"I was trying," he said, "to put the history of mankind in one sentence." Later he said, "I am still trying to do it, but now I want to put it all on the head of a pin."

VOA: special.2010.01.03

I'm really liberal, but this disturbs me because I am looking at you, I'm trying to see from your reaction how much of my lecture you are following, and then it's very distracting when people are talking.

很无所谓的,但是我很不喜欢有人说话,因为我正看着你,我要根据你的反应来判断,我的课你听懂了多少,但是如果有人说话的话,就会让大家分神

耶鲁公开课 - 基础物理课程节选