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.

My first policy move would be to try to get a conversation going in the US about what people stand for and what we really want. Do we want to keep adding people to the world and to our country until we move to a battery-chicken kind of existence and then collapse? Or do we want to think hard about what really is valuable to us, and figure out how many people we can supply that to sustainably?

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.

The main thing is, and of course this is a pedant talking, we should start our education on these issues in kindergarten. Instead of saying, "See Spot run," we ought to say, "See the plant grow in the sun." We ought to explain what runs the weather in the third or fourth grade to start out with.

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.

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.

Most of the scientists I know think civilization is teetering on the brink of a global disaster. They just don't know when it's going to hit. I don't have the answer to that either. I'm scared as hell.