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How to Raise Our I.Q. (nytimes.com)
60 points by tokenadult on April 16, 2009 | hide | past | favorite | 57 comments



The most important part to me :

That’s particularly true of girls and math, apparently because some girls assume that they are genetically disadvantaged at numbers; deprived of an excuse for failure, they excel.

Our conditionment plays a very important role in limiting or improving our abilities. Doing maths is solving problems. During this process, having empowering believes about oneself is crucial.

I remember when I learned how to dance. The first thing I had to fight was my own belief that as a geek, I was good at maths but supposed to be akward at dancing. Not giving up is much difficult in this condition, but the reward is of a greater kind when you fight this particular demon. Believing in yourself is first and foremost refusing to let the outside world determine your idendity. Reality is complex and we are too multi dimensional to be fit in one category or another.

Instead of focusing on abilities, I prefer to focus on the center of interests of someone. Passion is the master, ability is the servant. While it's true we don't have the same potential in every area, we never know what we are capable of until we try it. And trying is precisely to challenge our inner beliefs, daring to face the unknown.


If you are looking for practical advice remember the big 4:

Diet: Specifically micro-nutrients and more generally a healthy diet.

Sleep: Vastly underrated, sleep deprivation is on par with getting drunk. Consider, long term sleep deprivation can kill you.

Mental Activity: Consider, Solitary confinement can quickly lead to long term mental issues.

Exercise: It's frighting how important this is.

PS: I suspect sleep and diet account for most of the differences in measured IQ in the french study.


I go to a fairly difficult school and I work 25+ hours a week at an internship. So routine is very important to me, a lot of time Diet, Sleep, and Exercise go to the wayside. It seems I will get a good routine going of eating well and exercising but then I go on break and I loose it.

Thanks for reminding me.


"If intelligence were deeply encoded in our genes, that would lead to the depressing conclusion that neither schooling nor antipoverty programs can accomplish much."

More optimistically, it means that they're already working pretty well. In a chaotic environment where smart people are likely to be randomly struck down, most variation in intelligence is environmental: The smartest are those who avoid malnutrition, neonatal infections, mothers with drug addictions, etc. In a utopia where everyone receives perfect education and lives up to their full innate potential, all variation is due to genetics, because we're holding everything else constant.

Edit: Less optimistically, it also means that there are no additional gains to be had at the margin. Maybe the benefit of public schooling has been just to sort smart-student pegs into high-paying-job holes, and now that most of that sorting is done there's nothing left for schools to do.


Another reply in this thread cites some of the research on IQ score trends over time. There probably is more gain yet to be had among disadvantaged populations than among advantaged populations (which have already enjoyed huge gains), but the mechanism of causation of IQ gains is unclear enough that there may yet be a lot of room for increase for all populations.

Even if IQ gains grind to a halt in particular places, there is still much to be done to raise the level of rationality in the population there. (Another reply to this thread just cited Keith Stanovich's recent book What Intelligence Tests Miss,

http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...

which is all about how to improve rationality among people of various IQ levels.) And for general social improvement, it is also possible to shape public policies so that they take into account common forms of human irrationality,

http://www.amazon.com/Nudge-Improving-Decisions-Health-Happi...

so that daily life is more sound even if the people living it are neither more intelligent nor more rational.


This doesn't really apply in the western world, but interestingly enough, one of the cheapest ways to raise an society's IQ is by introducing the use of iodized salt:

http://www.nytimes.com/2006/12/16/health/16iodine.html


I've often wondered how much diet plays a role in "mental acuity." When he referred to poor children being adopted into upper middle class families that was the first thing that came to mind.


It's a very big role, especially in early childhood. As the parent points out iodized salt is a big one, another is omega 3 oils.


Also useful is getting enough calories every day.


Omega-3 needs to be balanced against Omega-6, but there isn't agreement on the ratio. They're polyunsaturated fats, which I try to limit. But I aim for a 1:1 ratio.

Omega-3 is anti-inflammatory, the Omega-6 pro-inflammatory. They're both essential to bodily processes, even though O-6 is pro-inflammation.

Good sources of O-3: Fish Oil, Krill Oil, Salmon Oil


I read 1:6 (O-3:O-6) is supposedly balanced, no ill effect or positive effects. 1:4 is considered good, but aiming for a 1:1 is definitely a good target.

