Wetenschappelijke consensus is geen wetenschap
In een speech die in januari 2003 voor het CalTech instituut werd gehouden, beschrijft Michael Crichton hoe de wetenschap de afgelopen eeuw is verworden van een exacte methode om zaken te bewijzen naar, in heel veel gevallen, wetenschappelijke consensus zonder exacte bewijzen.
Hij noemt een groot aantal voorbeelden van deze ontwikkelingen: de jacht op tekenen van leven van aliens (SETI), de ‘nucleaire winter’, de ‘global warming’ en een ‘besmettelijke ziekte’ die achteraf een voedingsprobleem bleek te zijn. De grens tussen wetenschap en politiek vervaagt steeds meer volgens Crichton. Veel van deze consensus is na enkele jaren verdwenen of er is definitief van bewezen dat het niet waar was.
En de situatie rond de gevaren van ‘tweedehands rook’ toont aan hoe men op basis van junk science tot ingrijpende maatschappelijke ingrepen kan komen, zonder dat iemand maar durft te protesteren.
What, then, can we say were the lessons of Nuclear Winter? I believe the lesson was that with a catchy name, a strong policy position and an aggressive media campaign, nobody will dare to criticize the science, and in short order, a terminally weak thesis will be established as fact. After that, any criticism becomes beside the point. The war is already over without a shot being fired. That was the lesson, and we had a textbook application soon afterward, with second hand smoke.
In 1993, the EPA announced that second-hand smoke was “responsible for approximately 3,000 lung cancer deaths each year in nonsmoking adults,” and that it ” impairs the respiratory health of hundreds of thousands of people.” In a 1994 pamphlet the EPA said that the eleven studies it based its decision on were not by themselves conclusive, and that they collectively assigned second-hand smoke a risk factor of 1.19. (For reference, a risk factor below 3.0 is too small for action by the EPA. or for publication in the New England Journal of Medicine, for example.) Furthermore, since there was no statistical association at the 95% coinfidence limits, the EPA lowered the limit to 90%. They then classified second hand smoke as a Group A Carcinogen.
This was openly fraudulent science, but it formed the basis for bans on smoking in restaurants, offices, and airports. California banned public smoking in 1995. Soon, no claim was too extreme. By 1998, the Christian Science Monitor was saying that “Second-hand smoke is the nation’s third-leading preventable cause of death.” The American Cancer Society announced that 53,000 people died each year of second-hand smoke. The evidence for this claim is nonexistent.
In 1998, a Federal judge held that the EPA had acted improperly, had “committed to a conclusion before research had begun”, and had “disregarded information and made findings on selective information.” The reaction of Carol Browner, head of the EPA was: “We stand by our science….there’s wide agreement. The American people certainly recognize that exposure to second hand smoke brings…a whole host of health problems.” Again, note how the claim of consensus trumps science. In this case, it isn’t even a consensus of scientists that Browner evokes! It’s the consensus of the American people.
Meanwhile, ever-larger studies failed to confirm any association. A large, seven-country WHO study in 1998 found no association. Nor have well-controlled subsequent studies, to my knowledge. Yet we now read, for example, that second hand smoke is a cause of breast cancer. At this point you can say pretty much anything you want about second-hand smoke.
As with nuclear winter, bad science is used to promote what most people would consider good policy. I certainly think it is. I don’t want people smoking around me. So who will speak out against banning second-hand smoke? Nobody, and if you do, you’ll be branded a shill of RJ Reynolds. A big tobacco flunky. But the truth is that we now have a social policy supported by the grossest of superstitions. And we’ve given the EPA a bad lesson in how to behave in the future. We’ve told them that cheating is the way to succeed.
