The most important thing is to keep your mind active.

一个问题如果在计算机上可以快速解决，那么它属于P类问题；如果一个解可以快速验证，那么它属于NP类问题。

Generally speaking， the errors in religion are dangerous； those in philosophy only ridiculous.

每一粒播种的种子都是对我们想要生活的世界的一次投票。

Anarchy is the permissive cause of war; it creates an environment in which states have to rely on self-help to ensure their survival.