老年人相信每一件事物;中年人猜疑每一件事物;青年人什么都懂。
Darkness cannot drive out darkness: only light can do that. Hate cannot drive out hate: only love can do that.
The joy of mathematics is in the journey, not just the destination.
如果你仔细观察,平凡的事物也会变得非凡。
自由民主在世界范围内的传播并非不可避免,但它是历史进程中最可能的结果。