There is no easy answer to that question.

VOA: special.2009.11.22

There is obviously no magic solution to this question but the best answer I know of is Socrates.

这个问题,没有神奇的解答,但我认为最佳的答案是苏格拉底。

耶鲁公开课 - 政治哲学导论课程节选

Well, maybe the answer is there's no particular time at all when I killed him But for all that, it's true that I killed him ? What makes it true that I killed him?

也许答案是,我什么时候杀死他根本没有确切的时间,尽管如此，我杀死他是真的,为什么我杀死他是真的？

耶鲁公开课 - 死亡课程节选