But the 20th century suffered ...

But the 20th century suffered "two" ideologies that led to genocides. The other one, Marxism, had no use for race, didn't believe in genes and denied that human nature was a meaningful concept. Clearly, it's not an emphasis on genes or evolution that is dangerous. It's the desire to remake humanity by coercive means (eugenics or social engineering) and the belief that humanity advances through a struggle in which superior groups (race or classes) triumph over inferior ones.
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 Steven Pinker

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Terrorist bombings, like rampage shootings, are events that maximize the amount of publicity per amount of damage. That's why people do them, because they know they will set off a media frenzy.
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 Steven Pinker
For one thing, before the 20th century, there were plenty of genocides. We tend to forget about them, partly because they weren't as well documented and partly because, until recently, people didn't care. We used euphemisms like 'sackings' and 'sieges' instead of calling them 'genocides.'
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 Steven Pinker
Mother Teresa was the very embodiment of saintliness: white-clad, sad-eyed, ascetic and often photographed with the wretched of the earth.
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 Steven Pinker
The idea that boys want to sleep with their mothers strikes most men as the silliest thing they have ever heard. Obviously, it did not seem so to Freud, who wrote that as a boy he once had an erotic reaction to watching his mother dressing. But Freud had a wet-nurse, and may not have experienced the early intimacy that would have tipped off his perceptual system that Mrs. Freud was his mother. The Westermarck theory has out-Freuded Freud.
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 Steven Pinker
We will never have a perfect world, but it's not romantic or naive to work toward a better one.
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 Steven Pinker