When buying a garden hose， an extension cord， or a ladder， get one substantially longer than you think you need. It’ll be the right size.

"In the end, we are all stories. What matters is how we tell them."

数学的研究就像空气或重力——它无处不在，你看不到它，但你知道它在那里。

你不可能永远快乐，但你可以永远勇敢。