Space is about 100 kilometers away. That’s far away—I wouldn’t want to climb a ladder to get there—but it isn’t that far away. If you’re in Sacramento, Seattle, Canberra, Kolkata, Hyderabad, Phnom Penh, Cairo, Beijing, central Japan, central Sri Lanka, or Portland, space is closer than the sea.

There are so many adventures that you miss because you're waiting to think of a plan. To find them, look for tiny interesting choices. And remember that you are always making up the future as you go.

Space is about 100 kilometers away. That’s far away—I wouldn’t want to climb a ladder to get there—but it isn’t that far away. If you’re in Sacramento, Seattle, Canberra, Kolkata, Hyderabad, Phnom Penh, Cairo, Beijing, central Japan, central Sri Lanka, or Portland, space is closer than the sea.

I'm not sure why we romanticize 'young love,' or love in general...It just leads to the idea that either your love is pure, perfect and eternal, and you are storybook-compatible in every way with no problems, or you're LYING when you say 'I love you.

What people don't appreciate, when they picture Terminator-style automatons striding triumphantly across a mountain of human skulls, is how hard it is to keep your footing on something as unstable as a mountain of human skulls. Most humans probably couldn't manage it, and they've had a lifetime of practice at walking without falling over.

The universe is probably littered with the one-planet graves of cultures which made the sensible economic decision that there's no good reason to go into space-each discovered, studied, and remembered by the ones who made the irrational decision.

I think the really cool and compelling thing about math and physics is that it opens up entry to all these hypotheticals - or at least, it gives you the language to talk about them. But at the same time, if a scenario is completely disconnected from reality, it's not all that interesting.