保持虚心才能了解实情，保持冷静才能判断行动是否正确
Parents wonder why the streams are bitter, when they themselves have poisoned the fountain.
Every project must respond to its context, not just physically but socially and historically.
The question is, are we happy to suppose that our grandchildren may never be able to see an elephant except in a picture book?
The best way to learn is by doing, not just by listening or reading.