Exploration is what you do when you don't know what you're doing. That's what scientists do every day. If a scientist already knew what they were doing, they wouldn't be discovering anything, because they already knew what they were doing.

We spend the first year of a child's life teaching it to walk and talk and the rest of its life to shut up and sit down. There's something wrong there.

We live in a world where not everyone has the urge to help others... It is OK to encourage others to pull themselves up by the bootstraps, but if you do, just remember that some people have no boots.

Science is a philosophy of discovery. Intelligent design is a philosophy of ignorance. You cannot build a program of discovery on the assumption that nobody is smart enough to figure out the answer to a problem.

Astronomers do not commonly use Venereal, in favor of the less contagious-sounding Venutian. Blame the medical community, who snatched the word long before astronomers had any good use for it. I suppose you can't blame the doctors. Venus is the goddess of beauty and love, so she ought to be the goddess of its medical consequences.

Eventually, the Sun will swell to occupy the entire sky as its expansion subsumes the orbit of earth. Earth's surface temperature will rise until it matches the 3,000-degree rarified outer layers of the expanded Sun.... But not to worry. We will surely go extinct for some other reason long before this scenario unfolds.

Give a kid a book, and you change the world. In a way, even the universe.