闻贤而不举，殆；闻善而不索，殆；见能而不使，殆
解释：闻知有道德的人不予荐举，听说有善良的人不去寻求，见到有才能的人不予使用，那是很危险的。
写下那些不应该被遗忘的事情。
在计算中，不变量是短暂的。
The only way to understand another culture is to assume the frame of reference of that culture.
You can't please everyone, so don't try.
The best way to learn econometrics is by doing—working with real data and real problems.