I have always looked on my businesses not just as money-making machines, but as adventures that can, I hope, make people better off.

People who think and say we more often than I are a lot more likely to succeed.

I've used the Phoenix Centrifuge to replicate what the body's going to go through on the flight up. I've also done some gravity tests with ZERO-G [a charter-flight service in Arlington, Va., that uses modified Boeing 727s to simulate weightlessness], which went great.

I set up this magazine called Student when I was 16, and I didn't do it to make money - I did it because I wanted to edit a magazine. There wasn't a national magazine run by students, for students. I didn't like the way I was being taught at school. I didn't like what was going on in the world, and I wanted to put it right.

If you look for the best in your employees, they'll flourish. If you criticize or look for the worst, they'll shrivel up. We all need lots of watering.

When I was young, every time I criticized someone, my mother would stand me in front of the mirror and say: 'The flaws you see in others are actually a reflection of yourself.' That taught me to pay close attention when I looked at others.

I don't live my life thinking about "if only." I just try to think positively about the future. We'll never know for certain what would have happened if we'd gone to Iraq. The important thing is that we've got to do everything we can to prevent other wars.