Do not use power to suppress opinions you think pernicious, for if you do the opinions will suppress you.

I would like to fly in space.Absolutely.That would be cool.I used to just do personally risky things， but now I’ve got kids and responsibilities， so I can’t be my own test pilot.That wouldn’t be a good idea.But I definitely want to fly as soon as it’s a sensible thing to do.

Don’t be afraid to fail. Be afraid not to try.