Some of the most fundamental questions concerning our evolutionary origins, our social relations, and the organization of society are centred around issues of altruism and selfishness. Experimental evidence indicates that human altruism is a powerful force and is unique in the animal world....

In experiments, animals often prefer smaller, immediate rewards over larger rewards that are deferred — thus failing to maximize their total gain. Many people exhibit similar behaviour.

Human cooperation is an evolutionary puzzle. Unlike other creatures, people frequently cooperate with genetically unrelated strangers, often in large groups, with people they will never meet again, and when reputation gains are small or absent. These patterns of cooperation cannot be explained...

This paper provides strong evidence challenging the self-interest assumption that dominates the behavioral sciences and much evolutionary thinking. The evidence indicates that many people have a tendency to voluntarily cooperate, if treated fairly, and to punish non-cooperators. We call this...

We examine experimentally how Chief Executive Officers (CEOs) respond to incentives and how they provide incentives in situations requiring trust and trustworthiness. As a control we compare the behavior of CEOs with the behavior of students. We find that CEOs are considerably more trusting and...

Do employers and workers underbid prevailing wages if there is unemployment? Do employers take advantage of workers’ underbidding by lowering wages? We hypothesize that under conditions of incomplete labor contracts wage levels may positively affect workers’ propensity to cooperate. This, in...

The existence of social norms is one of the big unsolved problems in social cognitive science. Although no other concept is invoked more frequently in the social sciences, we still know little about how social norms are formed, the forces determining their content, and the cognitive and...