’s role in the mental life of human beings, emerged (Cole, 1996). For example, researchers may investigate whether the invention of the personal computer and word processing programs (both examples of modern cultural tools) changed the style of writing, or whether becoming literate makes one better at reasoning tasks (Scribner and Cole, 1981). One of the outcomes of such research is that modern psychological literature, previously largely based on data found in experiments with Western adolescents, with the assumption that they were universal, has come to pay much more attention to cultural variations in behavior and cognitive processes.
Dynamic Assessment. Although Vygotsky was skeptical about the use of mental tests, he thought they could be of diagnostic value if used in a proper way. In the early 1930s, he linked up with existing international research and advocated the dual testing of intelligence. In his view, the traditional IQ measurement does not yield enough information. A traditional IQ test measures what a child can do independently, the skills and knowledge the child has mastered. However, it is more revealing to test the child another time, to give him or her prompts and hints, and then to see to what extent he or she is able to profit from this assistance. Vygotsky predicted that some children would be able to profit from help much more than others and that these children would develop faster in the near future. The difference between independent test scores and assisted test scores indicates what Vygotsky called the child’s zone of proximal development.
Vygotsky saw the dual-testing procedure as a means to fine-tune school instruction to the individual child’s abilities, but in the Soviet Union the massive use of mental tests in schools proved rather short-lived; on the basis of their test scores, too many children from various minorities were referred to special schools. The authorities decided not to improve the tests but to prohibit their use. When Vygotsky’s writings became available in the West, the idea of dual testing struck a cord with psychologists working with learning-disabled children. Various researchers began developing dual tests, taking into
account contemporary demands for standardization and methodological rigor.
These investigations led to the new subdiscipline of dynamic testing (Sternberg and Grigorenko, 2002). Although in the early 2000s much remained to be done to improve the quality of research, a few preliminary conclusions could be drawn. First, Vygotsky’s hunch that a dual-testing procedure may be more informative than the traditional single-testing procedure seems valid. Children who score approximately the same on traditional IQ tests differ in their ability to profit from assistance. In different investigations the researchers have distinguished those who gain much from help and those who gain little. It is thought that the first group may be simply culturally deprived, whereas the second group may have organic problems. There is also evidence that school results can be predicted better on the basis of the dual-testing procedure than on the basis of the old static IQ test. Second, if the above proves true, the dual-testing procedure may be fairer to the individual child. For example, children who are able to profit from assistance may be offered enrichment programs that may enable them to attend regular schools rather than special ones (Van der Veer, 2007).
Education. One reason why Vygotsky insisted that children should be tested twice was that he believed that instruction co-determines cognitive development. In his opinion, teachers should offer a level of instruction that is slightly beyond the child’s level of individual performance but still lies within his or her zone of proximal development. That is, teachers should not wait until the child is supposedly ready for certain tasks but should offer problems that the child can solve only in cooperation with a more able peer or adult. Stimulated by these problems and the assistance offered, the child will realize the next phase in his or her cognitive development.
Vygotsky believed that instruction in elementary school leads the child to reflect on his or her own mental operations and to use them deliberately and efficiently. His favorite example was that of learning to write a letter. Letter writing requires the child to spell out information that the recipient may not have. One cannot write “When I stood there he laughed at me,” because the words “there” and “he” have no specific meaning outside the context— hence the need to carefully consider what the recipient needs to know. The writing of a letter also requires a conscious plan. In these respects letter writing is different from oral speech, but Vygotsky believed that training in letter writing led children to speak more deliberately and efficiently as well. Just like learning mathematical rules ideally makes one a more deliberate and efficient calculator, exercise in letter writing should make one a more deliberate and efficient speaker.
