对中国国民党同志共勉，1920年1月1日
"A good book is an event in my life."
学识不够渊博的人们，就无法能够得到其中的要领。志向如果不够坚定，这样就不能够努力践行。
Technology innovation is the key to solving the trilemma of energy security, environmental protection and economic development.
当父母为孩子做太多时，孩子就不会为自己做太多。
The truth is that parents are not really interested in justice. They just want quiet.
The power of mathematics comes from its ability to abstract and generalize, turning specific problems into universal truths.