Not So Selfish After All

Imagine you are given ten dollars to split with a stranger. You can offer them any amount you like. If they accept, you both keep your shares, but if they reject the offer, neither of you gets anything. A purely self-interested stranger, according to classical economics, should accept any positive offer—even one dollar—because one dollar is better than nothing. When researchers ran this experiment across dozens of countries, they found that offers below thirty percent of the total were rejected roughly half the time: people would rather walk away with nothing than accept an outcome they perceived as unfair. In some communities, rejection rates were even higher. This experiment, called the ultimatum game, has been run so many times and reproduced so reliably that its basic finding is no longer seriously contested. People care about fairness, punish violations of it at cost to themselves, and do so even with strangers they will never see again. This directly contradicts the assumptions…