Not wasting any water bottles is good. Not leaving the lights on is good. Turning the thermostat down in the winter, up in the summer, is good. But the best thing any of us in the developed world, especially in the United States, can be doing is talking about it.

We are just a speck, on a speck, orbiting a speck, in the corner of a speck, in the middle of nowhere.

If you decide to become a dancer on Broadway, never say who your favorite dance partner is, because members of the media will presume you never want to dance with anybody else.

Speaking of human computers, there is a guy named Art Benjamin, he's a human calculator. He says it's a skill he learned as a kid. Now he's a math professor at Harvey Mudd. He can find the square root of a six digit number in a few seconds. Practice.

The strange thing about grinding that might surprise many people is that you can grind things and shape them using materials that are generally somewhat softer than the thing you're grinding and shaping.

You stop planetary exploration, those people who do that extraordinary work are going to have to go do something else.

The Big Bang banged, and for some reason we’re here. And that’s astonishing. And that we can understand that, that’s the most astonishing.