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800 Million Brains

A Harvard economist, Edward Glaeser, reviewed The Dominant Animal in the right-wing newspaper The New York Sun. Mixed in with some praise (and some not unreasonable criticism) was the following statement:

"The authors are particularly ardent in their opposition to population growth. It is true, as they point out, that there are environmental costs of having more people - all of us use natural resources and energy and bear some responsibility for greenhouse gas emissions. But there are also benefits, especially to the people being born. Each new person has a brain that might come up with new technologies that could reduce humanity's environmental impact. As an urban economist, my life's research has focused on the many ways in which we are all enriched by the people around us. Are there many parents who think that the world would have been better off if they had decided to have one less child?"

This is an ancient bromide. How many of you can see the most obvious error in it? That is that brains alone don't "come up with" new technologies. They need, among other things, good diets and good educations. The 800 million brains in sub-Saharan Africa, where food is often short and educational systems often marginal at best are a much smaller potential source of solutions than one-sixth as many in Japan. More on brains the next time. ---------- Paul R. Ehrlich is Bing Professor of Population Studies and Professor of Biological Sciences at Stanford University. He is the author of hundreds of scientific papers, and numerous books including The Population Bomb and Betrayal of Science and Reason (Island Press, 1997). His latest book is The Dominant Animal: Human Evolution and the Environment, which he co-authored with his wife Anne.