At secondary school Vygotsky recommended the teaching of what he called scientific concepts. Scientific concepts form a system that covers the essential relationships in a certain domain of knowledge. Scientific concepts should be distinguished from the everyday concepts that the child acquires independently or in interaction with peers and parents. For example, the child’s everyday concept of a king may focus on the king’s clothes and his supposed power. Likewise, the child’s everyday concept of a farmer may concern his appearance and the fact that he has cute animals. The scientific concept of a king would involve knowledge about different monarchies and other forms of government. The scientific concept of a farmer would involve such interconnected notions as turnover, demand, supply, costs, profit, and market. Characteristic of scientific concepts is not only that they cover the non-accidental, genuine aspects of reality, but also that they form a systemic, interconnected whole. Vygotsky believed that everyday and scientific concepts should enrich each other (the everyday concepts giving body and flesh to the abstract scientific concepts), but he attached a leading role to the scientific concepts. Ideally, the mastery of scientific concepts should lead to a scientific way of thinking that spreads to the child’s everyday thinking.
Vygotsky’s global ideas have inspired many researchers to develop new instructional programs. A typical approach is to introduce children to the core concepts (scientific concepts) and essential relationships within a knowledge domain with the help of graphs and symbols that graphically depict them. The children are then taught to use these graphs and symbols independently as cultural tools that guide their thinking process. Often, the researchers link up to Vygotsky’s idea that cognitive development relies to a considerable extent on the child’s interaction with more able peers and adults, stressing the importance of extensive classroom discussion. However, it is difficult to give general characterizations, because current Vygotsky-inspired educational investigations may differ widely (Kozulin, 2003; Moll, 1990).
Psycholinguistics. Strange as it may sound, Vygotsky considered language (or “speech,” in his terminology) to be the most fundamental cultural tool. The original function of speech is communication between persons, but fairly soon speech begins to serve intrapersonal goals. Take the example of a toddler who must learn to cross the street safely. In a first stage, the parent will tell the child to watch to the right and to the left, and the child will just follow these instructions. In other words, the child’s behavior is regulated or guided by the speech of the social other. In the next stage, the child will tell himself aloud to watch the left and the right and thus will effectively instruct himself how to behave properly. This may be termed a form of external self-regulation of one’s behavior (Wertsch, 1985). In the last stage, the child will merely think the instructions. In other words, the child has shifted to internal self-regulation of his behavior. It is important to note that in this development may be distinguished two transitions, so to speak: the transition from social behavior to individual behavior, and the transition from outer to inner behavior. One can speak of a transition from social behavior to individual behavior, because a process that was originally shared between two persons, an interpsychological process, has turned into an individual, intrapsychological process. The child is applying to himself what first was applied to him by others and has thereby mastered his own behavior through the use of speech. One can speak of a transition from outer to inner behavior, because gradually external, audible speech is replaced by inner speech or thinking. Vygotsky’s claim that speech develops in an interpersonal situation and subsequently is used to steer the self received additional support through his discussion of the phenomenon of egocentric speech. Jean Piaget first described the phenomenon of children who during play speak to themselves in a way that is often not intelligible to others. Piaget hypothesized that such speech is unintelligible because young children are unable to take the other’s point of view, that is, they are egocentric. Only gradually do children learn to replace their egocentric speech by social speech.
Vygotsky criticized Piaget’s contention and carried out several little experiments to refute Piaget’s views. Vygotsky noted, for example, that egocentric speech is absent or greatly reduced when the child is alone or surrounded by deaf children. This suggests that egocentric speech is meant as social communication. Vygotsky observed that the incidence of egocentric speech rises when the child is confronted with unexpected problems. This suggests that egocentric speech has some function in the solution of problems. Finally, Vygotsky noticed that egocentric speech becomes less intelligible as children grow older. From these results Vygotsky drew the conclusion that so-called egocentric speech originates in normal, communicative speech and branches off at a later stage; has as its function to steer the child’s behavior when the need arises; and becomes less and less intelligible for the outsider until it has become proper inner speech. According to Vygotsky, then, egocentric speech is an intermediary stage between normal, communicative speech and inner speech. Like communicative speech, it is audible, and like inner speech, it serves to guide the child’s thinking. Vygotsky’s arguments have inspired an enormous and still growing amount of research that cannot be summarized here. A useful overview of some trends can be found in Zivin (1979).
