The moment when someone attaches you to a philosophy or a movement, then they assign all the baggage and all the rest of the philosophy that goes with it to you. And when you want to have a conversation, they will assert that they already know everything important there is to know about you because of that association. And that's not the way to have a conversation.

This fear factor, this war driver is a very strong one and it's been with the species ever since the beginning and it motivated the Great Wall of China. War can be aggressive or defensive, right? So it motivated the Great Wall of China. Our space program was reactive to Russia.

You can deceive yourself into thinking that America is a technological leader, but if you don't see what anyone else is doing you have no accurate assessment - you can't make an accurate assessment of where you fit and why. I consider our moving frontier in space as the anecdote to that downward trend.

When I wrestled, I would set aside the time to wrestle, so that in my mind it didn't interfere with my study time. If I'd say, "I'm going to study this many hours, then I'm going to go work out and wrestle," then when that time comes, you don't feel like you should be doing something else. That helped me psychologically. But otherwise? When I'm wrestling, I'm not studying the universe. And when I'm studying the universe, I'm not wrestling.

All tweets are tasty. Any tweet anybody writes is tasty. So, I try to have each tweet not simply be informative, but have some outlook, some perspective that you might not otherwise had.

Only when creative people take ownership of cosmic discovery will society accept science as the cultural activity that it is.

When you're a hammer (as the saying goes), all your problems look like nails. If you're a meteorite expert pondering the sudden extinction of boatloads of species, you'll want to say an impact did it. If you're an igneous petrologist, volcanoes did it. If you're into spaceborne bioclouds, an interstellar virus did it. If you're a hypernova expert, gamma rays did it.