每个人都重要，否则没有人重要。

历史不仅仅是关于过去；它是关于我们如何理解现在并塑造未来。

The difference between a policy and a crusade is that a policy is judged by its results, while a crusade is judged by how good it makes its crusaders feel.

学习数学的唯一方法就是做数学。