The history of exploration across nations and across time is not one where nations said, 'Let's explore because it's fun.' It was, 'Let's explore so that we can claim lands for our country, so that we can open up new trade routes; let's explore so we can become more powerful.'

Wanting to do one thing can require that you take on other interests.

It's part of our pop culture to give animals human personalities and talents.

You can deceive yourself into thinking that America is a technological leader, but if you don't see what anyone else is doing you have no accurate assessment - you can't make an accurate assessment of where you fit and why. I consider our moving frontier in space as the anecdote to that downward trend.

I remain fearless of airplanes after 9/11. But during a trip to Los Angeles on a Boeing 767, I couldn't keep my mind from drifting: What's the largest piece of this airplane that could crash into the World Trade Center, explode out the other side, and survive intact? The landing gear? My computer battery? My belt buckle? My wedding ring?

Thomas Jefferson basically secularized Jesus.

I was raised Catholic. But if someone says I was raised in some religion, that's insufficient information to actually know what was going on. The real question is Was the religion in the household? The answer is no. Important decisions in the household were executed rationally and secularly. So as a result, the foundations of my reasoning derive not from religion but from the rational analysis of circumstances.