Abstract: Sidgwick thought that utilitarianism and egoism were rationally required, and left the dilemma of dualism of practical reason. In order to resolve dualism of practical reason, Parfit criticizes egoism from the point of temporal neutrality and personal identity, but some difficulties that face his criticism. The key for us to resolve dualism of practical reason is to construct the just social system and harmonize individual interest and universal interest, but not to illustrate that egoism is fully wrong.

Key words: dualism of practical reason, temporal neutrality, personal identity

摘要： 西季威克认为功利主义与利己主义是同样合理的,留下了实践理性二重性的难题。帕菲特分别从时间中立性与人格同一性两个角度对利己主义展开批判,力图消除实践理性二重性,但帕菲特的批判却面临着一些困难。文章认为,解决实践理性二重性的关键不是要证明利己主义是完全错误的,而是要创建正义的社会制度、辩证地处理好个人利益与普遍利益的关系。

关键词: 实践理性二重性, 时间中立性, 人格同一性