THORNDIKE, EDWARD LEE (1874- 1949)

Thorndike, a pioneer in educational psychology, was bom in Massachusetts, and received his B.A. degree at Wesleyan, his M.A. at Harvard, and his Ph.D. at Columbia. At Harvard he was greatly influenced by William James, who allowed him to use his house to incubate, hatch and test chicks for use in experiments on animal intelligence. These investigations were continued at Columbia under J. M. Cattell’s supervision, and provided the subject matter for his doctoral thesis.The importance of this experimental work cannot be overestimated, for it offered a quantitative analysis of human learning, as opposed to the anecdotal, descriptive accounts on which previous studies depended. Thorndike set up the classic “puzzle-box” situation in which the animal could open his cage and obtain a reward only by performing an operation or a series of operations such as clawing a rope or moving a latch. His experiments with this device are regarded as the first laboratory study of animal learning. By measuring the time taken in repeated performances, he found that the learning curves of animals were quite similar to those discovered by Hermann Ebbinghaus for human beings.Thorndike termed this type of learning “trial and error,” and showed thatit applied to higher animals (monkeys) as well as lower. The results of these experiments (which were later recorded in book form in Animal Intelligence, 1911) helped to combat the widespread notion that animals learn only through observation and imitation. His techniques were criticized by members of the Gestalt school, who argued that the puzzle-box tasks could not, by their nature, show that animals are capable of insight. Nevertheless, he held to his position and at the suggestion of Cattell applied his procedures to the study of thought processes of children and young people. As a result of this work, he developed a learning theory which he called “connectionism,” propounding it in Educational Psychology (1903), Elements of Psychology (1904), and Mental and Social Measurements (1904).In essence, the connectionist theory holds that when we learn we establish connections termed “S-R bonds” between stimuli and responses. Two basic laws apply to this process: (1) the law of exercise, which states that the bonds are strengthened by repetition and weakened by disuse: and (2) the law of effect, which states that the bonds are strengthened by satisfaction and weakened by punishment or other negative effects. The bonds themselves were conceived in terms of synaptic activity.Throughout his life, Thorndike kept experimenting on learning and revised some of his views on the process—for example, he came to believe that punishment does not break a bond, though it does affect motivation and tends to discourage the leamer from further activity. This view helped to cut down on the use of punishment in correcting deviant behavior; it also focused greater attention on the importance of rewards (both verbal and material) in “stamping in” the connections. Further studies showed that reward—such as having the experimenter say “Right”—tend to “spread” both backwards and forwards, reinforcing the learning that has just occurred as well as the learning that takes place immediately afterward. Thorndike was a remarkably prolific investigator, and a brief biography can only indicate the general scope of his achievements. Practically all of his work was done at Columbia University, where he served as professor of psychology and head of the Institute of Educational Research. In his early period he made a number of outstanding contributions in addition to those noted above. He wrote one of the first layman’s books on psychology, The Human Nature Club; performed the first controlled study of twins, showing that they were far more similar in their performances on mental tests than ordinary siblings; promoted the use of the Binet-Simon scales in the school system; and carried out pioneer investigations of transfer of training with R. S. Woodworth, proving that a study of mathematics and Latin does not automatically improve learning ability in all subjects. During his next period, starting in 1911, he revised and enlarged his books on educational psychology and mental measurements, showed how statistical procedures could be applied to educational problems, and developed scales for the appraisal of drawing and handwriting. Between 1916 and 1920 Thorndike devoted himself to the war. He wrote on military psychology, helped to devise the Army Alpha and Beta tests, investigated the effects of ventilation and humidity on the work curve, and published eight educational tests. In the 1920s he published On Adult Learning, Elementary Principles of Education, and The Measurement of Intelligence, all with associates. During the 1930s he wrote on the psychology of learning, with special reference to algebra and arithmetic (Fundamentals of Learning, 1932). He then launched his monumental projects in lexicography, including his THUMBSUCKING Teacher’s Workbook, which gives the relative frequency of thirty thousand English words, and his Thorndike-Cen- tury Junior Dictionary, in which the definitions are given in words frequently used by children. In his later years he turned to the wholly different and wholly new field of studying and measuring the characteristics of cities and states, publishing Your City in 1939 and American Cities and States in 1942. His final psychological work was Human Nature and the Social Order (1940). Thorndike’s impact on educational psychology was, and is, widely felt. His leadership was recognized by his colleagues, who elected him president of the American Psychological Association in 1912 and president of the American Association