We keep what is valuable to us, what we cherish.

The person who failed often knows how to avoid future failures.

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.

Not everything needs to be fixed

We don't beat the reaper by living longer, but by living well, and living fully - for the reaper will come for all of us. The question is: what do we do between the time we're born and the time he shows up.

Brick walls are there for reason. And once you get over them-- even if someone has practically had to throw you over-- it can be helpful to others to tell them how you did it.

The questions are always more important than the answers.