Historically, things were moving in a pretty good direction until the Reagan presidency. And then it all got reversed. The Mexico City policy was instituted - the idea of wrecking the environment for this generation's profit and forgetting about our gets got firmly embedded. I'm sad to say the Clinton administration didn't turn it around and the Bush administration, well, I think they're the worst administration we've ever had, and I used to be a Republican.

We ought to take good care of everybody we have on the planet, but we ought to regulate the rate at which people join us. The old saying is, "It's the top of the ninth inning, and humanity has been hitting nature hard, but you've always got to remember that nature bats last."

To err is human, but to really foul things up you need a computer.

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.

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.

Too many cars, too many factories, too much detergent, too much pesticides, multiplying contrails, inadequate sewage treatment plants, too little water, too much carbon dioxide - all can be traced easily to too many people.

With taxes, if they aren't working right, we can change them with a stroke of the pen. It's basically a market-type mechanism. People make their own choices. You run the taxes, and you get the results.