Abstract
Human social life is rife with uncertainty. In any given encounter, one can wonder whether cooperation will generate future benefits. Many people appear to resolve this dilemma by initially cooperating, perhaps because (a) encounters in everyday life often have future consequences, and (b) the costs of alienating oneself from long-term social partners often outweighed the short-term benefits of acting selfishly over our evolutionary history. However, because cooperating with other people does not always advance self-interest, people might also learn to withhold cooperation in certain situations. Here, we review evidence for two ideas: that people (a) initially cooperate or not depending on the incentives that are typically available in their daily lives and (b) also learn through experience to adjust their cooperation on the basis of the incentives of unfamiliar situations. We compare these claims with the widespread view that anonymously helping strangers in laboratory settings is motivated by altruistic desires. We conclude that the evidence is more consistent with the idea that people stop cooperating in unfamiliar situations because they learn that it does not help them, either financially or through social approval.
