The natural effort of every individual to better his own condition， when suffered to exert itself with freedom and security， is so powerful a principle that it is alone， and without any assistance， not only capable of carrying on the society to wealth and prosperity but of surmounting a hundred impertinent obstructions with which the folly of human laws too often encumbers its operations.

追求数学知识是一段永无止境的旅程。

It is in the thirties that we want friends. In the forties we know they won't save us any more than love did.

语言是我们改变世界最强大的武器。

做出伟大工作的唯一方法就是热爱你所做的事。

做这件事的唯一方法就是去做。

"The only way to deal with an unfree world is to become so absolutely free that your very existence is an act of rebellion."