"Keeping score of old scores and scars, getting even and one-upping, always make you less than you are."

"When in doubt, duck."

"Education's purpose is to replace an empty mind with an open one."

"There is never enough time, unless you're serving it."

"You can judge the character of others by how they treat those who can do nothing to them or for them."

"It's so much easier to suggest solutions when you don't know too much about the problem."

"If you're not happy without it, you'll never be happy with it."

"If you're not scared or angry at the thought of a human brain being controlled remotely, then it could be this prototype of mine is finally starting to work."

"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

"When you learn, teach. When you get, give."

"My most important piece of advice to all you would-be writers: when you write, try to leave out all the parts readers skip."

"A friend is a present you give yourself."