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Absolute Certainty Is Not Scientific

Global warming alarmists betray their cause when they declare that it is irresponsible to question them.


This belief in absolute certainty is fundamentally what has bothered me about the scientific debate over global warming in the 21st century, and I am hoping it will not characterize the discussions at the United Nations Climate Change Conference in Durban, South Africa, currently under way.

Bjorn Lomborg on the ClimateGate 2.0 e-mail scandal and World AIDS Day.

Reading Mr. Mumma's statement, I thought immediately of physicist Niels Bohr, a Nobel laureate, who said, "Anyone who is not shocked by quantum theory has not understood it." To which Richard Feynman, another famous physicist and Nobel laureate, quipped, "Nobody understands quantum mechanics."



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I was one of many scientists on several panels in the 1970s who reviewed the results from the Viking Landers on Mars, the ones that were supposed to conduct experiments that would help determine whether there was or wasn't life on that planet. I don't remember anybody on those panels talking in terms of absolute certainty. Instead, the discussions were about what the evidence did and did not suggest, and what might be disprovable from them and from future landers.

I was also one of a small number of scientists—mainly ecologists, climatologists and meteorologists—who in the 1970s became concerned about the possibility of a human-induced global warming, based on then-new measurements. It seemed to be an important scientific problem, both as part of the beginning of a new science of global ecology and as a potentially major practical problem that nations would have to deal with. It did not seem to be something that should or would rise above standard science and become something that one had to choose sides in. But that's what has happened.

Some scientists make "period, end of story" claims that human-induced global warming definitely, absolutely either is or isn't happening. For me, the extreme limit of this attitude was expressed by economist Paul Krugman, also a Nobel laureate, who wrote in his New York Times column in June, "Betraying the Planet" that "as I watched the deniers make their arguments, I couldn't help thinking that I was watching a form of treason—treason against the planet." What had begun as a true scientific question with possibly major practical implications had become accepted as an infallible belief (or if you're on the other side, an infallible disbelief), and any further questions were met, Joe-McCarthy style, "with me or agin me."


It is helpful to go back to the work of the Wright brothers, whose invention of a true heavier-than-air flying machine was one kind of precursor to the Mars Landers. They basically invented aeronautical science and engineering, developed methods to test their hypotheses, and carefully worked their way through a combination of theory and experimentation. The plane that flew at Kill Devil Hill, a North Carolina dune, did not come out of true believers or absolute assertions, but out of good science and technological development.

Let us hope that discussions about global warming can be more like the debates between those two brothers than between those who absolutely, completely agree with Paul Krugman and those who absolutely, completely disagree with him. How about a little agnosticism in our scientific assertions—and even, as with Richard Feynman, a little sense of humor so that we can laugh at our errors and move on? We should all remember that Feynman also said, "If you think that science is certain—well that's just an error on your part."

Mr. Botkin, president of the Center for the Study of the Environment and professor emeritus at the University of California, Santa Barbara, is the author of the forthcoming "Discordant Harmonies: Ecology in a Changing World" (Oxford University Press).

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