经济理论提供工具，但现实世界的测试会完善它们。

婴儿不是需要塑造的物品，而是需要展开的人。

教育的回报比大多数人意识到的要高。

The defining characteristic of pessimists is that they tend to believe bad events will last a long time, will undermine everything they do, and are their own fault.

诚信采矿意味着为子孙后代留下积极的遗产。