The key to comedy is timing, and the key to timing is patience.

You don't learn to walk by following rules. You learn by doing, and by falling over.

The real difficulty lies not in devising new ideas, but in escaping from the old ones.

Education is the most powerful weapon which you can use to change the world.

一个人若不能治理自己，便不能治理家庭；若不能治理家庭，便不能治理城市；若不能治理城市，便不能治理国家。

Chemistry is the art of building bridges between the microscopic and the macroscopic.