Nothing can be known about the future, thought Hitler, except the limits of our planet: “the surface area of a precisely measured space.” Ecology was scarcity, and existence meant a struggle for land. The immutable structure of life was the division of animals into species, condemned to “inner seclusion” and an endless fight to the death. Human races, Hitler was convinced, were like species. The highest races were still evolving from the lower, which meant that interbreeding was possible but sinful. Races should behave like species, like mating with like and seeking to kill unlike. This for Hitler was a law, the law of racial struggle, as certain as the law of gravity. The struggle could never end, and it had no certain outcome. A race could triumph and flourish and could also be starved and extinguished.

In Hitler’s world, the law of the jungle was the only law. People were to suppress any inclination to be merciful and were to be as rapacious as they could. Hitler thus broke with the traditions of political thought that presented human beings as distinct from nature in their capacity to imagine and create new forms of association. Beginning from that assumption, political thinkers tried to describe not only the possible but the most just forms of society. For Hitler, however, nature was the singular, brutal, and overwhelming truth, and the whole history of attempting to think otherwise was an illusion. Carl Schmitt, a leading Nazi legal theorist, explained that politics arose not from history or concepts but from our sense of enmity. Our racial enemies were chosen by nature, and our task was to struggle and kill and die.

“Nature,” wrote Hitler, “knows no political boundaries. She places life forms on this globe and then sets them free in a play for power.” Since politics was nature, and nature was struggle, no political thought was possible. This conclusion was an extreme articulation of the nineteenth-century commonplace that human activities could be understood as biology. In the 1880s and 1890s, serious thinkers and popularizers influenced by Charles Darwin’s idea of natural selection proposed that the ancient questions of political thought had been resolved by this breakthrough in zoology. When Hitler was young, an interpretation of Darwin in which competition was identified as a social good influenced all major forms of politics.

For Herbert Spencer, the British defender of capitalism, a market was like an ecosphere where the strongest and best survived. The utility brought by unhindered competition justified its immediate evils. The opponents of capitalism, the socialists of the Second International, also embraced biological analogies. They came to see the class struggle as “scientific,” and man as one animal among many, instead of a specially creative being with a specifically human essence. Karl Kautsky, the…

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Copyright © 2015 by Timothy Snyder