On What Matters is a major work in moral philosophy. It is the long-awaited follow-up to Derek Parfit's 1984 book Reasons and Persons, one of the landmarks of twentieth-century philosophy. Parfit now presents a powerful new treatment of reasons, rationality, and normativity, and a critical examination of three systematic moral theories - Kant's ethics, contractualism, and consequentialism - leading to his own ground-breaking synthetic conclusion. Along the way he discusses a wide range of moral issues, such as the significance of consent, treating people as a means rather than an end, and free will and responsibility. On What Matters is already the most-discussed work in moral philosophy: its publication is likely to establish it as a modern classic which everyone working on moral philosophy will have to read, and which many others will turn to for stimulation and illumination.

德里克·帕菲特（DerekParfit），牛津大学万灵学院高级研究员，纽约大学、哈佛大学、罗格斯大学客座教授，英国国家学术院、美国人文与科学院成员。他的另一部著作《理与人》（Reasons and Persons）是近几十年最有影响力的哲学著作之一。

阮航，男，湖北黄陂人，1971年10月生。涨江大学建筑学专业本科，中南财经政法大学伦理学硕士、博士，现为湖北大学哲学学院副教授，湖北大学高等人文研究院文化发展报告部主任。公开发表论文30余篇，专著1部，译著2部。主要研究方向：伦理学理论、儒家伦理、政治哲学。

葛四友，哲学博士，华东师范大学哲学系教授，主要研究领域为规范伦理学与近现代英美政治哲学，当前主要的研究兴趣在于重建一种新的后果主义分配正义理论，同时发展新的后果主义且为之作辩，著有《正义与运气》，译有《运气均等主义》（编译）、《合理性的本质》（合译）和《公共领域中的伦理学》（主译）。