The increase in IQ from nutrition and education is going to experience stark diminishing returns, as has already been seen.
http://www.eric.ed.gov/ERICWebPortal/custom/portlets/recordD...
It's entirely possible that there is some factor of intelligence that is mostly inherited and that whites, blacks, Asians, etc., on average, possess equal amounts of this factor.
Is there some kind of competition I don't know about to mention the words "straw man" in as many threads as possible? It seems to pop up in just about every thread, along with the words "correlation does not equal causation".
I'd rather they point it out than let poor arguments pass for lack of language to describe it. Maybe we need new synonyms. Says something about the state of logical strength of many popular articles, doesn't it?
Yes, there are a number of lines of evidence that IQ is far from immutable at the individual level, even though environmental influences on IQ are very poorly understood. Because such environmental influences are poorly understood, it is not at all clear that societal increases in IQ can't continue.
I've enjoyed hearing from several well known psychologists about this, including some of the doyens of twin research, as I participate in the journal club in individual differences psychology and behavioral genetics
http://www.psych.umn.edu/courses/fall09/mcguem/psy8935/defau...
at the university where those researchers are based this fall semester. There is always lively discussion on what the data show, and what the data don't show. Thus far, there are no data to show a hard upper limit on how much individual academic achievement might raise with the best interventions, nor any predictable limit on how much secular increases in societal levels of IQ might continue.
A much more important argument is whether intelligence is immutable or not. What this article doesn’t do is look at the general intelligence factor – the correct way to measure intelligence. Attacking IQ is just a straw man – IQ isn’t the best measure of intelligence, the g-factor is. IQ tests are subject to boosting (i.e. increased performance by training).
The evidence that intelligence is innate is significant and mounting. The general intelligence factor is found in several studies to be immutable. It is possible to see the effects of the general intelligence factor by looking at fMRI when a person does a test. Intelligence has much more to do with physiology than anyone would like to admit.
It is sad that a lot of people would rather turn science into pseudo science than to acknowledge the fact. These views are subject to a very good book called “The blank slate: modern denial of human nature” (by Steven Pinker).
PS: James Flynn does not have any formal training in psychometrics. He is a political scientist and noted left wing New Zealand political activist. He is also author of “How to Defend Humane Ideals: Substitutes for Objectivity”.
I do not know why his views are continuously brought up when there are 100s of guys in the field that is better educated than him. It is unfortunate that when science and politics collides it is science that loses.
Studies get published if they survive peer review, and publications have citations. Citations, please?
I do not know why his views are continuously brought up when there are 100s of guys in the field that is better educated than him.
Because Flynn does his homework and makes unassailable research findings that are published in the best journals. Arthur Jensen has written, "Now and then I am asked . . . who, in my opinion, are the most respectable critics of my position on the race-IQ issue? The name James R. Flynn is by far the first that comes to mind." Arthur Jensen, "Differential Psychology: Towards Consensus" in Arthur Jensen: Consensus and Controversy, Sohan Modgil & Celia Modgil ed., p. 379 (1987). N. J. Mackintosh writes about the data Flynn found: "the data are surprising, demolish some long-cherished beliefs, and raise a number of other interesting issues along the way." Mackintosh, N. J. (1998). IQ and Human Intelligence. Oxford: Oxford University Press. Flynn grapples with the data, analyzes the data carefully, and engages in discussion with scholars from a wide variety of points of view about what the data mean. That's why Flynn's most recent book gains the praise
http://news.ycombinator.com/item?id=865429
already mentioned in another reply to this thread.
After edit:
Because I have Pinker's book at hand, I checked his chapter on the issue, and Pinker says, "The Third Law: A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families." The environment in the world at large does matter, and it matters for a lot. Pinker is forced to acknowledge this because that is what the research shows. It is regrettable that Pinker fails to cite the articles that establish the difference between heritability and mutability ("malleability") directly in the text of his book, but I will cite those here. There is a crucial issue here to be curious about, and that is exactly what a calculation of broad heritability definitely predicts. It predicts a lot less than what many readers unfamiliar with genetics might guess. It happens that some of the leading authors on human behavioral genetics just wrote an article about what heritability does and does not mean
Johnson, Wendy; Turkheimer, Eric; Gottesman, Irving I.; Bouchard Jr., Thomas (2009). Beyond Heritability: Twin Studies in Behavioral Research. Current Directions in Psychological Science, 18, 4, 217-220.
http://www.ingentaconnect.com/content/bpl/cdir/2009/00000018...
(one online abstract)
http://www3.interscience.wiley.com/journal/122587149/abstrac...
(the main link to the article)
Alas, a peek behind the pay wall that was available a little while ago when I posted this article here on HN
http://news.ycombinator.com/item?id=838534
is now dead. But I have the full text of the article at hand, as I am currently attending a weekly journal club with some of the authors, and one key paragraph from the article must be read by anyone who draws conclusions from heritablity figures:
"Moreover, even highly heritable traits can be strongly manipulated by the environment, so heritability has little if anything to do with controllability. For example, height is on the order of 90% heritable, yet North and South Koreans, who come from the same genetic background, presently differ in average height by a full 6 inches (Pak, 2004; Schwekendiek, 2008)."
