革命道德不是从天上掉下来的。它是在日常斗争中培养，在革命活动中锤炼的。

"There is a world of difference between the love we feel for a wild creature and the love we feel for a human being."

This is a group with many gifts. I'm sure one of your gifts is the gift of a smart and capable brain. I'm confident that's the case because admission is competitive and if there weren't some signs that you're clever， the dean of admission wouldn't have let you in.

目标是成为最好的，而不是击败别人。

我们都愿意为某种事业变得野蛮。好人与坏人的区别在于对事业的选择。

数学的进步是通过它能解决的问题数量来衡量的。