Psychoneurology. Throughout his scientific career, Vygotsky worked as a clinical psychologist with patients with mental disabilities and physical handicaps. Over the years, he and his collaborator Alexander Luria became increasingly interested in the brain organization of mental processes. To deepen their insight, both Vygotsky and Luria (being professors of psychology) began studying medicine at the Medical Faculty of the Psychoneurological Institute in Kharkov in 1931. At the time, the brain was considered a static structure, but Vygotsky came to believe that the brain is a flexible, dynamic system. In the words of Oliver Sacks, one of the elaborators of Vygotsky’s ideas: “We need a new view of the brain, a sense of it not as programmed and static, but rather as dynamic and active, a supremely efficient adaptive system geared for evolution and change, ceaselessly adapting to the needs of the organism” (1995, p. xvii).
The outlines of such a dynamic and systemic view were sketched by Vygotsky in the early 1930s. He argued that the brain organization of mental processes must be different in children and adults, and that mental processes are handled not by strictly localized centers but by brain systems. Take the case of an infant handling a doll. The handling will simultaneously stimulate the brain centers for smell, touch, and vision. Because of this simultaneous stimulation, these different parts will grow connections and form a circuit or system. As the child grows older, he will also learn the word “doll,” which means that the system will grow an additional link to the brain parts responsible for language. Thus, one and the same activity will lead to different activation patterns in the brain, depending on the age of the subject. This is the dynamic part of Vygotsky’s view. But the brain parts also hang together as a system, which often makes compensation possible. For example, when vision is damaged and the subject cannot produce the name of an object by looking, smell or touch can often do the work. Hence, different trajectories or connections within a system can compensate for each other. Vygotsky discussed the case of patients suffering from Parkinson’s disease (1997, p. 105). Such patients may no longer be able to initiate voluntary movements such as walking. But they can walk by stepping on pieces of paper laid on the floor. Sacks (1982, p. 316) describes another Parkinson patient who could only begin walking by shouting “Now!” at herself. In Vygotsky’s analysis, the point is that walking again becomes possible, because the patients use external signs to influence their own behavior. The patient as it were influences himself from the outside when some inner connection has gone awry. “The Parkinsonian patient establishes a connection between different parts of his brain through a sign, influencing himself from the periphery,” said Vygotsky (1997, p. 106). In a way, then, the patient may be resorting to an ontogenetically prior modus operandi, that of external self-regulation.
Such intriguing observations and insights were elaborated after Vygotsky’s death by Luria. He and his collaborators investigated countless patients with brain lesions and devised compensatory means for patients with severe disturbances. Together they developed the new discipline of neuropsychology of which Sacks became one of the main proponents. Vygotsky’s original ideas may have been rather global and oversimplified, but he was one of the first to see that the brain is a flexible, dynamic system that is crucially influenced by the cultural tools one masters, notably language (Luria, 1961).
Boring (1950) observed that historical recognition of the importance of a thinker depends in part on the successors of that thinker who defend and elaborate his or her theory. In the early 2000s Vygotsky acquired such successors in the West. An early 2000s’ inventory ranked him among the one hundred most eminent psychologists of the twentieth century (Haggbloom et al., 2002). Such an assessment must mean that twenty-first century researchers felt inspired by Vygotsky’s approach and believed that the issues Vygotsky addressed remain topical. In other words, Vygotsky belonged to the small group of researchers in the history of psychology who really mattered.
In English, the most complete bibliography of Vygotsky’s writings can be found in Van der Veer and Valsiner, 1991, cited below. The six volumes of The Collected Works of L.S. Vygotsky, published by Plenum Publishers, provide a good idea of Vygotsky’s theories but are not complete. Omitted are, among other things, the early writings on literature and art and several psychological monographs.
WORKS BY VYGOTSKY
“Thought and Speech.” In Psycholinguistics, edited by Sol Saporta. New York: Holt, Rinehart & Winston, 1961.
With Alexander R. Luria The Role of Speech in the Regulation of Normal and Abnormal Behavior. Oxford: Pergamon Press, 1961.
Thought and Language. Cambridge, MA: MIT Press, 1962.
“The Problem of Learning and Mental Development at School Age.” In Educational Psychology in the USSR, edited by Brian Simon and Joan Simon. London: Routledge & Kegan Paul, 1963.
