Are you a Tigger or an Eeyore?

I'm dying, and I'm having fun.

And even though I did not reach the National Football League, I sometimes think I got more from pursuing that dream, and not accomplishing it, than I did from many of the ones I did accomplish.

The size of your audience doesn't matter. What's important is that your audience is listening.

Never underestimate the importance of having fun. I'm dying and I'm having fun. And I'm going to keep having fun every day because there's no other way to play it.

Brick walls are there for a reason. The brick walls aren't there to keep us out. The brick walls are there to show us how badly we want things.

I understand the arguments about how the billions of dollars spent to put men on the moon could have been used to fight poverty and hunger on Earth. But, look, I'm a scientist who sees inspiration as the ultimate tool for doing good. When you use money to fight poverty, it can be of great value, but too often, you're working at the margins. When you're putting people on the moon, you're inspiring all of us to achieve the maximum of human potential, which is how our greatest problems will eventually be solved. Give yourself permission to dream.