生活不是等待风暴过去，而是学会在雨中跳舞。
The truth is rarely pure and never simple.
The most significant threat to liberal democracy today is not from the outside, but from within.
Mathematics is the most beautiful and most powerful creation of the human spirit.
Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.
数学不是关于数字、方程、计算或算法的：它是关于理解的。