没有什么是确定的,也没有什么是不可能的。
定理是永恒的;它们的证明是短暂的。
We must dare to dream, dare to practice, dare to fail, and dare to succeed.
知识是人类的最高财富,而分享知识则是最高的慷慨。
It is not the voice that commands the story; it is the ear.