Learning to Cooperate: How First Impressions Shape Perceptions of Social Norms

People’s decisions about whether or not to cooperate are influenced by social norms—i.e., what they believe others are doing. In novel situations, people may infer social norms by observing exemplars. Here, we investigate how first impressions shape the inference of social norms. We hypothesized that, because people tend to anchor on early-encountered information, their perceptions of social norms will be most strongly influenced by the first exemplar they observe. Participants played a game in which they observed one player acting generously and another selfishly, or vice versa. Then they made a decision themselves. Results showed that those who first observed the generous exemplar believed that players in the game were more generous overall, and also acted more generously. These results highlight the power of first impressions to shape people’s perceptions of what behavior is acceptable—a finding with important implications for maintaining cooperative organizational cultures.