It may be that you really care about the other guy, and very often that’s the case. Human beings’ notion of empathy is very strong. And that’s what altruism is. It’s wanting to help people at a cost to yourself — but also punish people at a cost to yourself when they’re behaving in an anti-social manner. And then the question is, how can human beings be this way? No other species is like this. And that’s where the biology comes in. You have to show that groups in which you have a strong reciprocator, an altruist, will do better than groups that don’t have altruism.

Is that how game theory fits in?

The main thing game theory does is provide a methodology for experiments. After that, you’ve got all the biology, genetics, sociology. But game theory pervades everything we do. There’s a whole theory on that called “behavioral game theory.”

Tell us about your recent findings on how altruism is transmitted.

We’re basically very hard-nosed mathematical behaviorists. We take the economic model of the rational actor and we put it through the hoops.

Sociologists have a concept called socialization, which means the internalization of norms, which is completely opposite from every other behavior. There’s no such thing in biology or economics or political science or anthropology.

It seems to me that the principle of socialization was one of the established behavioral universal principles in academic sociology. What we propose is that human beings have this capacity to be programmed. Humans are the only ones where humans can want things just because they were socialized to want them — want to be fair, want to share, want to help your group, want to be patriotic, want to be honest, want to be trustworthy, want to be cheerful — when they are costly to our selves. If you’re honest as a principle, that’s good for everybody else and it costs you. So being honest is part of strong reciprocity.

Where does this come from?

Within a complex society, the general approach to this is gene-culture co-evolution. In biology, you get genetic information. In sociology or anthropology, you get cultural information. But really, in human society, they go together. Genetic evolution leads to culture. In that culture, given strong reciprocity, you can be rewarded for being nice or for cooperating. So cultural evolution can lead to genetic evolution. Human beings become nicer and more reciprocal and more honest. So, you get this whole dialectic back-and-forth between cultural evolution and genetic evolution and the product is human beings.