In science, if you don't do it, somebody else will. Whereas in art, if Beethoven didn't compose the 'Ninth Symphony,' no one else before or after is going to compose the 'Ninth Symphony' that he composed; no one else is going to paint 'Starry Night' by van Gogh.

The universe for me was other planets and other star systems and other galaxies. I enjoyed tracking it, but it had no specific influence on my ambitions for that reason. It wasn't really far enough away from Earth to matter to me.

Kids are never the problem. They are born scientists. The problem is always the adults. They beat the curiosity out of kids. They outnumber kids. They vote. They wield resources. That's why my public focus is primarily adults.

The number of people in the world engaged in this search for catastrophic impactors totals one or two dozen. How long into the future are you willing to protect Homo sapiens on Earth? Before you answer that question, take a detour to Arizona's Meteor Crater during your next vacation.

Computers have proved to be formidable chess players. In fact, they've beaten our top human chess champions.

While I'm a big fan of science fiction, especially as rendered in expensive Hollywood blockbusters, it's the real universe that calls to me. To fall into a black hole, that is more amazing than anything I've ever read in a science-fiction story.

I know of no time in human history where ignorance was better than knowledge.