In pushing other species to extinction, humanity is busy sawing off the limb on which it perches.

Sometimes I think the Congress feels that if you only decided tomorrow to switch to wind power that in two years we'd be getting 80 percent of our electricity from wind power. It's nonsense. Normally it takes 20 to 30 years after a new technology is demonstrated and deployed before it powers even 15 or 20 percent of the grid. There's this long lag time, and we haven't even decided which directions to go.

By 1985 enough millions will have died to reduce the earth's population to some acceptable level, like 1.5 billion people.

There are a lot of signs. One of the things that makes me most nervous is the disappearance of the frogs. They're going downhill all over the planet. Frogs are susceptible to all kinds of problems, because they require water to breed and their skin is very porous. Their condition is nerve racking.

Most of the scientists I know think civilization is teetering on the brink of a global disaster. They just don't know when it's going to hit. I don't have the answer to that either. I'm scared as hell.

People have to decide, first of all, how they'd like to live, and how secure they want to be from disaster. After that, scientists can help determine what would be necessary to achieve that.

We're never all going to agree with each other. We have to learn to value the diversity. It's one of the presumable principles of our government that isn't followed nearly enough - one of the jobs of the majority is to try and make the minority feel comfortable.