Social identity emergence in attitude interactions and the identity strengthening effects of cumulative attitude agreement

The social identity approach asserts that self-categorization is fluid and created anew in context. Despite this, research often conceptualizes identities as being based on static categories. In this article, we assess: how attitudes may be relevant attributes used to categorize the self and others, and therefore have the potential to foster social identification; how such categories/identities can be updated with new attitudinal information; and how attitudes have greater impact when socially expressed. Across three preregistered computer-mediated interactive experiments (N = 3087), involving attitudes relating to the Ukraine-Russia conflict of 2022, we find, identities can be updated with the introduction of new attitudes in interaction; cumulative attitude congruence strengthens identification; attitudinal interaction strengthens opinion-based group identification and activism intentions, and ingroups can strategically align their attitudes. We conclude that to fully understand identity formation, we must acknowledge the fluidity of self-categories and resultant identities, in line with the original specifications of the social identity approach.