Gestalt psychology-Hereditary psychology-Twin research: Kurt Gottschaldt (1902-1991) and the German-Japanese knowledge transfer during national socialism and the postwar period.

The present article reconstructs the scientific career of the psychologist Kurt Gottschaldt (1902-1991) in the context of the Kaiser Wilhelm Institute for Anthropology, Human Heredity, and Eugenics (Kaiser-Wilhelm-Institut für Anthropologie, menschliche Erblehre und Eugenik [KWI-A]) in Berlin, Germany. Against this background, it aims to analyze the scope and characteristics of the German-Japanese knowledge transfer during National Socialism and the postwar period. Drawing on Gottschaldt's profile as a Gestalt psychologist, the article establishes that his work at the KWI-A marked a programmatic reorientation toward hereditary psychology and twin research. The twin method functioned as an empirical instrument for quantifying the relationship between "heredity" and "environment" and was embedded within the institute's racial-scientific research program. The transnational dimension of this research is reconstructed for the first time through the cases of the Japanese visiting scholars Takagi Masataka (1913-1962?) and Kamitake Masaji (1909-1983). Their work documents both their institutional integration into the KWI-A as well as the lasting influence of the theoretical and methodological concepts developed there on Japanese psychology after 1945. The article demonstrates that key personnel networks, methodological approaches, and epistemological principles persisted despite the political rupture. In doing so, the study contributes to a nuanced examination of the entanglement of science, politics, and international exchange in the 20th century. (PsycInfo Database Record (c) 2026 APA, all rights reserved).