教育是保护的基础——人们保护他们所理解的东西。

Robots should think like humans, not humans work like robots.

You are not the opinion of somebody who doesn’t know you or care about you.

有没曾阅读过的书，没有不可对人说的事。

I don’t run out of material. I run out of time.

动力学的方程在用变分法的语言表达时是完全的。