Combinatorics is the art of counting without counting.
组合数学是不用计数的计数艺术。
It’s not what we do once in a while that shapes our lives, but what we do consistently.
毁灭自己的错误胜过毁灭他人的错误。
It was like when you make a move in chess and just as you take your finger off the piece, you see the mistake you’ve made, and there’s this panic because you don’t know yet the scale of disaster you’ve left yourself open to.
知识就是力量。