With Alexander R. Luria. Cognitive Development: Its Cultural and Social Foundations. Cambridge, MA: Harvard University Press, 1976.
Rieber, Robert W., ed. The Collected Works of L. S. Vygotsky. 6 vols. New York: Plenum Press, 1987–1999.
“On Psychological Systems.” In The Collected Works of L. S. Vygotsky. Vol. 3: Problems of the Theory and History of Psychology, edited by Robert W. Rieber and Jeffrey Wollock. New York: Plenum Press, 1997.
Boring, Edwin G. A History of Experimental Psychology. New York: Appleton-Century-Crofts, 1950.
Cole, Michael. Cultural Psychology: A Once and Future Discipline, Cambridge, MA: The Belknap Press of Harvard University Press, 1996. Interesting overview of the field of cultural psychology.
Haggbloom, Steven J., Renee Warnick, Jason E Warnick, et al. “The 100 Most Eminent Psychologists of the 20th Century.” Review of General Psychology 6 (2002): 139–152.
Kozulin, Alex. Vygotsky’s Psychology: A Biography of Ideas. New York: Harvester Wheatsheaf, 1990. Excellent presentation and interpretation of Vygotsky’s major ideas.
Kozulin, Alex, Boris Gindis, Vladimir S. Ageyev, and Suzanne M. Miller, eds. Vygotsky’s Educational Theory in Cultural Context. Cambridge, U.K.: Cambridge University Press, 2003.
Lloyd, Peter, and Charles Fernyhough, eds. Lev Vygotsky: Critical Assessments. 4 vols. London: Routledge, 1999.
Moll, Luis, ed. Vygotsky and Education: Instructional Implications of Sociohistorical Psychology. New York: Cambridge University Press, 1990.
Sacks, Oliver. Awakenings. London: Picador, 1982.
———. An Anthropologist on Mars: Seven Paradoxical Tales. New York: Alfred A. Knopf, 1995.
Scribner, Sylvia, and Michael Cole. The Psychology of Literacy. Cambridge, MA: Harvard University Press, 1981.
Sternberg, Robert J., and Elena L. Grigorenko. Dynamic Testing. New York: Cambridge Unversity Press, 2002.
Van der Veer, René. “Vygotsky’s Educational Thinking.” In Biographical Encyclopedia of Educational Thought. Vol. X, edited by Richard Bailey. London and New York: Continuum Publishers, 2007.
Van der Veer, René, and Jaan Valsiner. Understanding Vygotsky: A Quest for Synthesis. Oxford, U.K.: Blackwell, 1991. The most comprehensive historical analysis of the development of Vygotsky’s theories.
Wertsch, James V. Vygotsky and the Social Formation of Mind. Cambridge, MA: Harvard University Press, 1985. In-depth analysis of Vygotsky’s work with the focus on his psycholinguistic ideas.
Zivin, Gail, ed. The Development of Self-Regulation through Private Speech. New York: John Wiley, 1979.
René van der Veer
"Vygotsky, Lev Semyonovich." Complete Dictionary of Scientific Biography. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/vygotsky-lev-semyonovich
"Vygotsky, Lev Semyonovich." Complete Dictionary of Scientific Biography. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/vygotsky-lev-semyonovich
Vygotsky, L. S. (1896–1934)
Vygotsky, L. S. (1896–1934)
Lev Semyonovich Vygotsky grew up in a Jewish family in Gomel in Belorussia (now known as Belarus). After a traditional Jewish education, he was admitted to the law school at Moscow University, but he also took courses in history and philosophy. In 1916 he wrote a master's thesis analyzing Shakespeare's Hamlet. In 1917 he returned to Gomel as a teacher and also practiced clinical psychology. Here he wrote Educational Psychology and his dissertation, The Psychology of Art.
