Karl Duncker, M.A.
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Well known Gestalt Psychologist. Source: Simon, H. Karl Duncker and Cognitive Science. Thinking in Psychological Science: Ideas and Their Makers (edited by Jaan Valsiner) - D Peterzell
M.A. 1926 from Clark U. "An experimental and theoretical study of productive thinking" signed by Nafe. In separate publications, King & Wertheimer, and Herb Simon, suggest that Wertheimer and Kohler had a strong influence on this work.
Ph.D. 1929 from U. Berlin (supervised by Wertheimer and Kohler)