Population Levels Stabilizing, Says Author Fred Pearce On Jon Stewart (VIDEO)

Fred Pearce, the author of the new book "The Coming Population Crash and Our Planet's Surprising Future," talked to Jon Stewart last night about his surprisingly optimistic view of the Earth's future. He explained that there has been a huge population decrease in the past generation: women today have half as many children as they did a generation ago. This phenomenon is happening all over the world, Pearce said, not just in developing countries. And this self-made population control is very good for our planet and for our species.

In the book, Pearce looks at the history of environmentalism and population control, and shows that while in the past countries like China have enforced state-run population control, now people are doing it on their own. Why is this good for our society? "If we have an older society, we'll have a wiser society," Pearce suggested. The 20th century, he said, was a "teenage century," but the 21st will be much more mature. "By 2040, we should have a stable population," he said.

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