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Countering the distortion of environmental science.

The Two Simon Bets

One of the most misunderstood events in environmental politics was "the bet" between Paul Ehrlich , physicists John Harte and John Holdren, and Julian Simon. The facts of that incident are explained in Betrayal of Science and Reason, by Paul and Anne Ehrlich, (Island Press, 1996, pp. 100-104), excerpted below:

"In 1990 [Julian Simon] won a much publicized ten-year bet with ecologist Paul Ehrlich [and physicists John Harte and John Holdren] .wagering correctly that the price of a basket of five metals would fall between 1980 and 1990 (meaning supplies became more plentiful)." (Norman Myers and Julian Simon, 1994)[34] "[The bet affirmed] cornucopian claims that the supply of resources is becoming more abundant, not more scarce." (Ronald Bailey, 1993)[35]

In 1980, Julian Simon repeatedly challenged environmental scientists to bet against him on trends in prices of commodities, asserting that humanity would never run out of anything.[36] Paul and the other scientists knew that the five metals in the proposed wager were not critical indicators and said so at the time.[37] They emphasized that the depletion of so-called renewable resources--environmental resources such as soils, forests, species diversity, and groundwater--is much more indicative of the deteriorating state of society's life-support systems.

Nonetheless, after consulting with many colleagues, Paul and Berkeley physicists John Harte and John Holdren accepted Simon's challenge in late 1980, jointly betting a total of $1000 ($200 each on five metals),[38] rather than listen to him charge that environmental scientists were unwilling to put their money where their mouths were. Perhaps it was a mistake, but it can be quite satisfying to skewer an adversary on his own terms, and they thought they had a good chance of winning.

Prices of all five metals (chromium, copper, nickel, tin, and tungsten) had gone up between 1950 and 1975. But the prices of three of the five went down in the 1980s, in part because a recession in the first half of that decade slowed the growth of demand for industrial metals worldwide. Ironically, a prominent reason for the slower industrial growth was the doubling of world oil prices in 1979.[39] Indeed, the price of oil probably was a factor in the prices of metals in both years, being unprecedentedly high in 1980 and unprecedentedly low in 1990. Paul and his colleagues ended up paying a small sum on the bet, even though the price of a ton of copper (Simon's favorite example) had risen in constant 1980 dollars from $1970 per ton in 1975 to $2166 in 1989.[40]

Simon issued a challenge for a second bet in 1995. In an essay in the San Francisco Chronicle, he claimed that "Every measure of material and environmental welfare in the United States and in the world has improved rather than deteriorated. All long-run trends point in exactly the opposite direction from the projections of the doomsayers"[41] (our emphasis). Simon asserted that everything will get better; he wanted ecologists to bet that "any trend pertaining to material human welfare" will get worse.
Paul and Stephen Schneider, a climatologist at Stanford University, offered to bet Simon $1000 per trend that each of the following fifteen continental and global indicators "pertaining to human welfare" will worsen over the next decade.[42]

1. The three years 2002-2004 will on average be warmer than 1992-1994. (Rapid climate change associated with global warming could pose a major threat of increasing droughts and floods.)

2. There will be more carbon dioxide in the atmosphere in 2004 than in 1994. (Carbon dioxide is the most important greenhouse gas driving global warming.)

3. There will be more nitrous oxide in the atmosphere in 2004 than in 1994. (Nitrous oxide is another greenhouse gas that is increasing due to human disruption of the nitrogen cycle.)

4. The concentration of ozone in the lower atmosphere (the troposphere) will be greater in 2004 than in 1994. (Tropospheric ozone is a component of smog that has important deleterious effects on human health and crop production.)

5. Emissions of the air pollutant sulfur dioxide in Asia will be significantly greater in 2004 than in 1994. (Sulfur dioxide in the atmosphere becomes sulfuric acid, the principal component of acid rain, and it is associated with direct damage to human health, forests, and crops.)

6. There will be less fertile cropland per person in 2004 than in 1994. (Much of Earth's best farmland is being paved over, but even if it weren't, population growth will reduce per-capita acreage.)

7. There will be less agricultural soil per person in 2004 than in 1994. (Erosion virtually everywhere far exceeds rates of soil generation.)

8. There will be on average less rice and wheat grown per person in 2002-2004 than in1992-1994. (Rice and wheat are the two most important crops consumed by people.)

9. In developing nations there will be less firewood available per person in 2004 than in 1994. (More than a billion people today depend on fuelwood to meet their energy needs.)

10. The remaining area of virgin tropical moist forests will be significantly smaller in 2004 than in 1994. (Those forests are the repositories of some of humanity's most precious living resources, including the basis for many modern pharmaceuticals worldwide.)

11. The oceanic fisheries harvest per person will continue its downward trend and thus in 2004 will be smaller than in 1994. (Overfishing, ocean pollution, and coastal wetlands destruction will continue to take their toll.)

12. There will be fewer plant and animal species still extant in 2004 than in 1994. (Other organisms are the working parts of humanity's life support systems.)

13. More people will die of AIDS in 2004 than did in 1994 (as the disease takes its toll of already infected individuals, continues to spread in Africa, and takes off in Asia.)

14. Between 1994 and 2004, sperm counts of human males will continue to decline and reproductive disorders will continue to increase. (Over the past fifty years, sperm counts worldwide may have declined as much as 40 percent. Paul and Steve bet this trend will continue due to the widespread use and environmental persistence of hormone-disrupting synthetic organic chemical compounds.)

15. The gap in wealth between the richest 10 percent of humanity and the poorest 10 percent will be greater in 2004 than in 1994.

