Hugo Dingler, the German philosopher of science, was the most important representative of Continental operationism, as distinguished from the operationalism of the American physicist P. W. Bridgman. Dingler was also a main contributor to Grundlagenforschung (research on the foundations of the exact sciences). After studying under such teachers as David Hilbert, Edmund Husserl, Felix Klein, Hermann Minkowski, Wilhelm Röntgen, and Woldemar Voigt at the universities of Erlangen, Munich, and Göttingen, Dingler received a Ph.D. in mathematics, physics, and astronomy in 1906 and became Privatdozent in 1912. He was appointed professor at the University of Munich in 1920 and at the Technische Hochschule in Darmstadt in 1932. In 1934 he was dismissed on charges of philosemitism. He later resumed teaching but soon rebelled again against the political situation, and eventually he was put under the continuous watch of a Gestapo agent "who unfortunately"—as Dingler told the...