Thanks to a reader for pointing out this Steve Pinker review of Malcolm Gladwell's latest collection in the Sunday Times. I had more or less stopped reading stuff on Gladwell, as the uncritical acceptance of many of his claims is just too depressing a reminder of the mediocrity of our commentariat.
An eclectic essayist is necessarily a dilettante, which is not in itself a bad thing. But Gladwell frequently holds forth about statistics and psychology, and his lack of technical grounding in these subjects can be jarring. He provides misleading definitions of “homology,” “saggital plane” and “power law” and quotes an expert speaking about an “igon value” (that’s eigenvalue, a basic concept in linear algebra). In the spirit of Gladwell, who likes to give portentous names to his aperçus, I will call this the Igon Value Problem: when a writer’s education on a topic consists in interviewing an expert, he is apt to offer generalizations that are banal, obtuse or flat wrong.
The common thread in Gladwell’s writing is a kind of populism, which seeks to undermine the ideals of talent, intelligence and analytical prowess in favor of luck, opportunity, experience and intuition. For an apolitical writer like Gladwell, this has the advantage of appealing both to the Horatio Alger right and to the egalitarian left. Unfortunately he wildly overstates his empirical case. It is simply not true that a quarterback’s rank in the draft is uncorrelated with his success in the pros, that cognitive skills don’t predict a teacher’s effectiveness, that intelligence scores are poorly related to job performance or (the major claim in “Outliers”) that above a minimum I.Q. of 120, higher intelligence does not bring greater intellectual achievements.
My opinion of Malcolm Gladwell was expressed here:
Malcolm Gladwell shows exquisite taste in the subjects he writes and talks about -- he has a nose for great topics. I just wish his logical and analytical capabilities were better ... My feeling is that Gladwell's work appeals most to people who can't quite understand what he is talking about.
What Pinker refers to as the major claim of Outliers: IQ above 120 doesn't matter, is easily shown to be false. Randomly selected eminent scientists have IQs much higher than 120 and also much higher than the average science PhD (120-130); math ability within the top percentile measured in childhood is predictive of future success in science and engineering; advanced education and a challenging career do not enhance adult IQs relative to childhood IQ.
So, accomplished scientists tend to have high IQs, and their IQs were already high before they became scientists -- the causality is clear. 10,000 hours of practice may be necessary but is certainly not sufficient to become a world class expert.
I recently remarked to a friend that many aspects of psychometrics which were well established by the 1950s now seem to have been completely forgotten due to political correctness. This leads to the jarring observation that recent social science articles (the kind that Gladwell is likely to cover) are sometimes completely wrong headed (even, contradicted by existing data of which the authors are unaware) whereas many 50 year old articles are clearly reasoned and correct. The data I cite in the links above comes from the Roe study of eminent scientists and the Terman longitudinal study of gifted individuals, both of which were conducted long ago, and the SMPY longitudinal study of mathematically precocious youth, which is ongoing. I've interacted with many social scientists whose worldview is inconsistent with the established results of these studies, of which they are unaware.