We do not argue that all environmental trends are unfavorable, simply that many of the most important ones are very unfavorable and thus demand prompt attention. It is sensible to focus on the things that need fixing rather than on those that don't. Virtually all long-term trends have short-term fluctuations; thus in response to Simon's challenge, Steve and Paul picked fifteen trends to avoid having a statistical fluke decide this bet.[43]

Yet Simon refused to accept the wager, going back on his original challenge by saying he will gamble only on "direct" measures of human welfare such as life expectancy, leisure time, and purchasing power.[44] Steve and Paul refused to let Simon change his bet for several reasons. First, life expectancy is determined by a complex interaction of many factors, including infant and child nutrition, availability and sophistication of medical services, cleanliness of air and water, and other elements of environmental quality. Also, while life expectancies may temporarily (i.e., between 1995 and 2005) continue to rise, that increase may well not be sustainable.

Steve and Paul deliberately limited their list to negative environmental or social trends because they are the ones that need to be fixed regardless of whether other trends are positive. Policies and practices are established by area by area. Life expectancy is more likely to increase (certainly over the long term) if negative trends such as those listed by Steve and Paul could be turned around by wise policy actions. No doubt it would be higher today if those trends had been reversed twenty years ago.

A second reason for not letting Simon off the hook is that he, not the "doomsayers," prominently declared "all trends" to be positive. Steve and Paul indulged in this betting foolishness in the first place in the hope of (1) getting Simon to retract his socially dangerous and scientifically ridiculous assertion that all material or environmental welfare trends were positive, (2) getting Simon to contribute $10,000-15,000 to the environmental charities they select in 2005 to receive the winnings, or (3) getting the public to see that Simon blusters and asserts but won't back up his own rhetoric when seriously challenged. The third outcome was the one obtained.

Bets, of course, are a poor way to settle disputes about the human future, but Paul and his colleagues have been compelled to make two of them in an effort to counter the inaccurate information spread by Simon and others.[45] Scientists in all nations must be ready to counter the arguments of brownlash spokespersons who misinterpret information on what is happening to the environment. Such misinformation gives aid and comfort to those who promote unrestrained population growth and reckless consumption and in so doing threaten society's life-support systems. Rational scholarly discourse is all very well, but it does not hold sway where controversies affecting public policies are concerned.

The fifteen wagers Paul and Steve offered Simon are ones we would love to lose. In fact, we will keep on doing everything in our power to make that happen. But the complacent outlook and inaccuracies spread by Simon tragically increase the chances that we will win the bet--while humanity loses. We can only hope the wagers will cause Simon and others to reconsider the risks they so blithely encourage the public to take by promoting the fantasy that indefinite growth is both possible and benign.


34. N. Myers and J. Simon, 1994, Scarcity or Abundance? A Debate on the Environment, W. W. Norton, New York, back flap copy.

35. R. Bailey, 1993, Eco-Scam: The False Prophets of Ecological Apocalypse, St. Martin's Press, New York, p. 54.

36. See, e.g., J. Simon, 1981, The Ultimate Resource, Princeton University Press, Princeton, NJ, p. 27.

37. J. Holdren, J. Harte, P. Ehrlich, and A. Ehrlich, 1980, Bad news: Is it true? Science 210:1296-1297.

38. The bet was made on real (adjusted for inflation) prices.

39. Simon himself admitted he was lucky in a letter to Ehrlich, Harte, and Holdren in October 1989. Crowing in advance about his victory, he said, "I have been lucky that this particular period coincided so nicely with my argument."

40. World Resources Institute, 1992, World Resources Report 1992-1993, Basic Books, New York.

41. J. Simon, 1995, "Earth's doomsayers are wrong," San Francisco Chronicle, 12 May.

42. P. Ehrlich and S. Schneider, 1995, "Wagering on global environment," San Francisco Chronicle, 18 May.

43. In the first bet, prices increased for two metals and fell for three, an outcome that easily could have been changed by chance. On the direction of the trends in 2005, Paul and Steve agreed to accept the verdict of a panel of scientists chosen by the president of the National Academy of Sciences. Referees would have been necessary in some cases, since terms like "significantly" (e.g., in item 10 of the proposed wager) and estimates of such things as losses of agricultural soils involve questions of judgement. But there is an empirical basis on which competent scientists could make reasonable judgements. The bet would have been binding on Ehrlich's and Schneider's heirs, and their winnings would have gone to non-profit organizations dedicated to preserving environmental quality and human well-being.

44. Simon now tells reporters that he wants to bet only that the net effects of human activities will be positive, such as an increase in life expectancy, and accuses Steve and Paul of being unreasonable for not accepting this new kind of bet (see, e.g., C. Petett, 1995, "2 Stanford scholars take on rosy economist," San Francisco Chronicle, 18 May). He claims that the Ehrlich-Schneider list dwells on aspects of our environment for which the connection to human welfare is questionable. Of course, the scientific community (of which he claims to represent the consensus) doesn't seem to find the list so "questionable"--see appendix B ("The Scientific Consensus," from Population Summit of the World's Scientific Academies, 1993, National Academy of Sciences, Washington, DC.)

45. The wager has been taken quite seriously by the media and the public in western countries; see, e.g., J. Tierney, 1990, "Betting the planet," New York Times Magazine, 2 December; New Scientist, 1995, "Apocalypse tomorrow . . . " 3 June, p. 3; R. Mestel, 1995, "Doomsters take on global bet," New Scientist, 3 June, p. 5.


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Updated 16 March 2005