When students cheat on exams, it's because our school system values grades more than students value learning.

The world, I think, has too many late-night talk shows.

There are countless space activities that would be no less exciting than the moon missions were, I have no doubt. The search for life on Mars, for example.

They [scientists of centuries past] call on God only from the lonely and precarious edge of incomprehension. Where they feel certain about their explanations, however, God gets hardly a mention.

I love the future we might invent for ourselves that I have not yet dreamt of.

In whatever you choose to do, do it because it's hard, not because it's easy. Math and physics and astrophysics are hard. For every hard thing you accomplish, fewer other people are out there doing the same thing as you. That's what doing something hard means. And in the limit of this, everyone beats a path to your door because you're the only one around who understands the impossible concept or who solves the unsolvable problem.

Aliens might be surprised to learn that in a cosmos with limitless starlight, humans kill for energy sources buried in the sand