数学不仅仅是关于数字、方程、计算或算法：它是关于理解的。
Mathematics is not just about numbers, equations, computations, or algorithms: it is about understanding.
If you want to be happy, be.
我宁愿在尝试中失败，也不愿在保守中成功。
The act of writing is an act of optimism. You would not take the trouble to do it if you felt it didn't matter.
The art of teaching consists in large part of the ability to awaken the natural curiosity of young minds and to satisfy it with the nourishment of knowledge.
什么是言论自由？没有冒犯的自由，言论自由就不复存在。