理智是不朽的，其他一切都是有限的。
Reason is immortal， all else mortal.
The best way to ensure peace is to maintain a balance of power among the great powers.
Technological development should serve humans, not replace them.
In mathematics, you don't understand things. You just get used to them.
有时候最难的事和最正确的事是同一件事
原文英文：The most merciful thing in the world， I think， is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity， and it was not meant that we should voyage far.