American Scientist

To the Editors:

The tone of Vaclav Smil's obituary of Garrett Hardin dismayed me (Macroscope, January–February).

Dr. Smil, a former demographer, dismisses Dr. Hardin's concern that the world's population will reach "50 billion people." I never knew Dr. Hardin to claim this high figure. Inquiring of Dr. Smil, I was sent a short piece by Garrett entitled "Carrying Capacity and Quality of Life" from the Spring 1991 edition of The Social Contract. Fifty billion is an estimate of the "physical carrying capacity" of the globe by a "competent physicist" (not identified). In context, Dr. Hardin is writing about "cultural carrying capacity," which is always less than the physical carrying capacity, the quality of life and quantity of life being ultimately inversely related. Thomas Malthus noted that there should be no more people in a country than can "daily enjoy a glass of wine and piece of beef for dinner." So to Garrett, even a maximum world population at 10 billion, the current forecast per Dr. Smil, implies great stress on the cultural carrying capacity.

Dr. Smil espouses the politically correct position that excessive consumption is more the problem than global population, which he posits as eventually self-regulating. But how? Consumption and total population are both problems; it is just safer to attack the former. Dr. Hardin, to his credit, was always more forthright.

Dr. Smil, an expatriate of what is now the Czech Republic, expresses an inconsistent position when discussing Dr. Hardin's views on immigration (to the United States). If consumption is the greater problem, bringing well over 1 million people annually from the lower-consumption Third World to the higher-consumption United States aggravates and magnifies stress on the biosphere. (Also, the immigration lessens the pressure on the Third World nations to deal with their own population problems.)

While Dr. Smil finds "it no easy task to understand this man," the constraints of late-20th-century political correctness may be the limiting factor. Dr. Hardin had the temerity and originality to address issues more forthrightly than is currently the vogue. He will be missed.

William E. Murray, Jr.
Portola Valley, California