No one is useless in this world who lightens the burdens of another.

Life is a play, and we must play our parts well.

Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.

When negotiating， don‘t aim for a bigger piece of the pie； aim to create a bigger pie.

不要批评你不理解的东西。