Köhler Wolfgang (1887–1967), German and American (after 1935) psychologist who, with Wertheimer and Koffka, founded Gestalt psychology. Köhler made two distinctive contributions to Gestalt doctrine, one empirical, one theoretical. The empirical contribution was his study of animal thinking, performed on Tenerife Island from 1913 to 1920 (The Mentality of Apes, 1925). The then dominant theory of problem solving was E. L. Thorndike’s (1874–1949) associationist trial-and-error learning theory, maintaining that animals attack problems by trying out a series of behaviors, one of which is gradually ‘stamped in’ by success. Köhler argued that trial-and-error behavior occurred only when, as in Thorndike’s experiments, part of the problem situation was hidden. He arranged more open puzzles, such as getting bananas hanging from a ceiling, requiring the ape to get a (visible) box to stand on. His apes showed insight – suddenly arriving at the correct solution. Although he demonstrated the existence of insight, its nature remains elusive, and trial-and-error learning remains the focus of research.
Köhler’s theoretical contribution was the concept of isomorphism, Gestalt psychology’s theory of psychological representation. He held an identity theory of mind and body, and isomorphism claims that a topological mapping exists between the behavioral field in which an organism is acting (cf. Lewin) and fields of electrical currents in the brain (not the ‘mind’). Such currents have not been discovered. Important works by Köhler include Gestalt Psychology (1929), The Place of Value in a World of Facts (1938), Dynamics in Psychology (1940), and Selected Papers (1971, ed. M. Henle). See also FIGURE – GROUND. T.H.L.