* Of course, many of the Jewish scientists and mathematicians persecuted by the Nazis would not have regarded themselves as standard bearers for “diversity.” They considered themselves just as German as the fellow in the next office; their religious heritage loomed large only from the perspective of a racist ideology. Fritz Haber, for example, was baptized as a Christian and was a patriot, yet because of his Jewish ancestry suffered anti-Semitism even before the Nazis took control in Germany. (Haber, a Nobel laureate in chemistry, was responsible for one of the most wonderful inventions in history—a process for synthesizing nitrogen-based fertilizers, helping to feed the world—and one of the most terrible, the use of chlorine gas as a weapon of war.)

In part because of such discrimination, scientists of the time with Jewish heritage arguably were different. Haber, for example, struggled to find a professorship. Looking for a source of income elsewhere, he turned to industry, signing a contract with the optical firm Zeiss and aggressively pursuing patents. As a result, when he did eventually secure a professorial appointment, he had different contacts and a more practical outlook. His work on fertilizers followed from that problem-focused perspective, and it was work that changed the world.

The historian of science David Bodanis argues that the outlook of Germany’s Jewish scientists was also shaped by discrimination they had suffered elsewhere. Several of the mathematicians at Göttingen were originally Russian or Polish Jews who viewed the university as a safe harbor from persecution in their home countries. They had a distinctive training, and the contrast between the German, Polish, and Russian styles of mathematics was a great source of ideas.

It is possible, however, that the main effect Fabian Waldinger’s research is detecting is not the expulsion of people who had a different perspective because they had been pushed out of Poland or Russia, or been forced to sidestep discrimination by dabbling in industry—but simply the expulsion of scientists who were outstanding because they had to be. Only the very best would be able to overcome the disadvantage of biased appointment committees. “A fine example is Emmy Noether,” writes Bodanis (personal correspondence, February 2016). As a Jewish woman, Noether had to overcome a double dose of prejudice. “She really was stupendous . . . being ‘averagely brilliant’ would not have been enough.” Emmy Noether laughed when the first students started coming to class wearing Nazi brown shirts, but she was one of the first of Göttingen’s Jews to lose her job. With the help of Albert Einstein she secured a position at Bryn Mawr College near Philadelphia in 1933.