# Human Nature the World Over? Not So Fast

Let’s say you’re playing a game with three other people, with each player having 20 poker chips. Each of you decides how many chips to keep for yourself and how many to pool. You get 0.4 chip for each chip tossed into the common fund, even if you yourself kicked in zero.

So if two players donate five chips each to the pool, for a total of 10, then you and the other free-loader have 24 chips each—your original 20 + (0.4 times 10 chips, or 4)—while the generous pair have 19: 20 minus the 5 they contributed plus (0.4 times the 10 in the pool, or 4). It looks like free-loading is the smart strategy. Except for one thing: if everyone kicked in all 20 of their chips, so the pool had 80, then everyone would do better, getting 0.4 times 80 = 32 chips.

When scientists have run this “public goods” game, they have found that, especially after a few rounds, volunteers tend to kick in quite a lot of chips. That’s particularly so if contributors can punish free-loaders. From this, scientists spun tales of a universal human impulse to punish defectors, to cooperate, and the like.

Not so fast. To their credit, scientists in England and Switzerland have now run the experiment in 16 different cities, from Bonn and Zurich to Muscat (Oman), Minsk (Belarus), Seoul and Riyadh. Suddenly, human "universals" didn’t look so universal.

Over 10 rounds of the game, 1,120 middle-class college students in Boston and Copenhagen contributed about 18 chips; those in Athens, Riyadh and Istanbul, only six. The most-cooperative participants, who kicked in 90 percent of their chips, contributed 3.1 times as much as the least-cooperative, who had an average contribution of 29 percent of their chips. Readers are invited to insert their own explanation here; extra points for resisting ethnic slurs.

Then the scientists added another layer to the game. Not only were freeloaders punished. Now they could meekly accept their punishment, or retaliate—by docking their punishers for, well, enforcing the social ideal of cooperating for the common good. The frequency of “revenge punishments,” which the scientists call “antisocial punishment of prosocial cooperators,” was all over the map and “widespread in many participant pools,” they write in tomorrow’s issue of the journal Science—but, crucially, not in societies where most of earlier work on altruistic punishment has been done and which served as the basis for conclusions about universal human nature. That undermines the claim that lack of revenge punishments--that is, accepting your punishment gracefully--is part of human nature.

Students in Boston and Copenhagen accepted their slap-down, rarely seeking revenge on their punishers, perhaps because they knew that free-loading was reprehensible. Those in Athens and Muscat had the highest level of revenge punishments, retaliating against the enforcers about six times as often as did students in Seoul, Bonn Nottingham and several other cities. Samarra, Minsk, Istanbul and Riyadh were in the middle.

Punishment did not always increase cooperation in subsequent rounds, as had been reported in studies of the public-goods game that used only American college students; sometimes, people responded to being punished by getting huffy and refusing to kick in chips to the pool.

Why the difference in people’s behavior? For one thing, the results correlate with measures of civic cooperation and the rule of law, the researchers found. In societies where cooperation is the norm and people trust law enforcement, revenge is rare. But where the ethic of cooperation with strangers has not taken hold and the rule of law is weak, revenge is more common. Apparently, social norms can shape this supposedly biological (did someone say genetic?) thing called human nature.

The game may seem silly, but it has important real-world analogues. Societies must cooperate when it comes to “hunting, voting, paying taxes, fighting corruption, contributing to public goods, teamwork, work morale, neighborhood watch, common pool resource management, recycling, tackling climate change, and so on,” the scientists write. Yet these are all instances in which free-loaders can reap the benefits of other people’s cooperation while enriching themselves—you know, the people who still drive gas-guzzlers while the rest of us are trying to reduce our carbon footprint, or who cheat on their taxes while the rest of us fork over our payments.

As the scientists note, “tax evasion, abuse of the welfare state, or dodging fares on public transport . . . can [all] be modeled as public goods problems. The stronger norms of civic cooperation are in a society, the more free riding might be viewed as unacceptable and the more it might be punished in consequence.”

There’s nothing wrong with seeking universal truths of the natural world—hey, it worked for Newton, who realized that the same force kept plants in orbit and pulled objects to the ground. But once social scientists got physics envy, they decided to look for human universals—of behavior, morality, attitudes, mate preferences and the like. Cultural anthropologists were apoplectic, pointing out the huge variety of human cultures and their attendant attitudes and all the rest. This study drives home the message that extrapolating from studies on western college students—the default group for so much of this research—to the rest of humanity might not be the smartest move.