The thing I find most disturbing is that omega-6 can replace monounsaturated fats in your skin and could significantly increase your risk of cancer. I'm unsure of how exactly, but the polyunsaturated fats increase the free radical production, where as monounsaturated and saturated fats can prevent it. Not to mention polyunsaturated fats might inhibit vitamin D production.

Another thing to consider, omega-6 can inhibit your immune system, which further increases your risk of cancer. It just kicks you when you're down, not only can O-6 cause cancer, but it can stop your body fighting it too.


O-6s also down regulates thyroid function, decreasing metabolism.

http://wholehealthsource.blogspot.com/2008/12/omega-6-linole...

I didn't want to mention sat fat benefits, because I hate making heretical claims without time to back up them up, but I agree.

Even the AHA has admitted that stearic acid, a sat fat, is fine. As we turn up the power of the microscope on nutrition, sat fats suddenly aren't blanket bad for you. It looks like I depends on the form, source and context you're eating it. I try to down a lot of coconut milk/oil. It's a healthy sat fat, a MCT that's burned immediately instead of stored as fat.

The AHA promotes O-6s by the way. It seem like there's a lot of cached thought in nutrition. Many in the field can't design a study. They test a "high-fat diet" without thinking it matters what fats were eaten, and in what form.


Sodium is important to brain function. It's recently been linked with antidepressant properties:

http://www.scientificblogging.com/news_releases/salt_may_be_...


The easiest way to improve I.Q. scores is probably to take practice tests.


Really? I only ever thought of IQ as a measurement of elitism, not intelligence. I've met some really smart guys with IQs much lower than you'd expect, and dealt with some really stupid higher IQ folk.


As much fun as it is to decry high IQs as the sole purview of snotty brats who can't actually amount to anything in the real world, it is still nothing but a combination of sour grapes and a biased sample. You notice the brats, you don't notice the high-IQ people that aren't snotty brats.

Science says that A: IQ clearly doesn't measure "real intelligence" B: Whatever "real intelligence" is, IQ does correlate with it fairly highly (as well as a number of other measurements), though you must understand what "correlate" means to fully comprehend that and C: real intelligence has real impacts on your real life, no matter how wonderful or awful that may sound.

It's real. The science is strong. The science is much more complicated and nuanced than most people understand, or, more profound, than most people want to understand. If you want to really understand the world, dismissing IQ is not a good start. (Nor is putting it on a pedestal, of course. If you want to understand the real world, recognizing that there is ground in between is also pretty helpful.)


I'm going to discuss your comment in three parts. Thank god this isn't reddit as I'd probably follow up with a "Your shit's all fucked up and you talk like a fag" or a pun type post.

Your first assertion is that people who decry high IQs as the sole purviews of snotty brats is a combination of sour grapes and a biased sample. I can't speak based on a scientific sample of high IQ folk. I can only speak for myself and people I know. My IQ (in case you were wondering) is 167 according to SB5 testing (I was tested through most of my childhood and some of my early academic life) putting me in the fairly smart range. To provide a counterpoint, I'll quote Alfred Binet (the 'B' in SB5) and just say:

"The scale, properly speaking, does not permit the measure of intelligence, because intellectual qualities are not superposable, and therefore cannot be measured as linear surfaces are measured." - Binet 1905.

There are snotty brats with low IQs. There are snotty brats with high IQs. Thus we can surmise that in any given sample of sufficient size regardless of IQ there are snotty brats. If you don't believe me I suggest you visit 4chan.org sometime.

Your second comment tries to pair correlation with reality. In some cases this works, in your example it doesn't as "real intelligence" is undefined, yet we are expected to accept that this undefined and unmeasured form of intelligence correlates with IQ. If you were to define what constitutes real intelligence then there's a point of discussion, but you must admit that your statement 'Whatever "real intelligence" is' implies that you don't know what it is - to be honest no-one does and that's the problem. An IQ score doesn't provide a measure of real intelligence, only problem solving within a measured subset of boundaries.

This then acts as a counterpoint for your third argument being that:

The science cannot be strong if "real intelligence" is less definable than "Real Madrid". Therefore I pose the counterpoint that correlation of an individual's success rate of "Real Madrid" (whatever "success rate" is) is more valid than correlation with "Real intelligence".

