Is our conscience nothing but “the inner voice that tells us that somebody might be looking,” as the jaundiced H.L. Mencken (1949) put it? Or did the 20th century American essayist overlook humanity’s penchant genuinely to care for others, including total strangers, and to act morally, even when nobody is looking? And if Adam Smith’s affirmation of humanity’s moral sentiments is more nearly correct than Mencken’s skepticism, how could this oddly cooperative animal, Homo sapiens, ever have come to be?
In the pages that follow we advance two propositions.
First, people cooperate not only for self-interested reasons but also because they are genuinely concerned about the well-being of others, try to uphold social norms, and value behaving ethically for its own sake. People punish those who exploit the cooperative behavior of others for the same reasons. Contributing to the success of a joint project for the benefit of one’s group,even at a personal cost, evokes feelings of satisfaction, pride,even elation.Failing to do so is often a source of shame or guilt.
Second, we came to have these “moral sentiments” because our ancestors lived in environments, both natural and socially constructed, in which groups of individuals who were predisposed to cooperate and uphold ethical norms tended to survive and expand relative to other groups, thereby allowing these prosocial motivations to proliferate. The first proposition concerns proximate motivations for prosocial behavior, the second addresses the distant evolutionary origins and ongoing perpetuation of these cooperative dispositions.
Cooperation was prominent among the suite of behaviors that marked the emergence of behaviorally modern humans in Africa.