数学不是关于数字、方程、计算或算法的:它是关于理解的。
Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.
The only thing that counts is what cannot be explained.
真正的监狱不是由围墙构成,而是由沉默的舌头和被审查的思想构成。
The imagination is a muscle. If it is not exercised, it atrophies.