I have already carried out my duty. I have proved the Poincaré conjecture and I have nothing more to do in mathematics.

I'm not afraid to say what I feel, and I'm not afraid to be who I am.

There's only one corner of the universe you can be certain of improving，and that's your own self.

天下的一切事物不可以没有标准，做人要有做人的标准，即原则;做事要有做事的标准，即规则;治国要有治国的标准，即法则。不遵循一定的标准而能成事者，自古以来是没有的。

I’ve learned that you have to be strong enough to stand alone, smart enough to know when you need help, and brave enough to ask for it.

【释义】快乐不在于外在环境，而在于自己的内心。

存在总是某种存在者的存在。

"Every book has a soul. The soul of the person who wrote it and of those who read it and dream about it."