Tolman, Edward

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Tolman, Edward 1886–1959

The American psychologist Edward Chace Tolman was born in Newton, Massachusetts, on April 14, 1886 and died in Berkeley, California, on November 19, 1959. He received a BS in electrochemistry from the Massachusetts Institute of Technology in 1911, and a PhD in experimental psychology from Harvard in 1915. He spent the bulk of his academic career at the University of California, Berkeley, retiring in 1954. In 1937 he was elected to the National Academy of Sciences.

Tolman entered psychology in the first years of John B. Watson’s behaviorist revolution, and he even dedicated his best-known book, Purposive Behavior in Animals and Men (1932), to the white rat, but he was never a radical behaviorist. Whereas Watson (and, later, B. F. Skinner) rejected mental states as explanatory constructs, Tolman emphasized molar behavior over molecular “muscle-twitches,” as well as the importance of goals and expectations intervening between stimulus and response. (Another neobehaviorist, Clark Hull, similarly stressed the importance of internal drive states.) Heavily influenced by Gestalt theory, and especially by Kurt Lewin’s notion of the “life-space,” Tolman viewed the behaving organism as acquiring a “sign-gestalt-expectation” that a particular behavior will achieve a particular goal in a particular “behavior space,” and a general “means-end readiness,” represented by a “belief-value matrix” to engage in similar behavior in the future, under similar circumstances. He construed the rat facing a maze, even on the first learning trial, as entertaining and testing a sort of hypothesis as to what it should do; as engaged in “vicarious trial and error” behavior as it considered the choice of turning right or left; and as actively “searching for the stimulus” that would indicate one choice over another.

The flavor of Tolman’s experimental work, and its implications, are best illustrated by his most famous experiment, on “latent learning” (Tolman and Honzik 1930). Over twenty trials, rats who were rewarded with food took progressively less time to traverse a maze, compared to a control group that received no reward. A third group received no reward for the first ten trials, and behaved no differently than the controls. But when reward was introduced in trial eleven, they showed a precipitous drop in running time, behaving just like the rats who had been rewarded all along. Apparently, these rats had formed a “cognitive map” of the maze as a whole, but did not act on what they had learned until they had an incentive to do so. This experiment shattered the traditional view that reinforcement was crucial to learning: Reinforcement may control performance, but learning happens even in its absence. By redefining learning as the acquisition of knowledge, which organisms—rats as well as humans—could use for their own purposes, Tolman’s “purposive behaviorism” set the stage for the cognitive revolution in psychology that began in the 1950s.

Tolman was a civil libertarian as well as a psychologist, and served for a time on the national board of the American Civil Liberties Union. Perhaps reflecting his Quaker background, in 1918 he was dismissed from his first faculty post, at Northwestern University, for publishing an article in a pacifist student publication; and in 1942 he published Drives Towards War, proposing a set of social controls that could produce a warless society. Nevertheless, he volunteered for military service in World War I, and was offered a commission in the army; and he worked for the Office of Strategic Services, forerunner to the Central Intelligence Agency, during World War II. From 1949 to 1950 Tolman led faculty opposition to a loyalty oath required by the Regents of the University of California. He (among others) was briefly dismissed from his post, taking shelter at Harvard. In Tolman v. Underhill (1955) the California Supreme Court invalidated the oath, and Tolman and the others were reinstated. In 1963, in recognition of his contributions to both the discipline of psychology and the cause of academic freedom, the building housing Berkeley’s Department of Psychology and the School of Education—an award-winning example of mid-twentieth-century modernism designed by Gardner Dailey—was renamed in Tolman’s honor.

SEE ALSO Behaviorism; Civil Liberties; Gestalt Psychology; Hull, Clark; Peace; Psychology; Skinner, B. F.; War

BIBLIOGRAPHY

PRIMARY WORKS

Tolman, Edward C. 1932. Purposive Behavior in Animals and Men. New York: Century.

Tolman, Edward C. 1938. The Determinants of Behavior at a Choice Point. Psychological Review 45: 1–41.

Tolman, Edward C. 1942. Drives Towards War. New York: Appleton-Century-Crofts.

Tolman, Edward C. 1948. Cognitive Maps in Rats and Men. Psychological Review 55: 189–208.

Tolman, Edward C. 1952. Edward Chace Tolman. In A History of Psychology in Autobiography, vol. 4, eds. Edwin G. Boring, Herbert Werner, Heinz S. Langfeld, and Robert M. Yerkes, 323–339. Worcester, MA: Clark University Press.

Tolman, Edward C. 1955. Principles of Performance. Psychological Review 62: 315–326.

Tolman, Edward C., and Charles H. Honzik. 1930. “Insight” in Rats. University of California Publications in Psychology 4 (14): 215–232.