The most important thing in mathematics is to ask the right questions.

长期来看，只有真正创造价值的人才能生存。

Invert, always invert: Turn a situation or problem upside down. Look at it backward.

Separate the processes of creation from improving. You can’t write and edit， or sculpt and polish， or make and analyze at the same time. If you do， the editor stops the creator. While you invent， don’t select. While you sketch， don’t inspect. While you write the first draft， don’t reflect. At the start， the creator mind must be unleashed from judgement.

——临终时对孔祥熙说，1925年3月