I don't see anything beneficial about the US spending 100 billion dollars to go back to the moon unless we learn something new that will help us go to the moons of Saturn okay and so we ought to use that to breed new breakthroughs and to test new breakthroughs and to fund it.

When you have a transportation system that the price of propellant is essentially negligible something is very wrong. If you look at any other transportation system, a car, a motorcycle, a train, an oil tanker, an airliner, you name it; about a quarter to a third of the operating cost is buying the propellant.

Testing leads to failure, and failure leads to understanding

A true creator researches how to have confidence in nonsense.

There will be a new industry, and we are just now in the beginning. I will predict that in twelve or fifteen years there will be tens of thousands, maybe even hundreds of thousands of people, that fly and see that black sky.

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.

Everything looks nonsensical before it works.