Derek Parfit
（重定向自Parfit）
Derek Parfit (/ˈpɑːrfɪt/; born 11 December 1942) is a British philosopher who specialises in problems of personal identity, rationality, ethics, and the relations among them.
His 1984 book Reasons and Persons (described by Alan Ryan in The Sunday Times as "something close to a work of genius") has been very influential. His most recent book, On What Matters (2011), was widely circulated and discussed for many years before its publication.