After all, "Real Intelligence" never won La Liga, the European cup, and so on, yet noone would ever argue against the genius of Real Madrid's European cup winning squads, no more than you could argue with the master strokes of Van Gogh or Raphael, nor the abilities of Newton - despite his inferior understanding of modern mathematics and logic, nor the ancient greeks despite their limitations.

One of the things I really appreciate about HN is that people have constructive arguments and disagreements. I completely accept that there's an element of fun in the topic I discussed (particularly about football teams) but I would like to say that although I don't agree with you, thanks for expressing your opinion and challenging mine. It's always good to have to rethink your worldview :)


If you have a point in your discussion of my first point, it escapes me.

For your discussion of the second point and third point, let me tell you the term to Google: "g factor". You can take that argument up with psychologists themselves.

Your arguments against correlation are pretty much what I was trying to cover with my parenthetical. You aren't decrying correlation, you're decrying popular misapprehensions about correlation, ones which I don't share. The correlation is present and the statistical analysis is simple; nobody can point at the g factor in one single test, but the statistical tests that show it is there is Statistics 101-type stuff.

The science is clear. Take it up with the scientists. You can start by searching for "g factor". (I recommend the quotes be included.)


"In some cases this works, in your example it doesn't as 'real intelligence' is undefined, yet we are expected to accept that this undefined and unmeasured form of intelligence correlates with IQ."

So do you think (general) intelligence exists?


I've met some really smart guys with IQs much lower than you'd expect, and dealt with some really stupid higher IQ folk.

This accords with my experience after fifty years of life, but is not quite a proof that IQ is meaningless. IQ tests estimate a kind of abstract problem-solving ability useful for many real-world tasks, and correlated with life success in various occupations. But IQ is not the same as rationality,

http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...

http://www.amazon.com/What-Intelligence-Tests-Miss-Psycholog...

or, if you prefer this terminology, IQ is not the same thing as wisdom,

http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=978...

http://www.amazon.com/What-Intelligence-Beyond-Flynn-Effect/...

so it shouldn't be terribly surprising to see irrational or unwise behavior from high-IQ individuals, as I certainly have.


Publisher's description page for the book under review:

http://www.wwnorton.com/catalog/winter09/006505.htm


Yet while this view of I.Q. as overwhelmingly inherited has been widely held

He needs this straw man for the article to work at all. In fact, the belief that IQ is "overwhelmingly inherited" is considered socially repugnant, and has been for some time. All of the things he lists are just duplicates or variations on things we've already been doing, and mostly failing at.


socially repugnant has nothing to do with science. the data says parent IQ is highly correlated with offspring IQ.


Is the correlation more father --> son than father -->daughter? Is there a mean effect between parents? Which sex is the most dominant in passing along this trait? Are there any instances of the child having a greater than the average or either parent? That would be very interesting data.


Are there any instances of the child having a greater than the average or either parent?

There are many such instances. And there are instances of children having lower IQ scores than either parent.

More important, it is a rare case when the same individual has the same IQ score over the course of life. IQ can change over the course of life quite a lot. And any two brands of IQ test will not agree entirely in how they sort a group of test-takers into a rank order. And IQ scores don't tell the whole story about all the meaningful mental abilities that a learner has, as Lewis Terman (the first developer of IQ tests in the United States) was very honest about pointing out:

"There are, however, certain characteristics of age scores with which the reader should be familiar. For one thing, it is necessary to bear in mind that the true mental age as we have used it refers to the mental age on a particular intelligence test. A subject's mental age in this sense may not coincide with the age score he would make in tests of musical ability, mechanical ability, social adjustment, etc. A subject has, strictly speaking, a number of mental ages; we are here concerned only with that which depends on the abilities tested by the new Stanford-Binet scales."

(Terman & Merrill 1937, p. 25)


And the offspring are, expect in the case of adoption, in the same socioeconomic class as the parents.


The operative phrase being "except in the case of adoption."

http://en.wikipedia.org/wiki/Minnesota_Twin_Family_Study#The...


I certainly hope that somebody publishes any adoption studies of twins several decades ago and several other studies replicate the results, so we'll know if you made a relevant point.


doing a regression analysis shows that while socioeconomic factors obviously play a role, they do not account for all, or even the majority, of the difference.


Twin studies show that identical twins reared apart are highly similar in terms of (for example) IQ. Much more so than fraternal twins reared together (or apart for that matter)

This indicates that genetics certainly play a very important role here. It might not be PC to say so but the science is pretty clear.


the science is pretty clear

Actually, the science of broad heritability, which is what you are talking about here, is anything but clear. The concept of heritability (it originated with Francis Galton) is a pre-Mendelian concept, an example of the saying that a person with a hammer treats any problem as a nail.

