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.

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.

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.

You take the huge income that comes with a big gas tax, and you use it to pay off regressive taxes like the FICA [Federal Insurance Contributions Act] tax. You can help the poor in other ways besides giving them cheap gas. You want to send the message that people want to be as efficient as possible using gasoline until we can transition away from that need entirely.

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.

In pushing other species to extinction, humanity is busy sawing off the limb on which it perches.

Stanford may be the best university in the world, but you can get all the way through here without knowing where your food came from, without being able to say where we came from, without being able to give a coherent description of why the climate is changing and why we should be concerned about it. So I started teaching a course in human evolution and the environment that's open to all Stanford students, no prerequisites.