In the world of physics, we often find that the simplest questions are the hardest to answer.

The dangerous man is the one who has only one idea, because then he'll fight and die for it.

With a library you are free, not confined by temporary political climates. It is the most democratic of institutions because no one - but no one at all - can tell you what to read and when and how.

There is no short cut to achievement. Life requires thorough preparation.

The thought of death should usher us towards whatever happens to matter most to us; it should lend us the courage to pursue the way of life we value in our hearts.

应对不自由世界的唯一方法是变得如此绝对自由，以至于你的存在本身就是一种反叛。