You can't have people making decisions about the future of the world who are scientifically illiterate. That's a recipe for disaster. And I don't mean just whether a politician is scientifically literate, but people who vote politicians into office.

There's no greater sign of the failure of the American educational system than the extent to which Americans are distracted by the possibility that Earth might end on December 21, 2012. It's a profound absence of awareness of the laws of physics and how nature works. So they're missing some science classes in their training in high school or in college that would empower them to understand and to judge when someone else is basically just full of it. Science is like an inoculation against charlatans who would have you believe whatever it is they tell you.

Grab something off the shelf that's on the spaceship-an ashtray, it doesn't matter what. Because I can tell you, if they flew here from another galaxy, no matter what you've pulled off the shelf, it'll be unlike anything we have on Earth.

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.

God displayed a sense of humor when he configured the region between our legs an entertainment complex built around a sewage system.

We already know the limits of Einstein's theories. From the centers of black holes at the very beginning of the universe - we call these singularities - Einstein's equations fail. In fact, people have joked that's where God is dividing by zero.

I knew Pluto was popular among elementary schoolkids, but I had no idea they would mobilize into a 'Save Pluto' campaign. I now have a drawer full of hate letters from hundreds of elementary schoolchildren (with supportive cover letters from their science teachers) pleading with me to reverse my stance on Pluto. The file includes a photograph of the entire third grade of a school posing on their front steps and holding up a banner proclaiming, 'Dr. Tyson - Pluto is a Planet!'