People perceive that if their memories and moral beliefs changed, they would change. We investigated why individuals respond this way. In Study 1, participants judged that identity would change more after changes to memories and widely shared moral beliefs (e.g., about murder) versus preferences and controversial moral beliefs (e.g., about abortion). The extent to which participants judged that changes would affect their relationships predicted identity change (Study 2) and mediated the relationship between type of moral belief and perceived identity change (Study 3). We discuss the role that social relationships play in judgments of identity and highlight implications for psychology and philosophy.