Life is made up of sobs, sniffles, and smiles, with sniffles predominating.

变化是所有存在的基本过程。

Generally speaking, envy, resentment, and self-pity are disastrous modes of thoughts.Self-pity gets fairly close to paranoia, and paranoia is one of the very hardest things to reverse.

这不是一个非常芬芳的世界，但这是你生活的世界。

优秀的数学家应该既严谨又富有想象力。