All scientists who've looked at it know we have to phase away from burning fossil fuels. That means we've got to put a lot of effort into alternate energy technologies, but we're still subsidizing fossil fuels and not subsidizing most of the alternatives. It's not going to be an easy transition.

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.

I don't like the idea of teaching religion in schools, and creation is not my thing, but that's a trivial point compared to saving the creation. I'd much rather have half of the people in the country be creationists and work really hard to save the creation than have everybody be evolutionists and be destroying the planet.

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.

Your children should have it impressed upon them that their adult life-style will bear very little resemblance to yours and that they should now be acquiring knowledge, skills, values, and tastes that will sustain them in less materially affluent circumstances. On the other hand, the fresh insights and imaginations of your children may help you find a viable future while there's still time.

Anyone who opposes methods to control the birth rate, is automatically voting in favour having the death rate go up.

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.