In 1912, in his presidential address to the First International Congress of Eugenics, a landmark gathering in London of racial biologists from Germany, the United States, and other parts of the world, Major Leonard Darwin, Charles Darwin’s son, trumpeted the spread of eugenics and evolution. As described by Nicholas Wright Gillham in his A Life of Francis Galton, Major Darwin foresaw the day when "eugenics would become not only a grail, a substitute for religion, as Galton had hoped, but a 'paramount duty' whose tenets would presumably become enforceable." The major repeated his father’s admonition that, though the crudest workings of natural selection must be mitigated by "the spirit of civilization," society must encourage breeding among the best stock and prevent it among the worst "without further delay."
Leonard Darwin’s recognition of his father’s role in the formation and promotion of eugenics was more than filial piety. Though Charles Darwin usually preferred the savannas of research to the sierras of philosophic speculation, he was a main player in the "transvaluation of values," including the advancement of theories every bit as hard and merciless as Nietzsche’s. Adrian Desmond and James Moore in their 1991 biography, Darwin: The Life of a Tormented Evolutionist, make clear that natural selection was intended as more than a theory of life’s origins. "'Social Darwinism' is often taken to be something extraneous, an ugly concretion added to the pure Darwinian corpus after the event, tarnishing Darwin’s image," they write. "But his notebooks make plain that competition, free trade, imperialism, racial extermination, and sexual inequality were written into the equation from the start-Darwinism was invented to explain human society."
Peter Quinn, The Gentle Darwinians
The distinction between the good "gentle Darwin" and the evil, science-twisting social Darwinists is not so clear as pop-science hagiography often claims. Alas.