I thought if the climate was heating that CO2 was the only forcing, and it would be late in the century before we had trouble. Now that we know about the other half of the forcing, it's obvious that the trouble is coming much sooner.

We've all got to get together and demand something better out of our government and out of each other. We've got a system that's making us working harder, and isn't giving us satisfaction. We've got to sit down and decide what the hell we really want to be as human beings.

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

So, regarding the time frame, I'm only too willing to admit that my crystal ball, like everybody else's, is cracked. If I could predict precisely, I would have started predicting the stock market and would now be living with a bunch of young women on Bora Bora, having bought it.

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.

For example, I'm a great fan of pornography, but I don't see any reason not to restrict it so that people walking down the street who hate pornography don't have full color pictures outside of movie theaters. Let them be in a different district. I'm kidding about pornography, but you get the point.

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.