In everyday life we assume substantial behavioural reliability in others, and on the basis of it wetalk of people as acting “in character” and “out of character”. This common assumption seemsintuitively well founded. But recent experiments in social psychology have generatedphilosophical controversy around it. In the context of this debate, John Doris challengesAristotle’s well known and influential view that people’s behavioural reliability with respect toacting virtuously is underpinned by character traits, understood as settled and integrateddispositions of the agent to have appropriate judgment and appropriate feelings toward what sheis called upon to do in a given situation. In this paper I will take John Doris’ challenge at facevalue,...