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

If each dead person became a ghost, there'd be more than 100 billion of them haunting us all. Creepy, but cool.

When scientifically investigating the natural world, the only thing worse than a blind believer is a seeing denier.

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

But to carve the Grand Canyon, Earth required millions of years. To excavate Meteor Crater, the universe, using a sixty-thousand-ton asteroid traveling upward of twenty miles per second, required a fraction of a second. No offense to Grand Canyon lovers, but for my money, Meteor Crater is the most amazing natural landmark in the world.

Typically, when you look for role models, you want someone who has your interests and came from the same background. Well, look how restricting that is. What people should do is take role models a la carte. If there's someone whose character you appreciated, you respect that trait.

Passion is what gets you through the hardest times that might otherwise make strong men weak, or make you give up.