Evolutionary foundations of social identity

Social identity theory provides a rich description of how humans relate to various kinds of social groups, but no substantive account of why human psychology evolved to be so group-minded in the first place. We propose that the evolutionarily original form of social identity was one's moral identity as a cooperative group member. For ancient humans, survival depended on being an assimilated member of a cultural group, which, in turn, competed against other groups. In this context, humans evolved skills and motivations for engaging in the collective agency of a cultural group, especially the self-reflective capacity to adopt a social identity (i.e. to construe oneself as a member of a ‘we’) and the concomitant self-regulatory motivation to maintain a positive social identity (i.e. to strive for ‘I’, the individual, to meet the standards that ‘we’ uphold). In this evolutionary proposal, behavioural effects of group identity, inferences of common knowledge and moral emotions are all manifestations of the function of social identity as a self-regulatory system for maintaining one's good standing as a cooperative group member. This article is part of the discussion meeting issue ‘From being to identity: analysis and synthesis of the self’.