I'm sort of optimistic about what we could do, but I'm very pessimistic about what we will do. I can't tell you that Al Gore's 10-year plan is impossible. I'm old enough to remember the Second World War - if we had a World War II-type mobilization, we might accomplish Gore's plan. In 1940 we were making tens of thousands of automobiles, and in 1941 we were making tens of thousands of airplanes. We mobilized as a nation. If we get that kind of mobilization as a nation or globally, then we could solve a lot of these problems.

I don't think scientists can dictate from above what we should do, because it's not a matter of scientific decision. If you want to have everybody living like a Beverly Hills millionaire, then 2 billion people might be too many. If we want to have a battery-chicken kind of world, with everybody having an absolute minimum diet, you might be able to support 10 billion.

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

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

People have not made the connection that the more of us there are, the more greenhouse gases go into the atmosphere. The Chinese have. They, unlike us, have a population policy. The right wingers just don't understand that the country they're in is probably the most overpopulated in the world, the one doing most of the destruction, and the one with horrendously bad leadership.

I kind of like carbon taxes because we already know how to apply them. We already have apparatus in place. When we talk about these other solutions - like a billion tons of iron filings in the ocean or putting sunshades between us and the sun - they're huge. We have no idea if they will work. We have no idea what their nasty consequences might be. And it's unlikely we can do them anyway.

In ten years [i.e., 1980] all important animal life in the sea will be extinct. Large areas of coastline will have to be evacuated because of the stench of dead fish.