The study is centred on the problem of personal identity. The discussion, particularly in contemporary Anglo-Saxon philosophy, is dominated by reductionist approaches which take psychological continuity as a criterion for identity. The author places these theories in a comprehensive historical and systematic context. He fills an important gap in the discussion. The criteria problem is linked with a study into the conditions for constituting personality. It counters rash simplifications by showing that the contextual dependence of the concept of person requires a plurality of specific identity criteria.