优秀的数学家应该既严谨又富有想象力。
A good mathematician should be both rigorous and imaginative.
Your time is limited, so don't waste it living someone else's life.
Success is not final, failure is not fatal: It is the courage to continue that counts.
The only thing that is truly valuable is the time you spend with people you love.
I don't write for the reader, I write against the reader.