Begley and the Grand Conclusion

Sharon Begley had a piece in Newsweek magazine about scientists rethinking positions. Begley is not the retiring sort, apparently:

Rare, however, are changes of mind by scientists identified with either side of a contentious issue. No one who rose to fame arguing that Alzheimer’s disease is caused by sticky brain plaques and who has now been convinced by evidence that the plaques are mostly innocent bystanders, not culprits. No one who once pushed hormone replacement therapy to prevent heart attacks in menopausal women who now realizes that the drugs increase the risk of heart attacks (as well as stroke and breast cancer). No one who cast his lot with the theory that a killer asteroid sent the dinosaurs into extinction who now reads the impact-crater evidence as implicating worldwide volcanism instead. But really, we shouldn’t be surprised. Proponents of a particular viewpoint, especially if their reputation is based on the accuracy of that viewpoint, cling to it like a shipwrecked man to flotsam. Studies that undermine that position, they say, are fatally flawed.

All this based upon the results of the 2008 “Edge” question, a remarkable achievement in meta-analysis on Begley’s part.

Was there anyone who “rose to fame” on the basis of advocating a particular mechanism for Alzheimer’s in the respondents to the 2008 Edge question? Not that I can see. Begley does not justify her sweeping conclusion in terms of the expected prior probability of scientists who are confronted with a major change in evidence in their field of study in their lifetime, modulated by average point in career of the correspondent. I guess Begley thinks that happens to everybody every other week, but that would be baseless speculation. A brief look at the respondent list demonstrates that it wasn’t just scientists contributing, as the presence of thespian Alan Alda exemplifies. Beatrice Golomb was a respondent to the Edge question, but she is on record as being skeptical of the benefits of proposed treatments based on the particular mechanism Begley disses. Golomb also is on the side of the angels concerning Begley’s next sentence about hormone replacement therapy, as her response to the Edge question is specifically on that topic and criticizes HRT advocates for sloppy experimental design. Begley’s next target is puzzling, because Scott Sampson’s essay in the collection discusses his change of mind because of the evidence between explanations for the KT boundary event that did in the dinosaurs — but he went the other way, dropping his preference for gradualist volcanism for the catastrophic impact explanation. Why Begley insists that only changes of mind in the other direction should count toward the good remains a mystery. Is Begley in command of facts not yet available to the researchers who are closest to the question? If so, she doesn’t divulge them here.

There certainly exist scientists who have long clung to favored pet theories long past when the weight of the evidence should have caused them to change their mind, with Louis Agassiz perhaps serving as the archetype. But Begley’s argument is not about an existence proof, but rather a hasty generalization supposedly applicable to the vast majority of the scientific profession. And that Begley has no basis for, not even within the limited sample of the Edge question results.

Maybe a question in the journalist profession could be the basis for changes of mind, too, specifically whether anything filling column-inches is better than a far more accurate void.