It's pointless to have a nice clean desk, because it means you're not doing anything.

For most of human history, we could only watch, like bystanders, the beautiful dance of Nature. But today, we are on the cusp of an epoch-making transition, from being passive observers of Nature to being active choreographers of Nature. The Age of Discovery in science is coming to a close, opening up an Age of Mastery.

Beyond work and love, I would add two other ingredients that give meaning to life. First, to fulfill whatever talents we are born with. However blessed we are by fate with different abilities and strengths, we should try to develop them to the fullest, rather than allow them to atrophy and decay. ... Second, we should try to leave the world a better place than when we entered it.

Until computers and robots make quantum advances, they basically remain adding machines: capable only of doing things in which all the variables are controlled and predictable. Robots are bad at pattern recognition and certainly at common sense. That's why computers can beat humans in chess but can't have even a basic conversation with a six-year-old.

I agree, along with Carl Sagan, that we should eventually become a two planet species. Life is too precious to place on a single planet.

I believe that science is the engine of prosperity, that if you look around at the wealth of civilization today, it's the wealth that comes from science.

Today's clunky smart glasses will be replaced by smart contact lenses. We'll command them by voice, blinking, or even thinking, to interact visually in 3-D with the Internet.