Disentangling material, social, and cognitive determinants of human behavior and beliefs

In social interactions, human decision-making, attitudes, and beliefs about others coevolve. Their dynamics are affected by cost-benefit considerations, cognitive processes (such as cognitive dissonance, social projecting, and logic constraints), and social influences by peers (via descriptive and injunctive social norms) and by authorities. This study disentangles these factors using an integrative mathematical model and a 35-day online behavioral experiment based on a Common Pool Resources game with or without authority messaging promoting a group-beneficial extraction level. We directly estimate the weights of different factors in decision-making and belief dynamics. Personal norms and conformity with expected peers’ actions have the largest impact on decisions, while material benefits and normative expectations have smaller effects. Prosocial individuals place higher weight on personal norms; antisocial types are more influenced by conformity. Messaging decreases the weight of personal norms while increasing the weight of conformity, and markedly shifts personal norms and normative expectations. Both cognitive and social factors are important in belief dynamics. Substantial between-individual variation shapes group behavior, while gender differences are small. Understanding social behavior requires modeling the dynamics of personal beliefs and beliefs about others, with cognitive, social, and material factors all playing key roles. The results inform predictions of social processes under shocks and the design of policy interventions to change behavior.