Joseph Henrich

might be part of the reason why humans are able to cooperate so much compared to other species.

And so we're thinking about that.

And then I heard about this experiment called the ultimatum game.

And the ultimatum game is a simple bargaining game from economics.

in which two players are allotted a sum of money and the first player can offer a portion of this money to the second player.

The second player can either accept or reject.

If they accept, both players get the amounts that were allocated, or if they reject, then both players get zero.

So for example, if the first player offers $10 out of the hundred to the second player and the second player accepts, they get 10 and the first player gets 90.

If they reject, both players get zero.

So when this had been done by economists in places like the U.S.

and Zurich and elsewhere, they had found that most people offer 50-50 and that low offers are frequently rejected.

That sort of fit my intuitions.

So I thought that I could perform this experiment among the Machiganga and they would show similar results.

seemed intuitive, and that then this would be an interesting piece of the puzzle in trying to explain human cooperation.

But what I found was that they didn't feel inclined to reject at all, and people gave pretty low offers.

So on average, people gave only 25% of the stake instead of 50%, and lots of people gave 15%.

So this led to a big project, and we did this experiment in many different places, and we found a great deal of global variation.

Well, I think it relates to a larger story that you and I discussed with the spread of the clocks.

It has to do with market integration.

And so what we found across these communities is that the more market-integrated communities seem to have norms about fair dealing with anonymous others, with impersonal