THE COUP DE GRASSO.(public outrage leads New York Stock Exchange Chaiman Richard Grasso to resign)

At the end of your typical Horatio Alger novel, the plucky hero, having risen from the streets, is allowed to bask in his good fortune. He's celebrated, not vilified, for the prosperity he has gained. So Dick Grasso, the former chairman of the New York Stock Exchange, a working-class kid from Queens who had made it into the city's upper echelons, could hardly have anticipated the public furor over his hundred-and-eighty-eight-million-dollar pay package--a sudden fit of populist outrage that, two weeks ago, forced him to resign. Americans love the idea of getting rich. What, then, made them rail against Dick Grasso's millions?

The answer might have something to do with the "ultimatum game," a well-known experiment in behavioral economics. The game is simple enough. Take two people. Give them a hundred dollars to split. One person (the proposer) decides, on his own, what the split should be (fifty-fifty, seventy-thirty, or whatever) and makes the other person a take-it-or-leave-it offer. If he accepts the deal, both players get their share of the money. If he rejects it, both players walk away empty-handed.

The rational thing for the second person to do is to accept the offer, whatever it is, since even one dollar is better than nothing. But in practice this rarely happens. Instead, lowball offers are almost always rejected. Apparently, people would rather throw away money than let someone else walk away with too much. Other experiments illustrate the same idea. Essentially, people are willing to pay to punish those they think are free-riding or acting unfairly, even when doing so brings them no material benefits. The economists Samuel Bowles and Herbert Gintis call this the principle of "strong reciprocity." Strong reciprocity works; it makes the whole system fairer. In the ultimatum game, for instance, the proposer usually ends up offering a relatively equitable split (say, sixty-forty) to insure that the other person accepts.

It so happened that, on the very day Grasso resigned, the primatologists Sarah F. Brosnan and Frans B. M. de Waal released a study showing that female brown capuchin monkeys seem to have a sense of fairness, too. Pairs of capuchins had been trained to give Brosnan pebbles in exchange for slices of cucumber. This idyllic monkey market economy was disrupted, though, when the scientists changed the pay scale, rewarding one monkey with a delicious grape and the other with the same measly old cucumber. Exposed to this injustice, the capuchins who were given cucumbers often refused to eat; forty per cent of the time, they stopped trading entirely. Things got worse when one monkey in each pair was given a grape for doing nothing at all. The other monkeys often responded by tossing away their pebbles; eighty per cent of the time, they stopped trading. The capuchins were willing to forfeit cheap food simply to express their displeasure at their partners' unearned riches.

The point was not--as some of the news coverage suggested--that capuchins are innate ...