In accounts of men in battle, there is an incredible adrenaline rush from group-versus-group conflict. The fervor and passion of partisans is clearly rewarding; and if it's rewarding, it involves dopamine; and if it involves dopamine, then it is potentially addictive.

Let me say it diplomatically: Most religions are tribal to some degree.

I began graduate school in the late 1980s, and my goal was to understand how morality varied across cultures and nations. I did some research comparing moral judgment in India and the U.S.A.

[W]hen a group of people make something sacred, the members of the cult lose the ability to think clearly about it. Morality binds and blinds.

We scientists have way too much a tendency to simplify problems. I guess it actually comes to us naturally. Take the simplest unit, separate out all the confusing, external factors. Study it. Make sure you understand it. And in psychology that means the person studying the individual. But if you want to study our social nature, if you want to study processes that will lead to war and peace, you don't learn all that much by looking at the single individual. A lot of the important things are emergent facts about us, things that you can only see when you get a lot of us interacting.

Love and work are to people what water and sunshine are to plants.

But the most important lesson I have learned in my twenty years or research on morality is that nearly all people are morally motivated. Selfishness is a powerful force, particularly in the decisions of individuals, but whenever groups of people come together to make a sustained effort to change the world, you can bet that they are pursuing a vision of virtue, justice, or sacredness.