"The truth is rarely pure and never simple."

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

Mathematics is the poetry of logical ideas.

When you solve a mathematical problem, you don't just get the answer - you understand why it's the answer.

读诗应当以心灵去感悟心灵，不能仅从字面意思去理解。