I don't want people to say, 'Something is true because Tyson says it is true.' That's not critical thinking.

When Kennedy said, 'Let's go to the moon,' we didn't yet have a vehicle that wouldn't kill you on launch. He said we'll land a man on the moon in eight years and bring him back. That was an audacious goal to put forth in front of the American people.

By the way, how much does NASA cost? It's half a penny on a dollar. Did you know that? ... The most powerful agency on the dreams of a nation is currently underfunded to do what it needs to be doing, and that's making dreams come true ... How much would you pay for the universe?

I try to keep this in mind when tied in to a rope 75 feet up in a tree... The history of ideas about our place in the universe has been a long series of let-downs for those who like to believe we are special.

The Big Bang Theory: When geeky scientists can be main characters in a hit prime time series, you know there's hope for the world.

Perhaps these ancient observatories like Stonehenge perennially impress modern people because modern people have no idea how the Sun, Moon, or stars move. We are too busy watching evening television to care what's going on in the sky.

For me, I am driven by two main philosophies, know more today about the world than I knew yesterday. And along the way, lessen the suffering of others. You'd be surprised how far that gets you.