Since life on Earth is, so far, the only known example of life in the universe, our dilemma may simply be that we have no other examples to compare us with. If we did, then the life/non-life transition might look downright simple to us.

I want to create the airplane that flies in the rarified atmosphere of Mars. This is what galvanizes a generation to want to become scientists and engineers in the first place, not we need a scientist to develop a plane that's 20 percent more fuel-efficient than the one your parents flew.

Follow the evidence wherever it leads, and question everything.

There's a lot of memorization that goes on in school. You memorize vocabulary words and all these sorts of things.

I have a very high respect for professional comedians. What they do astonishes me. You have to be really smart and absorb everything, repackage it, bring it back to the person, and make them laugh at themselves. I can make people laugh during my talks because they didn't come to have me make them laugh. It's added value. So my job is way easier than that of a professional comic.

Only when creative people take ownership of cosmic discovery will society accept science as the cultural activity that it is.

The worst thing that ever happened to America was the 19th Amendment.