I think a colony in space will take much longer than sci fiction writers think. It costs $10,000 to put a pound of anything into near earth orbit. That is your weight in gold. It costs about $100,000 a pound to put you on the moon. And it costs $1,000,000 a pound to put you on Mars.

I got a four year scholarship to Harvard, and while I was there they wanted to groom me for work in the Star Wars program designing weapons ignited by hydrogen bombs. I didn't want to do that. I thought about how many scientists had died in World War II.

No one knows when a robot will approach human intelligence, but I suspect it will be late in the 21st century. Will they be dangerous? Possibly. So I suggest we put a chip in their brain to shut them off if they have murderous thoughts.

Language and emotions are too easily misread. For example, laughing can mean many things: laughing with you or at you. Does that laugh reflect joy, anger, or that s/he's about to fire you? Too many jobs require complex feelings, pattern recognition, common sense, and the human touch.

There are many examples of old, incorrect theories that stubbornly persisted, sustained only by the prestige of foolish but well-connected scientists... Many of these theories have been killed off only when some decisive experiment exposed their incorrectness... Thus the yeoman work in any science, and especially physics, is done by the experimentalist, who must keep the theoreticians honest.

Faust was this mythical figure who sold his soul to the devil for unlimited power. The Japanese have made that Faustian bargain because they don't have coal, oil or hydro power.

Eternal life does not violate the laws of physics. After all, we only die because of one word: "error." The longer we live, the more errors there are that are made by our bodies when they read our genes. That means cells get sluggish. The body doesn't function as well as it could, which is why the skin ages. Then organs eventually fail, so that's why we die.