出自《海国图志序》。善于学习外国的长处，就能够征服外国;不善于学习外国的长处就会被外国所征服。

代数分析很快让我们忘记了研究的主要对象，将注意力集中在抽象的组合上，直到最后我们才回到最初的目标。

History is not just the story of the past, but a mirror to the present and a window to the future.

"The truth is rarely pure and never simple."

I think if you do something and it turns out pretty good, then you should go do something else wonderful, not dwell on it for too long. Just figure out what's next.

"To write is to breathe, to live, to exist in the fullest sense."