This simply reemphasizes a point that is familiar to anyone who has studied genetics carefully, namely that the pre-Mendelian concept of heritability says nothing about malleability, the degree to which a trait can be influenced by environmental variables.
Angoff, W. H. (1988). The nature-nurture debate, aptitudes, and group differences. American Psychologist, 43, 713-720.
Mange, A. & Mange, E. J. (1990). Genetics: Human Aspects.
Kaufman, Alan S. (1990). Assessing Adolescent and Adult Intelligence.
So any statement in this thread that heritability somehow constrains the expression of g or of IQ is actually conceptually incorrect.
Test designers purport to do that, but it's a generally replicated research finding that increased exposure to schooling, cross-culturally and across different brands of IQ tests, improves IQ test scores. See
Ceci, Stephen J. (1991). How Much Does Schooling Influence General Intelligence and Its Cognitive Components? A Reassessment of the Evidence. Developmental Psychology 1991, Vol. 27, No. 5, 703-722
for one classic paper on this subject.
http://www.pressrun.net/weblog/2009/09/outliers-whats-rice-g...
I'm sure it has nothing to do with the fact that education has long been a cornerstone of Chinese society, going as far back as standardized tests during the Han dynasty.
Not been to the guido hood lately?
This essay doesn't attempt to accurately and fairly summarize opposing arguments.
"It is not just the fascinating effect that makes the book special. It's also Flynn's style. There's an unusual combination of clarity, wit, apposite allusion, and farsightedness in making connections and exploring unexpected consequences. The Flynn effect, in Flynn's hands, makes a good, gripping, puzzling, and not-quite-finished story..." --Ian Deary, Edinburgh University
"This book is a gold mine of pointers to interesting work, much of which was new to me. All of us who wrestle with the extraordinarily difficult questions about intelligence that Flynn discusses are in his debt.." --Charles Murray, American Enterprise Institute & co-author of The Bell Curve
"This highly engaging, and very readable, book takes forward the Dickens/Flynn model of intelligence in the form of asking yet more provocative questions. . . A most unusual book, one that holds the reader's attention and leaves behind concepts and ideas that force us to rethink all sorts of issues.." --Sir Michael Rutter, Kings College London
"Flynn provides the first satisfying explanation of the massive rise in IQ test scores. He avoids both the absurd conclusion that our great grandparents were all mentally retarded and the equally unsatisfactory suggestion that the rise has just been in performance on IQ tests without any wider implications.." --N. J. Mackintosh, University of Cambridge
"Citing many scholarly works, Flynn paints a dynamic picture of what intelligence is and the role of a person's genetic background, physiology and neurology, immediate environment and broader social factors...he has produced an impressively multidimensional and often wise look at the elusive topic of human intelligence." --Publisher's Weekly
"In What is Intelligence? James R. Flynn...suggests that we should not faciley equate IQ gains with intelligence gains. He says that it's necessary to 'dissect intelligence' into its component parts: 'solving mathematical problems, interpreteing the great works of literature, finding on the spot solutions, assimilating the scientific worldview, critical acumen and wisdom.' When this dissection is carried out, several paradoxes emerge, which Flynn in this engaging book attempts to reconcile." --Richard Restak, American Scholar
"The 20th century saw the "Flynn Effect" - massive gains in IQ from one generation to another." --Scientific American Mind
"In a brilliant interweaving of data and argument, Flynn calls into question fundamental assumptions about the nature of intelligence that have driven the field for the past century. There is something here for everyone to lose sleep over. His solution to the perplexing issues revolving around IQ gains over time will give the IQ Ayatollahs fits!." --S. J. Ceci, Cornell University
"What Is Intelligence? is one of the best books I have read on intelligence-ever...This is a brilliant book because, first, it helps resolve paradoxes that, in the past, seemed not to lend themselves to any sensible solutions...one of the best things about the book is Flynn's sense of humility...this is a masterful book that will influence thinking about intelligence for many years to come. It is one of those few books for which one can truly say that it is must reading for anyone." --Robert J. Sternberg, PsycCRITIQUES
"...In this thoughtful, well-written book, Flynn offers an account of why the so-called Flynn effect occurs and what it means (and does not mean)....This is the clearest, most engaging work on intelligence....All will learn from the author's nuanced arguments. Some may quibble with Flynn's observations, but their work is cut for them: one cannot fault his clarity or ingenuity. Essential." --D.S. Dunn, Moravian College, CHOICE
"...James Flynn is best known for having discovered a stubborn fact...he established that in every country where consistent IQ tests have been given to large numbers of people over time, scores have been rising as far back as the records go, in some cases to the early 20th century. What Is Intelligence? is Flynn's attempt to explain this phenomenon, now known as the Flynn effect... an important take on what we have made of ourselves over the past few centuries and might yet make of ourselves in the future." --Cosma Shalizi, Assistant Professor in the Statistics Department at Carnegie Mellon University and an external professor at the Santa Fe Institute, American Scientist
Link to description of the book (whence those reviews came):
http://www.amazon.com/What-Intelligence-Beyond-Flynn-Effect/...
An in-depth transcript of a lecture by the author:
http://www.psychometrics.sps.cam.ac.uk/page/109/beyond-the-f...