Heritability says NOTHING about malleability of a particular trait in populations, as any professionally edited genetics textbook will remind you. And there is already plenty of empirical evidence that IQ scores, and real-world intelligent behavior outside the testing room, and rationality (which is distinct from IQ) are exquisitely sensitive to environmental influences, many of those influences being cultural or educational rather than nutritional. That's what the book under review is about: providing a large number of citations to primary research literature on the malleability of IQ and educational achievement.


data says parent IQ is highly correlated with offspring IQ

What's the significance of that in relation to the book review submitted here?


That a better way to raise average IQ is to encourage smart people to breed?


a better way to raise average IQ is to encourage smart people to breed?

That's an interesting hypothesis, but the effect size of environmental changes is MUCH larger than the effect size of changing gene frequencies in increasing the IQ scores of the general population. It has been typical for decades for authors who take a strongly hereditarian (which means "pre-Mendelian," really) view of influences on IQ to suppose that IQ score trends over time would be for the population mean to decline. In fact, population trends over time in countries all over the world have been HUGE increases in IQ.

The Stanford University researchers who developed the first few versions of the Stanford-Binet IQ tests had access to data for decades that could have revealed a surprising trend in raw item content performance on IQ tests. The trend, now known as the Flynn Effect, after Professor James R. Flynn, who had the greatest role in discovering it, is that raw scores on IQ tests, including all kinds of IQ tests loaded on fluid intelligence, have risen over time in national populations all over the world.

James R. Flynn started slowly but worked steadily in finding data sets and eventually found a large body of tests for which raw score data is available over long time series. His first published paper (1984) on the issue of IQ score changes over time was based on the renorming of the most commonly used IQ tests in the United States. He found that as new editions of the major IQ tests (the Wechsler test and the Stanford-Binet) were published, that the newer edition of each test invariably had a norming sample population that did better on the old edition's item content than had the old edition's original norming sample population. In other words, for a given brand of IQ test, as time went on, the average person did better and better on the raw item content of that test, resulting in higher and higher IQ scores over time for people tested on the same test with score calculation based on the earliest norms.

The possibility that raw scores on IQ tests were rising so consistently, and in such magnitude, was so surprising that it prompted many psychologists to cast doubt on the sample populations used for the early studies that showed this phenomenon--even though those sample populations were none other than the norming sample populations for the major brands of IQ tests. Psychologist Arthur Jensen proposed to James R. Flynn in January 1983, while Flynn's first major article on score trends was awaiting publication, that a good data set to show changes in IQ scores over time should

a) be comprehensive, e.g., a test of an entire national population, to eliminate the possibility of sample bias,

b) use the same test from generation to generation, with time trends shown by raw score differences,

c) emphasize "culture fair" tests such as Raven Progressive Matrices, which were presumed then not to include item content that is taught by compulsory schooling,

d) be based on adult populations, who have reached a mature level of intellectual functioning, to minimize the effect of differing rates of intellectual growth in childhood from one generation to the next.

Amazingly, Flynn found data sets with all of those characteristics, especially data sets from compulsory IQ testing of NATO draftees in the Netherlands, Belgium, and Norway. The data based on a subset of items from the Raven Progressive Matrices test showed substantial raw score rises for Dutch draftees: if the 1952 population mean is taken to be IQ 100, by 1982 the Dutch male mean IQ was 121. The IQ raw score rise over time was smooth, and by the end of this period had resulted in ceiling effects on the test for a significant number of draftees (Flynn 1987). Flynn has suggested an experimental design that might help unravel the causes of the increase in raw IQ scores over time, while reviewing newly discovered data sets that extend observation of IQ score rises backward in time to the beginning of IQ testing. The Raven test, early in its use, was given to an age cohort born in the 1870s as part of a study of IQ changes over the course of adult aging. Careful analysis of this cohort allows extending IQ raw score trends back to the beginning of IQ testing, showing that fully 90 percent of Britons born in 1877 scored below the fifth percentile of Britons born in 1967, or in other words that most turn-of-the-last century Britons had an IQ of 75 or lower on a highly g-loaded IQ test, according to current norms (Flynn 1999; Flynn 2000b).

