Thursday, November 19, 2009

Denialism

As someone who communicates science for a living, I frequently struggle to understand the widespread distrust of scientific evidence in public and private decisions. I was looking forward to some enlightenment in The New Yorker writer Michael Specter's new book, Denialism: How Irrational Thinking Hinders Scientific Progress, Harms the Planet, and Threatens Our Lives.

I was disappointed. The book scarcely addresses the origins of denialism, or even, as the subtitle advertises, its consequences. Instead, it reads as a cobbled-together series of feature articles, all too long to be called vignettes. The pieces are mostly interesting, well researched and well written, but they include a lot of background material that is peripheral to denialism. As to where the attitude comes from, Specter offers only speculation.

Specter is unlikely to make many converts to "rational thinking," since he frequently comes across as a cheerleader for progress, even as he acknowledges its risks and uncertainties. For example, near the close of his 21-page introduction, he shares a letter from a New Yorker reader: "…the question remains, will this generation of scientists be labeled the great minds of the amazing genetic-engineering era, or the most irresponsible scientists in the history of the world? With the present posture of the scientific community, my money, unfortunately, is on the latter." I regard this is a valid question, but Specter dismisses it: "Those words might as well have been torn from a denialist instruction manual: change is dangerous; authorities are not to be trusted; the present 'posture' of the scientific community has to be one of collusion and conspiracy." He doesn't seem to allow for reckless overconfidence.

Specter doesn't address climate change, which is the only big issue where denialism (as opposed to progress) threatens to "harm the planet." Cynics will note that it's also the issue where denialism promotes corporate interests, rather than opposing them. But the various chapters cover a wide range of topics.

In Vioxx and the Fear of Science, Specter reviews Merck's coverup of the heart risks of their pain medication, Vioxx. This sorry episode has been discussed elsewhere, for example in Melody Peterson's Our Daily Meds, but on its face it has little to do with irrational denial. In fact, in this case, distrust of pharmaceutical companies and the FDA are quite well founded. But in the final section of the chapter that reads like an afterthought, Specter blames much of the public's disregard for scientific evidence such betrayals of trust, although he gives little evidence for this connection.

Specter also uses the Vioxx case to illustrate a common problem: undue attention to acute harms rather than small, distributed benefits. He even argues that the thousands of deaths from Vioxx might have been a reasonable price to pay for its pain relief benefits to millions. Such weaknesses in risk assessment certainly skew many policy and private decisions. But our oft-lamented poor balancing of accepted risks and benefits strikes me as somewhat distinct from denialism, in which scientific evidence for benefit or harm is dismissed entirely.

Both denialism and poor weighing of pros and cons also come to play into the second chapter, Vaccines and the Great Denial. Specter makes it clear there is virtually no science supporting the anti-vaccine movement, and documents the highly misleading selective quotation of a government report in Robert Kennedy's famous Rolling Stone story. This is an easy case to make, but he does it convincingly.

In The Organic Fetish, Specter combines two distinct food-related issues. He shows convincingly that the benefits of "organic" foods are less clear-cut than advocates would like to believe, although I prefer Michael Pollan's wonderful book, The omnivore's dilemma: a natural history of four meals. But Specter's denialism them lets him zig-zag erratically between organic and genetically modified (GM) foods. He compelling despairs over African nations' rejecting GM foods for their starving populations, but he is too willing to accept the standard, long disproven reassurances about the limited spread of modified foods. Still, Specter resoundingly dispels the mythical distinction between modern modifications and those that have been accepted for decades or millennia.

Specter's chapter on food supplements and alternative medicine, The Era of Echinacea, also has an easy target, although he notably includes multivitamin supplements among the snake oils. But again, his discussion lacks a clear explanation of why many people trust these uncontrolled additives more than they do the tightly-regulated products of the pharmaceutical industry.

Race and the Language of Life combines two disparate topics. Specter's discussion of the complex role of genetics in disease is impressively thorough and accurate, and he gives it a human touch with his own genetic testing. But he also invokes the importance of genetics to support the use of race in medicine. Although Specter is no doubt correct that race is often avoided for political reasons, there is a legitimate scientific question that he fails to clarify: how much of the genetic variation in medical response can be explained with traditional notions of race? If within-group variation is large and the differences between groups are largely statistical, the divisive introduction of race may bring little benefit. The messy story behind the heart drug BiDil, approved by the FDA for African Americans, for example, makes it unconvincing as his poster child for race-based medicine.

Surfing the Exponential delves into the nascent field of synthetic biology, covering much the same ground as Specter's recent story in The New Yorker. This chapter is rich in technical detail on the promise of the technology, and to a lesser degree with the risks of making new, self-replicating life forms. Ultimately, though, Specter advocates "a new and genuinely natural environmental movement--one that doesn't fear what science can accomplish, but only what we might do to prevent it."

Such denialism is no more defensible for assessing risks than for judging benefits--both should to be analyzed thoroughly. Fear of the unknown is not always irrational.

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