Overall, The Population Bomb was probably too optimistic. I was writing about climate change - Anne and I actually wrote the book. We discussed whether or not you'd have to take a gondola to the Empire State Building, and that sort of thing, but we didn't know at the time whether the climate change would be in the direction of heating or cooling. We just didn't know enough about it.

Woman should have the choice whether to have an abortion or not, but I like what Bill Clinton said: It ought to be safe and rare. You don't want to offend people with it. You try and do as much as you can to let people be different, but also to try and protect them from things that they think are bad. And it's worth all of us giving a little.

It turns out the population issue is an easier thing to deal with than the consumption issue. Some obvious extremes in consumption we can deal with. The standard cure for a stuttering economy is to go out and buy an SUV and three more refrigerators. That's obviously not the way to go.

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.

If we were redesigning around people instead of around automobiles, which I think the market is more or less going to do, although too slowly, than I'd be a lot cheerier.

Recycling helps make people feel involved, and in some cases can be useful. Although you've got to do careful life history studies of what you're recycling. If all you're doing is recycling - if you've got three automobiles, and 10 children, and a 7,000-square-foot dot-com palace and second home up in the mountains that has to be heated - the recycling isn't making much difference.

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.