最危险的事情就是自以为知道自己在做什么。

Poor is the man whose pleasures depend on the permission of another.

I'm not interested in the nice and pretty. I'm interested in the intense and the emotional.

If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.

教师必须具有健康的体魄，农人的身手，科学的头脑，艺术的兴味，改革社会的精神。