The great thing about working out at a gym is that if you put in effort, you get very obvious results. The same should be true of college. A professor’s job is to teach students how to see their minds growing in the same way they can see their muscles grow when they look in a mirror.

When you see yourself doing something badly and nobody's bothering to tell you anymore, that's a very bad place to be. Your critics are the ones telling you they still love you and care.

But I want her to grow up knowing that I was the first man ever to fall in love with her. I'd always thought the father/daughter thing was overstated. But I can tell you, sometimes, she looks at me and I just become a puddle.

I understand the arguments about how the billions of dollars spent to put men on the moon could have been used to fight poverty and hunger on Earth. But, look, I'm a scientist who sees inspiration as the ultimate tool for doing good. When you use money to fight poverty, it can be of great value, but too often, you're working at the margins. When you're putting people on the moon, you're inspiring all of us to achieve the maximum of human potential, which is how our greatest problems will eventually be solved. Give yourself permission to dream.

I'll take an earnest person over a hip person every day, because hip is short-term, earnest is long term.

It is not the things we do in life that we regret on our death bed. It is the things we do not.

Anybody out there who is a parent, if your kids want to paint their bedrooms,as a favor to me, let them do it. It'll be OK.