We know that if you have $20 million, it's better to buy a van Gough print than it is buy an executive jet, from the point of view of the environment. But when you start getting down, it's like the recycling question: What are things we can really afford to do, and how much pleasure do we get out of them? We haven't even started to have that discussion, and it's getting awfully late.

I see harm reduction as a way of engaging people as part of that path to recovery.

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.

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.

Organisms are starting to move in response to climate change all over the place. Bees are disappearing and we don't have many of the native pollinators left to replace them. We're in deep trouble; there's no question about it. But ecologists tend to think of something that's going to be bad in ten years as very fast, and of course, politicians only think of things in a two-, four-, six-year cycle.

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.

The mother of the year should be a sterilized woman with two adopted children