市场经济的本质是自由竞争，而竞争的本质是自由进入。

The truth is, we are all capable of terrible things. But we are also capable of great kindness.

"The past is a puzzle, and the historian is the person who tries to put the pieces together."

我们教授一门学科不是为了培养关于该学科的小型活图书馆，而是让学生自己学会数学思考。

人生苦短，不能不追随梦想。