Every book is a door that opens onto another world, and every reader is a traveler who steps through it.
谁是神智健全的人?我能把他治好。
我在历史中学到的唯一东西就是:大众从未从历史中汲取教训。(11月17日名言)
今天种下的每一棵树,都是对明天的承诺。
A mathematical truth is universal and eternal.