Even if you have a brain predisposed to liberalism, you might end up with some conservative friends or find inspiring conservative role models who could be very influential on you, and that could send you down a different track in life.

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.

Reciprocity is a deep instinct; it is the basic currency of social life.

Sports is to war as pornography is to sex. We get to exercise some ancient, ancient drives.

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.

Suppose you read about a pill that you could take once a day to reduce anxiety and increase your contentment. Would you take it? Suppose further that the pill has a great variety of side effects, all of them good: increased self-esteem, empathy, and trust; it even improves memory. Suppose, finally, that the pill is all natural and costs nothing. Now would you take it? The pill exists. It is meditation.

I think the greatest work in social psychology from the 1950s and '60s is enormously important. I wish every high school kid could take a course in social psychology. I think we're making enormous strides in understanding the brain. These aren't yet giving us great insights, but I feel like we're on the verge of it. In five or ten years this basically searching the brain is really going to change things.