As Mackintosh (1998, p. 104) 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."

CITATIONS:

Flynn, James R. (1984). The Mean IQ of Americans: Massive Gains 1932 to 1978. Psychological Bulletin vol. 95, pages 29-51.

Flynn, James R. (1987). Massive IQ Gains in 14 Nations: What IQ Tests Really Measure. Psychological Bulletin, vol. 101, no. 2, pages 171-191.

Flynn, James R. (1998). IQ Gains over Time: Toward Finding the Causes. In Neisser, Ulric (Ed.). The Rising Curve: Long-Term Gains in IQ and Related Measures. Washington, DC: American Psychological Association.

Flynn, James R. (1999). Searching for Justice: The Discovery of IQ Gains over Time. American Psychologist, vol. 54, No. 1, pages 5-20.

Flynn, James R. (2000a). IQ Gains, WISC Subtests and Fluid g: g Theory and the Relevance of Spearman's Hypothesis to Race. In Gregory Bock, Jamie Goode & Kate Webb (Eds.), The Nature of Intelligence (Novartis Foundation Symposium 233) (pp. 202-227). Chichester, United Kingdom: Wiley.

Flynn, James R. (2000b). IQ Trends over Time: Intelligence, Race, and Meritocracy. In Kenneth Arrow, Samuel Bowles & Steven Durlauf (Eds.). Meritocracy and Economic Inequality (pp. 35-60). Princeton: Princeton University Press.

Mackintosh, N. J. (1998). IQ and Human Intelligence. Oxford: Oxford University Press.


If the Flynn effect was true, then our great-grand parents must have had average IQs that would have categorized them as mentally disabled today. Clearly, this was not the case. My grand parents in their prime were just as smart as my parents, and my parents and uncles are just as smart as my cousins.

It's also interesting that measures of vocabulary and numeracy have been flat over the past century. More evidence that cognitive abilities have been flat.

emphasize "culture fair" tests such as Raven Progressive Matrices, which were presumed then not to include item content that is taught by compulsory schooling,

Here is the problem. Doing a Raven Progressive Matrix is just as much a learned skill as math or vocabulary. If people went from learning no math in 1900, to learning lots of math in 2000, scores on math tests would go up, even without any gains in underlying cognitive abilities.

All the Flynn effect means is that people have much more exposure to the type of puzzles in the Raven Progressive Matrix today than they did in the 1950's. Numeracy and vocab are actually better measures of historical trends in IQ, because environmental exposure has been more constant between the two time periods.

When people try and measure intelligence, they are trying to measure the underlying cognitive abilities that allow people to learn faster and achieve higher levels of cognitive skills. Unfortunately, there is simply no way to measure this directly. The only way to measure it, is to give a person a skill test, and then control for environment. This will always be fraught with potential for error.


My grand parents in their prime were just as smart as my parents, and my parents and uncles are just as smart as my cousins.

And this is one of the best empirical proofs that IQ scores are not a "measure" of how smart someone is. James Flynn discusses exactly this point of yours in several of his writings. He relates a story from Arthur Jensen about a mentally retarded man who claimed to be baseball fan, but who was very vague about the rules of baseball and didn't seem to know the names of many professional players. Yet that man had an IQ score that would relate back in time to a population average score from the era when baseball became a popular sport, widely followed in the United States.

All the Flynn effect means is that people have much more exposure to the type of puzzles in the Raven Progressive Matrix today than they did in the 1950's.

I'm very sympathetic to this statement, because I used to think that it offered the best explanation for the Flynn effect. But I am now convinced by Flynn's latest book

http://www.amazon.com/What-Intelligence-Beyond-Flynn-Effect/...

that on the one hand the gains in IQ test scores are real, and not just artifacts of familiarity with test item content (in large part because so many different kinds of tests have all shown this effect) and on the other hand that IQ has increased in society, and has been applied in the labor market and other aspects of daily life, without wisdom (Flynn's term) or rationality (Stanovich's) term increasing as generally in society.

You'd probably enjoy reading Mackintosh's book,

http://www.amazon.com/IQ-Human-Intelligence-N-Mackintosh/dp/...

by far the best introductory text on IQ testing, and Flynn's latest

http://www.amazon.com/What-Intelligence-Beyond-Flynn-Effect/...

to delight your mind by grappling with how some specialist researchers have attempted to resolve the interesting issues you bring up in your reply.


