This paper presents a novel experiment on group conflict. Subjects are divided into groups according to preferences on paintings, and subjects are divided into groups according to self-declared political affiliations and leanings. Using a unique within subject design, we find twenty percent of subjects destroy social welfare – at personal cost – when facing a subject outside their group. This e...

Social identities are associated with normative standards for thought and action, profoundly influencing the behavioral choices of individual group members. These social norms provide frameworks for identifying the most appropriate actions in any situation. Given the increasing complexity of the social world, however, individuals are more and more likely to identify strongly with multiple socia...

Cognitive control resolves conflicts between appropriate and inappropriate response tendencies. Is this achieved by a unitary all-purpose conflict control system, or do independent subsystems deal with different aspects of conflicting information? In a fully factorial hybrid prime-Simon task, participants responded to the identity of targets displayed at different nominally irrelevant screen lo...