"My grandfather said people who can learn, learn morality the way they learn everything else, by building on history. He also said that some people cannot learn from history, so they cannot change. For them, there’s only one book or tradition or whatever it’s called in their religion, and in that book God is eternal and whatever the book says God commanded two or three or four thousand years ago, God still commands today. That may be kill homosexuals or kill nonbelievers. It may say enslave your enemies. It may say mutilate or sequester women, or sell your ten-year-old daughter for somebody’s third wife."