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.
爱既不善良也不诚实,并且不会以任何可靠的方式促进幸福。
Train people well enough so they can leave, treat them well enough so they don't want to.