释义：随随便便交一些不好的朋友，还不如整天读书更好。

数学不仅仅是关于数字、方程、计算或算法：它是关于理解的。

动物福利不仅仅是伦理问题——它是好的科学和好的商业。

The best leaders don't just manage; they inspire people to see possibilities where others see obstacles.

The poor are not irrational; they are just as rational as anyone else, but they operate under very different constraints.

心理过程是在生存斗争中的手段。