But it is the same with man as with the tree. The more he seeks to rise into the height and light, the more vigorously do his roots struggle earthword, downword, into the dark, the deep - into evil.

A good mathematician is someone who can see analogies between theorems; a great mathematician is someone who can see analogies between analogies.

你能创造的最有价值的东西就是错误——你无法从完美中学到任何东西。

数学家是将咖啡转化为定理的装置。