I haven't read the books you've mentioned, although I'm pretty familiar with the debate, and the latest arguments.

I think it's interesting to make an analogy with a sport like running. If you measure running ability in a group where every person has absolutely no training, all the differential in running ability will be genetic. But a person will be able to train and improve, and so a change in environment ran result in gains in ability. If some people in the group start to train harder, then the differential in scores will be a mix of environmental and genetic.

If you compare members of a cross country team who all endure the same grueling training, the differences in their running speeds will be genetic. If one member tries to train even harder, he will probably be unable to raise his speed even higher. At some point, he maxes out and no training will raise his speed even further.

The subtests that have a flat trend were vocab, math, and general knowledge. What this indicates is that the environment of a century ago maxed people out at these skills a century ago. This is not surprising, as these skills are the most culturally common skills. Even in 1900 a person had constant exposure to reading, math, and general knowledge.

The subtests that have seen the greatest rise are all obscure skills - object assembly, picture arrangement, similarities. My guess is that the great increase in schooling resulted in more training in these obscure skills. Increased availability of games and puzzle books also helped. In 1900 if you were a genius kid, you read the classics. In 2009 you can play all sorts of fun puzzle games online or in books. As a result of this, scores on these obscure puzzles have gone up.

The net of this may mean that the hardcore hereditarians ( Murray, Jensen) are wrong about the specifics but right about the big picture. They are wrong to think that differences in the Raven test by themselves mean that one group has more natural cognitive abilities than another group. But they are probably right that individual and group differences in the economically and socially useful cognitive skills are mostly genetic. The differences in the obscure cognitive skills ( Raven's, picture arrangement) may be much more environmental.


I suspect that the Flynn effect begins and ends with the improvement to diet, as is the case with height. Though really, society has changed in so many ways in 100 years, that it's impossible to say this or that was responsible, therefore let's replicate it. At any rate, there's a serious upper limit to it.

http://en.wikipedia.org/wiki/Flynn_effect#Has_progression_en...


I suspect that the Flynn effect begins and ends with the improvement to diet

Flynn points to data from a World War II famine in the occupied Netherlands showing that the famine region had no difference in IQ changes over time from the region that didn't experience famine. The IQ score increase has also occurred in countries that were well nourished to begin with for the most part.


the flynn effect has leveled off and shows signs of starting to reverse in industrialized nations.


I'll accept "leveled off" regarding certain countries, having read Flynn's work, and I'll accept "starting to reverse" if you are only talking about crystallized intelligence, for the same reason, but do you have any current citations to a disfavorable trend anywhere in fluid intelligence?


I'm looking for a copy of the paper that doesn't require access to a university archive. Every link so far goes to the same source. the name of the paper if you want to look for it is

A long-term rise and recent decline in intelligence test performance: The Flynn Effect in revers


Also, from mynameishere's Wikipedia reference:

"The end of the Flynn effect?: A study of secular trends in mean intelligence test scores of Norwegian conscripts during half a century"

http://dx.doi.org/10.1016%2Fj.intell.2004.06.004

After all, this makes sense. Flynn effect seems to be working mostly by reducing "bad stuff" going on that would make you dumber than your potential (most of the gains are concentrated in the lower half of the distribution and negligible in the top half).

Once everybody's environment is more or less ok, there is no magic that will start to produce geniuses from normal people.


There was a comment on iSteve, where someone said that perhaps whites were not intrinsically smarter than the global average (of about 90) but, that they've had a headstart of a century of Flynn Effect.


this is an actual possibility, watching the flynn effect in devloping vs industrialized nations is what led to the idea (AFAIK) there's not enough data to be able to draw any conclusions, partly due to the stigma of intelligence research.



We had almost this exact same discussion a month ago. Firstly, you quote only from Flynn and not from any scientist holding an opposing viewpoint (e.g. Arthur Jensen). Although Flynn is a good scientist, I don't think that it is good to rely just on the studies of one political scientists and activist – he is author of “How to Defend Humane Ideals: Substitutes for Objectivity” after all).

There are numerous studies that also show that the general intelligence factor is due to physiological effects (e.g. size of different areas of the brain, etc...). How do you explain that?

There is a theory on why when people are trained in a task they do better – it turns out that the amount of “general intelligence” used is less. There are also studies that show this effect with PET scans of the brain:

> Thus, the largest GMR decreases with practice were found on subtests with the highest g loadings. Jensen noted this finding was consistent with what he termed the conservation of g. Namely, with practice and training, tasks become more automatized and require less g.

