I like to call the difference between research and development. Some people use that interchangeably. They'll say R&D. They're two totally different things.

In 12 or 15 years, there will be routine, affordable space tourism not just in the U.S. but in a lot of countries.

Usually the wacky people have the breakthroughs. The smart people dont.

A NASA astronaut and a Russian cosmonaut can't be creative. He has to follow a predetermined detailed checklist written by an engineer and if he gets a little creative he'll never fly again.

I believe that research, that you can claim that you're doing research only if half of the people, and I'm talking about half of the experts, believe that the goal is impossible.

A true creator researches how to have confidence in nonsense.

NASA's myriad failures are in many ways the natural consequence of a catastrophic combination of bureaucracy, monopoly, and a calcifying aversion to the kind of risk necessary for innovation.

Everything looks nonsensical before it works.

Testing leads to failure, and failure leads to understanding

I have a hunch the most important reason we're going to space is not known now.

Look at the aerospace industry as it was just after the Kennedy talk. We were hiring like crazy. We were trying to get people graduated from college. Hey, you got to go to the program. We need you.

Isn’t it strange how a lamb can feel like a lion when comparing itself to a mouse, whereas a lion feels like a lamb when measuring itself against dragons?

O divine art of subtlety and secrecy! Through you we learn to be invisible, through you inaudible, and hence we can hold the enemy's fate in our hands.

I guess it’s a good thing that we don’t know what we don’t know

Heckling is an act of cowardice. If you want to speak, get up in front of the microphone and speak, don't sit in the dark hiding. It's easy to hide and shout and waste people's time.

There is no sin but ignorance.

People always say to me, "What if it doesn't work?" If it doesn't work, we redouble our effort. We're not going to cry like a bunch of babies. We're going to redouble our effort.

You would be surprised at the lengths you will go to believe the best about someone if you truly love him

I like to believe that everyone is born with the same skill set, and that it is the influences that one comes upon.

I think when the world makes you feel rejected, you bite back.

After a time, civil servants tend to become no longer servants and no longer civil.