In 1924, at a congress in Leningrad, Vygotsky presented a talk on consciousness. Due to the success of the talk, he gained access to the Kornilov Institute of Experimental Psychology in Moscow. Here, together with Alexander Luria and Alexei Leontiev, he developed the cultural-historical theory as an answer to the crisis in psychology. In The Historical Meaning of the Crisis in Psychology, written between 1925 and 1927, Vygotsky argued that there was no unity or consistency in contemporary psychological research. He claimed that it was difficult to see how the psychoanalytic view of human nature and Pavlov's theory on human behavior could be bridged and that Marxist psychology only pieced together quotations from Karl Marx and Friedrich Engels.
In his 1931 work, The History of the Development of Higher Psychological Functions, Vygotsky outlined the idea that psychological development can be seen as the transition from natural forms of behavior to higher mental functions that have a mediated structure. Signs, symbols, and languages function as mediators and create this psychological structure. With this cultural-historical approach, changes in psychological processes can be related to changes in the social-cultural type of mediation. Simultaneously, higher mental processes have to be seen as functions of meaningful social activity created through the individual's own activity. He also formulated the concept of the zone of proximal development–that is, the difference between actual achievement (tasks a child can perform on his or her own) and potential achievement (tasks a child can perform with help from another)–which has inspired pedagogues to reflect on the relation between learning and development and between play and teaching.
Vygotsky investigated the development of and the relation between thinking and language, and he described language as a mental tool for thinking. He dictated his manuscript on this topic from his sickbed and it was published in 1934 as Thought and Language, which became his most popular book.
He left behind an extensive and still highly regarded body of scientific work. Most of it was not published in his lifetime, and two years after his death in 1936 his few available publications were blacklisted in the Soviet Union. In 1956 Vygotsky was rehabilitated, but almost twenty years passed before his genius was known and his work adopted in the rest of the world. Vygotsky has had an enormous influence on psychological and educational thinking and practice around the world. Thus the American Vygotsky expert Stephen Toulmin praised Vygotsky for his talents, genius, and sumptuous production and called him the Mozart of psychology.
See also: Child Development, History of the Concept of; Child Psychology.
Toulmin, Stephen. 1978. "The Mozart of Psychology." New York Review of Books 28: 51–57.
Van der Veer, René, and Jaan Valsiner. 1991. Understanding Vygotsky: A Quest for Synthesis. Oxford, UK: Blackwell.
Vygotsky, Lev S. 1971. The Psychology of Art. Cambridge, MA: MIT Press.
Vygotsky, Lev S. 1978. Mind in Society: The Development of Higher Psychological Processes. Cambridge, MA: Harvard University Press.
Vygotsky, Lev S. 1986. Thought and Language. Cambridge, MA: MIT Press.
Vygotsky, Lev S. 1997. "The Historical Meaning of the Crisis in Psychology: A Methodological Investigation." In Problems of the Theory and History of Psychology: Vol. 3. The Collected Works of L.S. Vygotsky. New York: Plenum Press.
Vygotsky, Lev S. 1997. Educational Psychology. Boca Raton, FL: St. Lucie Press.
"Vygotsky, L. S. (1896–1934)." Encyclopedia of Children and Childhood in History and Society. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/children/encyclopedias-almanacs-transcripts-and-maps/vygotsky-l-s-1896-1934
"Vygotsky, L. S. (1896–1934)." Encyclopedia of Children and Childhood in History and Society. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/children/encyclopedias-almanacs-transcripts-and-maps/vygotsky-l-s-1896-1934
Vygotsky, Lev Semyonovich
Lev Semyonovich Vygotsky, 1896–1934, Russian psychologist. His most productive years were at the Institute of Psychology in Moscow (1924–34), where he expanded his ideas on cognitive development, particularly the relationship between language and thinking. His writings emphasized the roles of historical, cultural, and social factors in cognition and argued that language was the most important symbolic tool provided by society. His Thought and Language (1934) is a classic text in psycholinguistics.
See J. V. Wertsch, Vygotsky and the Social Formation of Mind (1985).
"Vygotsky, Lev Semyonovich." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (December 15, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/vygotsky-lev-semyonovich
"Vygotsky, Lev Semyonovich." The Columbia Encyclopedia, 6th ed.. . Retrieved December 15, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/vygotsky-lev-semyonovich