Burt Rutan

For the industry we're starting now, for suborbital flight, there is no destination, so the spacecraft you go up in has to be large and spacious. That's why SpaceShipTwo is much bigger than SpaceShipOne: It needs to be because you want those six people to be floating around and enjoying themselves.

When there's ever a breakthrough, a true breakthrough, you can go back and find a time period when the consensus was 'well, that's nonsense!' so what that means is that a true creative researcher has to have confidence in nonsense.