What set us apart from most or all of the other hominid species was our ultrasociality, our ability to be highly cooperative, even with strangers, people who are not at all related to us.

I think moral philosophy is speculation on how we ought to live together done by people who have very little clue how people work. So I think most moral philosophy is disconnected from the species that we happen to be. In fact, they like it that way. Many moral philosophers insist that morality grows out of our rationality, that it applies to any rational being anywhere in the universe, and that it is not based on contingent or coincidental facts about our evolution.

The mind is divided, like a rider on an elephant, and the rider’s job is to serve the elephant. The rider is our conscious reasoning-the stream of words and images of which we are fully aware. The elephant is the other 99 percent of mental processes-the ones that occur outside of awareness but that actually govern most of our behavior.

Individuals who could not form cooperative alliances, on average, died sooner and left fewer children. And so we are the descendants of the successful cooperators.

Intuitions come first, strategic reasoning second.

If you grow up in a WEIRD society, you become so well educated in the ethic of autonomy that you can detect oppression and inequality even where the apparent victims see nothing wrong.

Do people believe in human rights because such rights actually exist, like mathematical truths, sitting on a cosmic shelf next to the Pythagorean theorem just waiting to be discovered by Platonic reasoners? Or do people feel revulsion and sympathy when they read accounts of torture, and then invent a story about universal rights to help justify their feelings?