The ultimate measure of a man is not where he stands in moments of comfort and convenience， but where he stands at times of challenge and controversy.

Every line we draw carries responsibility.

I have to say to myself that some birds aren't very close. Their feathers are just too bright. When they fly away, you know it's a sin to lock them up, and you'll be inspired by them. Still, the place you live in is that much more drab and empty that they're gone. I think I really miss my friends.

要快乐，我们不必太在意别人。

有时候，解决问题的最好方法就是完全避开它。

计算复杂性的美在于它能够揭示问题的固有难度，而不管用于解决这些问题的具体算法是什么。

Our greatest ability as humans is not to change the world, but to change ourselves.