(from Haier [1])

There is a recent study (2008, te Nijenhuis ,van Vianen , van der Flier [2]) that shows that the increase in RSPM and other scores is because of training and is not an increase in the overall general intelligence [2] (the studies that you cited is all 8 years or older). Incidentally this study cites two of the Flynn papers that you cited (Massive IQ Gains in 14 Nations: What IQ Tests Really Measure, IQ Gains, WISC Subtests and Fluid g: g Theory and the Relevance of Spearman's Hypothesis to Race).

The idea that Flynn proposes (i.e. that general intelligence is increased over time is dismissed). Here is a full quote of the abstract of the paper (if you need the full paper and do not have access to it, msg. me and I will email it for you):

IQ scores provide the best general predictor of success in education, job training, and work. However, there are many ways in which IQ scores can be increased, for instance by means of retesting or participation in learning potential training programs. What is the nature of these score gains? Jensen [Jensen, A.R. (1998a). The g factor: The science of mental ability. London: Praeger] argued that the effects of cognitive interventions on abilities can be explained in terms of Carroll's three-stratum hierarchical factor model. We tested his hypothesis using test–retest data from various Dutch, British, and American IQ test batteries combined into a meta-analysis and learning potential data from South Africa using Raven's Progressive Matrices. The meta-analysis of 64 test–retest studies using IQ batteries (total N = 26,990) yielded a correlation between g loadings and score gains of − 1.00, meaning there is no g saturation in score gains. The learning potential study showed that: (1) the correlation between score gains and the g loadedness of item scores is − .39, (2) the g loadedness of item scores decreases after a mediated intervention training, and (3) low-g participants increased their scores more than high-g participants. So, our results support Jensen's hypothesis. The generalizability of test scores resides predominantly in the g component, while the test-specific ability component and the narrow ability component are virtually non-generalizable. As the score gains are not related to g, the generalizable g component decreases and, as it is not unlikely that the training itself is not g-loaded, it is easy to understand why the score gains did not generalize to scores on other cognitive tests and to g-loaded external criteria.

So what we have for the immutability of general intelligence is a theory, intelligence test results confirming the theory and PET scans of the brain showing this effect.

[1] Richard J. Haier, Ph.D., Positron Emission Tomography Studies of Intelligence: From Psychometrics to Neurobiology

[2] Jan te Nijenhuis , Annelies E.M. van Vianen , Henk van der Flier, Score gains on g-loaded tests: No g

PS: This reply is a little long so sorry for that.


I've read more of what Haier has to say since his name last came up in an HN thread. I especially like this quote:

"Just because intelligence is strongly genetic, that doesn't mean it cannot be improved. 'It's just the opposite,' says Richard Haier, of the University of California, Irvine, who works with Thompson. 'If it's genetic, it's biochemical, and we have all kinds of ways of influencing biochemistry.'"

http://www.newscientist.com/article/mg20126993.300-highspeed...

The all kinds of ways to influence biochemistry include influences that are not themselves biochemical. Things that people DO can cause biochemical changes in their brains. (Sleep deprivation is well known to do that, for example, as are activities that bring about good mood.) Very likely engaging in challenging education brings about biochemical changes that result in changes in IQ.

you quote only from Flynn and not from any scientist holding an opposing viewpoint (e.g. Arthur Jensen)

First of all, let me say very forthrightly that maybe mainstream journalism operates on an equal-time principle, but science manifestly does not. It actually makes no difference at all who says anything in science, because it should be examination of the data that leads to a conclusion, not examination of a scientist's reputation. But since you asked me to quote Arthur Jensen, I will be glad to:

"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." Modgil, Sohan & Modgil, Celia (Eds.) (1987) Arthur Jensen: Concensus and Controversy New York: Falmer.


> 'It's just the opposite,' says Richard Haier, of the University of California, Irvine, who works with Thompson. 'If it's genetic, it's biochemical, and we have all kinds of ways of influencing biochemistry.'"

There is good evidence that several compounds can increase intelligence (albeit temporary in most cases). A good example is several stimulants. The best way would probably be to alter the genetics directly. This however does not take away the fact that it is still innate and most people are not likely to see their intelligence changed.

> Very likely engaging in challenging education brings about biochemical changes that result in changes in IQ.

