Publicly and among themselves biologists rightly celebrate the diversity of life on Earth... At the end of the day, however, their confession is heard by no one: they work with a single scientific sample-life on Earth.

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.

Everything we do understand about the universe - the periodic table of elements, Einstein's laws, Newton's laws, all of chemistry, all of biology - that's 4 percent of the universe. We got to the moon on the 4 percent we do understand. We landed on Mars on the 4 percent we do understand. So the day we crack the nut of the rest of that 95 percent... Oh my gosh.

When I needed to overcome the low expectations of others or the bias that would be expressed in one circumstance or another, I'd keep on keeping on. And I climb over the obstacle, go around it, dig under it, fly over it. That's what kept me going. Otherwise I would have never been an astrophysicist.

There is no greater education than one that is self-driven.

If the Sun exploded, we wouldn't know about it for 8 minutes and 20 seconds. Light and gravity take that long to reach us. Then we would vaporize.

I'm an educator, and I'm a scientist, and I speak what is objectively true. And if that offends you, I can try to have a conversation with you to ask why it offends you, and tell you why objective truth should not offend you because that's how the world works.