If you can’t tell what you desperately need， it’s probably sleep.

The greatest obstacle to being heroic is the doubt whether one may not be going to prove one's self a fool; the truest heroism is to resist the doubt, and the profoundest wisdom to know when it ought to be resisted, and when it be obeyed.

Global challenges require global collaboration.

The only true wisdom is in knowing you know nothing.

我不是说唱歌手，我是一个传奇。