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

The only thing necessary for the triumph of evil is for good men to do nothing.

The sun, with all those planets revolving around it and dependent on it, can still ripen a bunch of grapes as if it had nothing else in the universe to do.

有时候最难的事情和正确的事情是同一件事。