November, 2007

I Reject Rousseau

Just two comments in reply to Linda. Read what I said about Rousseau with a calm eye. It says just the opposite of what you think you read: that we should NOT place supposed unwelcome consequences over the search for truth. I have never referred to Linda’s research as obnoxious and do not think […]

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Flynn, Ceci, and Turkheimer on Race and Intelligence: Opening Moves

William Saletan may be the first journalist to so directly acknowledge the scientific evidence suggesting a non-trivial genetic basis for racial differences in IQ (hereafter, the partly-genetic hypothesis) and to be allowed to publish his views. Publication of his 3-part article in Slate (Nov. 18-20, 2007) represents a stunning departure […]

Read: Flynn, Ceci, and Turkheimer on Race and Intelligence: Opening Moves

What Is the Alternative to Civil Discourse?

Our field is riddled with theoretical conundrums, but that is neither unique to our field nor does it imply that progress must await a total closing of the racial IQ gap. If research were to demonstrate that, for example, the racial gap in IQ has narrowed by .25 SD in the past few decades, and […]

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Arthur Jensen and John Stuart Mill

Before we abandon the topic of full discussion of race differences, everyone should read Mill’s classic, On Liberty. Mill warns us that governmental censorship is often not the main threat but rather the force of public opinion. He reviews the historical record and shows that all past restriction on open debate was counterproductive, […]

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Rational Discussion of the Offensive is Okay

Reviewing the contributions of Ceci and Turkheimer, I still agree with Ceci. For these reasons:
(1) What is offensive should not be discouraged as a subject for rational discussion. I do not doubt that discussion of group differences is offensive particularly to groups where the hypotheses reflect unfavorable stereotypes. Until recently anything that contradicted […]

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Race and IQ

The Theory of Innate Differences
Ceci and Flynn, while expressing their skepticism about the possibility of genetic differences between the races for IQ, agree that the question is a legitimate matter for scientific inquiry, to be settled by cool-headed evaluation of the empirical evidence. I disagree. I contend that:

The […]

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The Chilling Effect of IQ Taboos

William Saletan aptly summarizes the research on the genetic and environmental sources of variability in IQ scores. It’s refreshing to read someone so balanced on a topic where no one feels neutrally, and no one is dispassionate. Having said this, one can quibble with his take on some of the evidence. For example, the claim […]

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The Black-White IQ Gap

We aren’t the only ones discussing IQ right now. Over at Slate, William Saletan argues that the black-white IQ gap should not be a taboo subject and should be judged on the evidence. In this, he is entirely correct and I will be debating this issue with Charles Murray at the Manhattan Institute in […]

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Measuring Two Different Things: People and Trends

It is important to recognize that an instrument measures something aside from its own measurements and to be clear about what it is. Take the early thermometers. To say that heat was the readings they provided would be absurd. Heat was quite a separate thing, namely, what you felt on your skin on a warm […]

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The Significance of the Flynn Effect

Stephen J. Ceci, the Helen L. Carr Professor of Developmental Psychology at Cornell University, explains why Flynn’s work has been so important. According to Ceci, the received wisdom about the nature and effects of g, or general intelligence, led “some to argue that inequality in the distribution of wealth, prestige, and educational attainment is, in part, a consequence of unequal distribution of the intellectual capacity needed for high levels of functioning.” However, Ceci says, “[Flynn] has shown beyond doubt that general intelligence fluctuates systematically over time and this cannot be due to our having better genes than our grandparents,” and he goes on to explore the puzzles raised by this discovery.

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The Fundamental Intuition

University of Virginia psychologist Eric Turkheimer contests even James Flynn’s modest accommodation with the construct of g, or general intelligence. Turkheimer argues that the “fundamental intuition” of g is that “universal positive relations among mental tests compels a single dominant explanatory construct,” but that “the fundamental intuition is wrong.” According to Turkheimer, g is not “discovered,” but is simply posited as a convenience, like the Prime Meridian. g may be useful for some purposes, but a multidimensional explanation of ability may still be correct. “The trick is not to get hooked on any particular way of dividing up the pie,” Turkheimer writes, “because it is a short step from there to trying to find the Greenwich Meridian at the bottom of the North Atlantic.”

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Shattering Logic to Explain the Flynn Effect

Linda Gottfredson, co-director of the Delaware-Johns Hopkins Project for the Study of Intelligence and Society, defends the unity of general intelligence, or g, against Flynn’s attempt to “unravel g into its component parts” by charging that “his core argument rests on logical fallacies that profoundly misinterpret the evidence.”

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Shattering Intelligence: Implications for Education and Interventions

In this month’s lead essay, famed intelligence researcher James R. Flynn draws on his new book, What Is Intelligence? Beyond the Flynn Effect, to help answer some of the puzzles surrounding the controversial issue of IQ. Flynn, who first discovered that IQ scores were rising generation after generation, notes that this improvement has been more dramatic on some parts of IQ tests than on others, challenging ideas of a unified general intelligence or “g.” Flynn argues that the fact cognitive abilities do not develop together has important implications for education. Additionally, Flynn contends that the evidence for the co-determining reciprocal influence of brain and environment should lead us to set aside simple ideas about the primacy of nurture and nature in intelligence. Once we grasp that “the brain is much more like our muscles than we had thought,” we can do more to improve cognitive performance by doing more to exercise the brain.

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