Tuesday, December 23, 2014

Ask Not for Whom the Bell Curves

Scott Alexander:

See for example this recent Xenosystems post about a Twitterer claiming The Bell Curve has been “well-refuted”. There are definitely a lot of people who have written books, articles, and papers arguing that The Bell Curve is wrong, often in very strong terms. There are also a lot of people who have written books, articles, and papers saying that the first set of books, articles, and papers are wrong and The Bell Curve is right, also in very strong terms. To say that the first set is a “refutation” or “debunking” is as basic a mistake as saying that the new rape study is a “refutation” or “debunking” of the earlier rape study.

(albeit a mistake likely to be made by exactly the opposite people)

There are certainly things that have been “well-refuted” and “debunked”. Andrew Wakefield’s study purporting to prove that vaccines cause autism is a pretty good example. But you will notice that it had multiple failed replications, journals published reports showing he falsified data, the study’s co-authors retracted their support, the journal it was published in retracted it and issued an apology, the General Medical Council convicted Wakefield of sixteen counts of misconduct, and Wakefield was stripped of his medical license and barred from practicing medicine ever again in the UK. The British Medical Journal, one of the best-respected medical journals in the world, published an editorial concluding:

Clear evidence of falsification of data should now close the door on this damaging vaccine scare...Who perpetrated this fraud? There is no doubt that it was Wakefield. Is it possible that he was wrong, but not dishonest: that he was so incompetent that he was unable to fairly describe the project, or to report even one of the 12 children’s cases accurately? No.

Meanwhile, The Bell Curve was lambasted in the popular press and by many academics. But it also got fifty of the top researchers in its field to sign a consensus statement saying it was pretty much right about everything and the people attacking it were biased and confused. Three years later, they re-issued their statement saying nothing had changed and more recent findings had only confirmed their opinion. The American Psychological Association launched a task force to settle the issue which stopped short of complete agreement but which given the circumstances was pretty darned supportive. There are certainly a lot of smart people with very strong negative opinions, but each one is still usually met by an equally ardent and credentialed proponent.

One of these two things has been “well-refuted”. The other has been “argued against”.

I've only been reading Alexander regularly for a few months. I don't know for sure what his politics are, but I have the impression he's basically liberal. He strikes me as being impressively dedicated to logical thinking and empirical fact-finding, and that, in addition to the obvious pains he takes to explain himself clearly and thoroughly, makes me trust his perspective unless given strong reasons not to. So, it could be that I just basically identify all those characteristics with being "liberal", and thus provisionally apply the label to him.

What makes this bit interesting to me is the fact that, assuming I'm right in my guess about his political outlook, this is the first time I've ever seen a liberal suggest that The Bell Curve was anything other than maliciously-motivated racist pseudoscience. I mean, I've been aware of the book for almost my entire adult life, and I have never once encountered anyone who wasn't, shall we say, predictably conservative, suggesting that the book's thesis may have been mostly accurate. Even Freddie deBoer and Andrew Sullivan, with whom I wholeheartedly agree that even dangerous, wrong ideas should be confronted openly and honestly, seem to take for granted that the book is clearly wrong. "True but largely irrelevant" doesn't seem to be an allowable option. If it's not declared "completely false and dangerously pernicious", there might be terrible consequences.

I haven't read the book, and even if I were interested, I'm not in a position to judge any of the impressively-credentialed authorities who take a stand one way or the other. True or false, I can't see how it would change the way I behave or think. My only point is that I find it somewhat scary that I, who like to think of myself as being fairly inquisitive and independent-minded, could have been living in a tightly-sealed liberal filter bubble for so long. How many things do I take for granted as being obviously true, not because I know, but because I've just never heard a reputable source say otherwise? How many arguments are not about the truth or falsity of the subject, but rather about the fear of what it might mean for the subject to be true or false? We like to think that the epistemological floor beneath our feet is solid stone, but we might look down to see that we're standing on a rickety rope bridge instead.