学习数学的最好方法就是做数学。

一个好的经济学家必须既是科学家，又是人文主义者。

True freedom is inner freedom.

学习是通过修改符号结构来提高性能的过程。

我们都受到过去幽灵的困扰，但由我们决定是让它们困扰我们还是引导我们。

"The past is never dead. It's not even past."

I know you've heard it a thousand times before. But it's true-hardwork pays off. If you want to be good, you have to practice, practice, practice.