什么也不做是世上最难的事情，最困难并且最智慧。

Well, the first rule is that you can’t really know anything if you just remember isolated facts and try and bang ’em back. If the facts don’t hang together on a latticework of theory, you don’t have them in a usable form.

【大意】说话一定要讲信用，约定了就一定要做到，这是天下的高尚行为。