If Neptune were analogized with a Chevy Impala in mass, then how big is pluto compared to that? Pluto would be a matchbox car sitting on the curb.

Asteroids have us in our sight. The dinosaurs didn't have a space program, so they're not here to talk about this problem. We are, and we have the power to do something about it. I don't want to be the embarrassment of the galaxy, to have had the power to deflect an asteroid, and then not, and end up going extinct.

When you're enlightened, you don't have to reference other people, because you yourself are enlightened. And that's a better Earth. People can make more informed decisions politically, culturally, personally.

Lots of people think, well, we're humans; we're the most intelligent and accomplished species; we're in charge. Bacteria may have a different outlook: more bacteria live and work in one linear centimeter of your lower colon than all the humans who have ever lived. That's what's going on in your digestive tract right now. Are we in charge, or are we simply hosts for bacteria? It all depends on your outlook.

Our planet has been around only for four and a half billion years. Let's imagine a planet that has life on it such as life is on Earth and it's seven billion years old. Let's say that planet evolved intelligence. Well, that intelligence would be way more advanced than what we call intelligence here on Earth. How long has intelligence been around on Earth as we've come to define it?

You should chose your heroes a-la carte. Picking and choosing from one and then another, thereby assembling a kind of composite hero. That way when you discover something reprehensible about any one of them it matters nothing to you because that's not the part of them that piqued your interest.

New generations of humans inherit the acquired discoveries of generations past, allowing cosmic insight to accumulate without limit. Each discovery of science therefore adds a rung to a ladder of knowledge whose end is not in sight because we are building the ladder as we go along. As far as I can tell, as we assemble and ascend this ladder, we will forever uncover the secrets of the universe - one by one.