For Weikart (a historian at California State University, Stanislaus), the two most important steppingstones that led from Darwin to Hitler were the biologist Ernst Haeckel and the philosopher Friedrich Nietzsche. But the real value of this riveting work of intellectual history comes from the minute tracing of the influence exerted on the German public by lesser-known figures who served as conduits for Darwinian ideas in specialized journals, newspapers, various academic and professional congresses, and the like. Relying on a prodigious amount of original research (including the private correspondence of many writers who recognized that some of their thinking was as yet too explosive to be voiced before the public in print), Weikart has provided a signal service not just to historical scholarship but also to the general public during this time when eugenics is being used to justify "therapeutic" abortions, post-natal infanticide and euthanasia.
Perhaps the greatest lesson to be drawn from Weikart's narrative is the astonishing metaphysical continuity he limns in the views that started with Darwin and ended up with Hitler. To trace this continuity, one need only compare this passage from Nietzsche's Will to Power with a similar one, immediately following, from Mein Kampf.
From Nietzsche:
The biblical prohibition "Thou shalt not kill" is a piece of naïveté compared with the seriousness of Life's own "Thou shalt not" issued to decadence: "Thou shalt not procreate!" —Life itself recognizes no solidarity, no "equal right," between the healthy and the degenerate parts of an organism… . Sympathy for the decadents, equal rights for the ill-constituted—that would be the profoundest immorality, that would be anti-nature itself as morality!
From Hitler:
A stronger race will supplant the weaker, since the drive for life in its final form will decimate every ridiculous fetter of the so-called "humaneness" of individuals, in order to make place for the true "humaneness of nature," which destroys the weak to make place for the strong.
Apologists for Nietzsche, when confronted with passages from Will to Power that sound so congruent to Mein Kampf, like to claim that this posthumously published work does not represent Nietzsche's true thinking because of the tendentious editing of his pro-Nazi sister. Perhaps so, but other passages from his published works show how consonant the views expressed here are with those he sent out into the public under his own name. In Thus Spake Zarathustra he said: "Far too many keep on living; they hang on their branches much too long. May a storm soon come, which shakes all this rotten and worm-eaten fruit from the tree!" In a section of The Gay Science entitled "Holy Cruelty," a Nietzschean "saint" advises a father to kill his disabled child, rhetorically asking, "Isn't it crueler to allow it to live?" The Twilight of the Idols includes a section entitled "Morality for Physicians" that calls sick people "parasites" who have no right to life and advocates the "most ruthless suppression and pushing aside of degenerate life." And finally in his autobiography Ecce Homo, one of the last books he sent to the publisher before his collapse into insanity, he said: "If we cast a look a century ahead and assume that my assassination of two thousand years of opposition to nature and of dishonoring humans succeeds, then that new party of life [!] will take in hand the greatest of all tasks—the higher breeding of humanity, including the unsparing destruction of all degenerates and parasites." The metaphysical and ethical continuity from these grim passages to Mein Kampf is seamless.






