The growing importance of the biological sciences in the nineteenth century, following the discoveries of Charles Darwin, led most scientists to advance theories of human inequality as matters of scientific fact.Read more here
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Eugenics developed within the larger movement of Social Darwinism, which applied Darwin's "struggle for survival" to human affairs.
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In 1923 the University of Munich appointed Lenz to the first German chair in race hygiene, and after Hitler assumed power, Lenz occupied the race hygiene chair in Berlin. In 1931, two years before Hitler's assumption of power, Lenz provided the Nazi leader with the following testimonial: "Hitler is the first politician with truly wide influence who has recognized that the central mission of all politics is race hygiene and will actively support this mission."