As areas of knowledge grow, so too do the perimeters of ignorance.

The universe has really never made things in ones. The Earth is special and everything else is different? No, we’ve got seven other planets. The sun? No, the sun is one of those dots in the night sky. The Milky Way? No, it’s one of a hundred billion galaxies. And the universe - maybe it’s countless other universes.

In the animal kingdom, one of the keys to survival is to outwit your enemies. And when you're surrounded by carnivores, one of the best strategies is to fade into the background and disappear.

I have a personal philosophy in life: If somebody else can do something that I'm doing, they should do it. And what I want to do is find things that would represent a unique contribution to the world-the contribution that only I, and my portfolio of talents, can make happen. Those are my priorities in life.

When students cheat on exams, it's because our school system values grades more than students value learning.

Seventy percent of Earth's surface is water and over 99 percent is uninhabited, so you would expect nearly all impactors to hit either the ocean or desolate regions on Earth's surface. So why do movie meteors have such good aim?

Research in education has shown that we remember field trips long into adulthood. I remember visiting the post office in second grade and looking at the sorting machine. I have vivid memories of that, when I don't even remember the name of the teacher who took me.