Why we are nice to strangers

Latest Mind and Matter column from the Wall Street Journal:

Evolutionists long ago abandoned the idea that natural selection can promote only selfish behavior. In the right circumstances, animals-including human beings-evolve the instinct to be nice (or acquire habits of niceness through cultural evolution). This happens within families but also within groups, where social solidarity promotes the success of the group at the expense of other groups.

David Sloan Wilson, an evolutionary biologist who used his home town of Binghamton, N.Y., as a laboratory for his new book "The Neighborhood Project," is a champion of this kind of "group selection." He finds that "the most prosocial kids in Binghamton also received the most social support." Like many statements in evolutionary psychology, this one is both obvious and profound, telling us what we knew anyway but also shocking us into realizing that our folk knowledge gives a particular insight into human nature.

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John S. Dykes

Dr. Wilson finds that, socially, humans give what they get and get what they give. In Binghamton, people who are "bathed in social support" from family, neighborhood, school, religion and extracurricular activities tend to score highly on questions about how much they help other people. They are also more likely to venture to trust others in experimental games.

There is an obvious policy implication: Give social support and you will create a better neighborhood. Dr. Wilson's painstaking care in documenting the connection in real communities on the ground is worth any amount of assertion from politicians that this is the right thing to do. And he is right to see it as an instance of evolutionary "path dependence" (each step made possible by the previous one): "The idea that any species can be studied without reference to evolution is patently absurd."

Like many other evolutionary biologists, Wilson sees the issue of cooperation in social, rather than economic, terms-that is, as a matter of generosity or altruism rather than of trade. Others in the field discuss ideas like "strong reciprocity": the notion that successful societies implicitly agree to punish selfish behavior, thus enforcing norms of niceness.

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John S. Dykes

For me, this creates a problem, and Dr. Wilson unwittingly emphasizes it: The more evolution encourages niceness within groups, the more it produces nastiness between them. Dr. Wilson thinks "the future is bleak if we don't turn our groups into organisms," by which he means entities that emulate the team behavior of cells in a body. But surely the future is bleak if we do turn groups into such organisms. Consider gangs, armies, sports fans and companies, which have taken this advice-and, as a result, fight each other.

As Adam Smith pointed out, kindness works among friends and relatives, but for cooperation among strangers, human beings use a wholly different mechanism: a division of labor that encourages people to engage in mutual service. Plenty of other animals (from chimpanzees to ants) show cooperation within groups and proportionate antagonism between them, whereas none has exchange and specialization between strangers. History shows that it is trade that dissolves hostility between groups.

A few years ago, Joe Henrich of the University of British Columbia and his colleagues did a series of experiments in small-scale societies in the Amazon, New Guinea and Africa. They asked people to play the "ultimatum game," in which a player must decide how much of a windfall he needs to share with another player to prevent the other player from exercising his right to veto the whole deal. The more the small-scale society is enmeshed in modern commerce, the more generous the offers people make. This may shock those who believe in Rousseau's idea of the "noble savage," but not those who believe in the virtues of what Montesquieu called "sweet commerce."

Dr. Wilson does not discuss commerce as a source of cooperation in Binghamton, and he dislikes economics. So he misses the point that, though human beings do kind things unrewarded for their neighbors, for reward they also do kind things for strangers: They hand more cash to merchants than they do to beggars.