The best investment we can make is in the health of future generations.

教学的全部艺术，不过是唤醒年轻人天生的好奇心，以便日后满足它。

史记

To live is the rarest thing in the world. Most people exist, that is all.

The secret of joy in work is contained in one word – excellence. To know how to do something well is to enjoy it.

自动控制的根本问题是在存在干扰的情况下维持期望状态。