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.

The world is full of broken people.

不管先人是多么富贵，一个败家子就足以损坏门楣。

Innovation is not just about creating something new; it's about improving what already exists.

NP完全性的概念为理解计算问题的复杂性提供了一个强大的工具。

石油的真正价值在于它改变经济和社会的能力。