| Edward Chace Tolman | |
|---|---|
| Born | April 14, 1886 West Newton, Massachusetts |
| Died | November 19, 1959 |
| Nationality | American |
| Fields | psychologist |
| Known for | behavioral psychology purposive behaviorism |
Edward Chace Tolman (April 14, 1886 – November 19, 1959) was an American psychologist. He was most famous for his studies on behavioral psychology.
Born in West Newton, Massachusetts, brother of CalTech physicist Richard Chace Tolman, Edward C. Tolman studied at the Massachusetts Institute of Technology, and received his Ph.D. from Harvard University in 1915. Most of his career was spent at the University of California, Berkeley (from 1918 to 1954), where he taught psychology. Tolman's father was a president of a manufacturing company and his mother was adamant of her Quaker background [1]. Tolman attended MIT because of family pressures, but after reading William James' "Principles of Psychology" he decided to abandon physics, chemistry, and mathematics in order to study philosophy and psychology [2]. He enrolled in Harvard and worked in the laboratory of Hugo Munsterburg[3]. James' influence on Tolman could be seen in Tolman's courageous attitude and his willingness to cope with issues that cause controversy and are against the popular views of the time. Tolman always said he was strongly influenced by the Gestalt psychologists, especially Kurt Lewin and Kurt Koffka [4].
Tolman is best known for his studies of learning in rats using mazes, and he published many experimental articles, of which his paper with Ritchie and Kalish in 1946 was probably the most influential. His major theoretical contributions came in his 1932 book, Purposive Behavior in Animals and Men, and in a series of papers in the Psychological Review, "The determinants of behavior at a choice point" (1938), "Cognitive maps in rats and men" (1948) and "Principles of performance" (1955).[5][6][7][8][9][10]
Although Tolman was firmly behaviorist in his methodology, he was not a radical behaviorist like B. F. Skinner. As the title of his 1932 book indicates, he wanted to use behavioral methods to gain an understanding of the mental processes of humans and other animals. In his studies of learning in rats, Tolman sought to demonstrate that animals could learn facts about the world that they could subsequently use in a flexible manner, rather than simply learning automatic responses that were triggered off by environmental stimuli. In the language of the time, Tolman was an "S-S" (stimulus-stimulus), non-reinforcement theorist: he drew on Gestalt psychology to argue that animals could learn the connections between stimuli and did not need any explicit biologically significant event to make learning occur. This is known as latent learning. The rival theory, the much more mechanistic "S-R" (stimulus-response) reinforcement-driven view, was taken up by Clark L. Hull.
A key paper by Tolman, Ritchie and Kalish in 1946 demonstrated that rats that had explored a maze that contained food while they were not hungry were able to run it correctly on the first trial when they entered it having now been made hungry. Learning the map the first time without having a reward was termed the latent learning period [11]. However, Hull and his followers were able to produce alternative explanations of Tolman's findings, and the debate between S-S and S-R learning theories became increasingly convoluted and sterile. Skinner's iconoclastic paper of 1950, entitled "Are theories of learning necessary?" persuaded many psychologists interested in animal learning that it was more productive to focus on the behavior itself rather than using it to make hypotheses about mental states. The influence of Tolman's ideas declined rapidly in the later 1950s and 1960s. However, his achievements had been considerable. His 1938 and 1955 papers, produced to answer Hull's charge that he left the rat "buried in thought" in the maze, unable to respond, anticipated and prepared the ground for much later work in cognitive psychology, as psychologists began to discover and apply decision theory - a stream of work that was recognized by the award of a Nobel prize to Daniel Kahneman in 2002. And his 1948 paper introduced the concept of a cognitive map, which has found extensive application in almost every field of psychology, frequently among scientists who have no idea that they are using ideas first formulated to explain the behavior of rats in mazes. Tolman assessed both response learning and place learning. Response learning is when the rat knows that the response of going a certain way in the maze will always lead to food; place is learning is when the rats learn to associate the food in a specific spot each time [12]. In his trials he observed that all of the rats in the place-learning maze learned to run the correct path within eight trials and that none of the response-learning rats learned that quickly, and some did not even learn it at all after seventy-two trials [13].
Furthermore, when in the last quarter of the twentieth century animal psychologists took a cue from the success of human cognitive psychology, and began to renew the study of animal cognition, many of them turned to Tolman's ideas and to his maze techniques. Of the three great figures of animal psychology of the middle twentieth century, Tolman, Hull and Skinner, it can reasonably be claimed that it is Tolman's legacy that is currently the liveliest, certainly in terms of academic research. He was elected a Fellow of the American Academy of Arts and Sciences in 1949.[14]
Tolman's theoretical model was described in his book "The Determiners of Behavior at a Choice Point" [15]. The three different variables that influence behavior are: independent, intervening, and dependent variables. The experimenter can manipulate the independent variables; these independent variables (e.g., stimuli provided) in turn influence the intervening variables (e.g., motor skill, appetite) [16]. Independent variables are also factors of the subject that the experimenter specifically chooses for. The dependent variables (e.g., speed, number of errors) allows the psychologist to measure the strength of the intervening variables [17].
Tolman was much concerned that psychology should be applied to try to solve human problems, and in addition to his technical publications, he wrote a book called Drives Toward War. He was one of the senior professors whom the University of California sought to dismiss in the McCarthyite era of the early 1950s, because he refused to sign a loyalty oath - not because of any lack of felt loyalty to the United States but because it infringed on academic freedom. Tolman was a leader of the resistance of the oath, and when the Regents of the University of California sought to fire him, he sued. The resulting court case, Tolman v. Underhill, led to the California Supreme Court in 1955 overturning the oath and forcing the reinstatement of all those who had refused to sign it; Tolman could be considered a hero. In 1963, at the insistence of the then President of the University of California Clark Kerr, the University named its newly constructed Education and Psychology faculty building at Berkeley "Tolman Hall" in his honor; his widow was present at the dedication ceremony. His portrait hangs in the entrance hall of the building.
Tolman won many awards and honors. He was president of the APA in 1937 and chairman of Lewin's Society for the Psychological Study of Social issues in 1940; he was a member of the Society of Experimental Psychologists and the National Academy of Sciences, and the APA gave him and award in 1957 for distinguished contributions [18].