在年老之后，你会发现自己的双手能解决很多难题。一只手用来帮助自己，另一只用来帮助别人。
As you grow older, you will discover that you have two hands, one for helping yourself, the other for helping others.
I don't believe in retirement. I believe in continuing to work as long as you're able.
Have a heart that never hardens, and a temper that never tires, and a touch that never hurts.
数学是模式的科学，而自然利用了每一种可能的模式。