The true nobility is in being superior to your previous self.
In the world of physics, we often find that the simplest questions are the hardest to answer.
The proof of a system's value is its existence.
衡量一个文明的标准是它如何对待其作家。
In mathematics, you don't understand things. You just get used to them.
过去从未死去，它甚至不是过去。
A legal system is a system of rules which are valid according to the system's own criteria of validity.