Figure out for yourself what you want to be really good at, know that you'll never really satisfy yourself that you've made it, and accept that that's okay.

One could write a history of science in reverse by assembling the solemn pronouncements of highest authority about what could not be done and could never happen.

Age does not bring wisdom... but it does give perspective... and the saddest sight of all is to see, far behind you, temptations you've resisted.

Happiness consists in getting enough sleep. Just that, nothing more.

There ought not to be anything in the whole universe that man can't poke his nose into-that's the way we're built and I assume that there's some reason for that.

You can't conquer a free man; the most you can do is kill him.

Budget the luxuries first.