Is there any evidence that this is the case (i.e. research studies)? This may happen – but I have not seen any documented evidence of that this is the case.

If this was the case, children adopted at birth in middle class families would have general intelligence factors matching their step-parents (this is not the case). Also, the general intelligence factor would be changed with learning – but there has not been any evidence that this is the case.

> First of all, let me say very forthrightly that maybe mainstream journalism operates on an equal-time principle, but science manifestly does not.

That is true. Views of science with which the majority of scientists agree is generally represented as the opposite in the public press. A good reason for that is in the public sphere the “ought to” become “is” and scientists reinforcing that is given publicity.

There are several books like that (a lot of them by Gould).

> It actually makes no difference at all who says anything in science, because it should be examination of the data that leads to a conclusion, not examination of a scientist's reputation.

This is not entirely true. I am the last person to say a dissenting scientists should be silenced but the public simply cannot go into detail in any of several subjects. A good example is client change – no single person in the public is smart enough to know all facets of climate change science.

The public view is largely made up of the consensus view of a lot of scientists – but that does not mean that there is no place for the Bjorn Lomburgs.

The intelligence debate is the same – we should not rely on a single scientist. No single scientist is a master of all the fields (from neurobiology to psychometrics).

It is unfortunate that the politically correct view (the “ought to”) is promoted over the actual science. Public press is not representative in what goes on in the research.

> “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." Modgil, Sohan & Modgil,

That is true – and Jensen is correct in that. Flynn is in many cases the most prominent proponent of many views. My problem with Flynn is twofold.

The first problem is that he is a political scientists and he tries to defend the “ought to” - instead of trying to search for the “is”. If he was just active in intelligence research (instead of politics) it would be fine.

The second problem is that several scientists near the intelligence debate is viscously attacked for where they get their funding (in a politically motivated attempt to cut of funding). Their scientific objectivity was questioned and it is really ugly. Flynn is active in politics – yet no one attacks his scientific objectivity. It is a double standard that is simply not right.


no one attacks his [Flynn's] scientific objectivity

Yes, because he has demonstrated his scientific objectivity by changing his point of view from time to time, digging up new evidence when scientists say his previously offered evidence is inadequate, and scrupulously honoring his most ardent opponents with credit when their counterarguments prompt him to reconsider his previous publications. What Flynn writes in the early twenty-first century about IQ is much better quality research than what he wrote in the 1970s. (It's important to point out that already by the 1980s he was being published in Psychological Bulletin, the most prestigious journal in psychology, because his articles were meeting a high standard of scholarship.) Take a look at which psychologists and sociologists praise Flynn, his research in general, or his latest book on the Amazon.com page for his latest book:

Ian Deary, Edinburgh University

Charles Murray, American Enterprise Institute & co-author of The Bell Curve

Sir Michael Rutter, Kings College London

N. J. Mackintosh, University of Cambridge

Richard Restak, American Scholar

S. J. Ceci, Cornell University

Robert J. Sternberg, PsycCRITIQUES

and others.


> Yes, because he has demonstrated his scientific objectivity by changing his point of view from time to time, digging up new evidence when scientists say his previously offered evidence is inadequate, and scrupulously honoring his most ardent opponents with credit when their counterarguments prompt him to reconsider his previous publications.

This is true for Jensen and several other researchers - yet they are treated as pariahs in the public arena.

Several have questioned the objectivity of Jensen (and other researchers). As I have said before, James Flynn is both a passionate left-wing politician and he freely admits that he is egalitarian. E.g. in “How to defend Humane Ideals: Substitutes for objectivity”:

> This book was written by someone committed to humane-egalitarian ideals...

So, how can anyone question Jensen's objectivity but not that of Flynn?

There are several attacks on Jensen and others holding up Flynn as the poster boy (see at the end). Flynn has not done anything to dispel that. He even wrote a book attacking Jensen indirectly (Race, IQ and Jensen). Here is a quote:

> However, the last stand of the racist is not without importance, something I will attempt to demonstrate by giving a racist ideologue his say.

Scientists should search for truth – with not prior preconceptions or beliefs (i.e. he should search for truth and not just justification).

Here is an example of some Jensen attacks:

“Resurrecting Racism: The modern attack on black people using phony science” (by the popular anthropologist Francisco Gil-White):

You can read chapter 6 here : http://www.hirhome.com/rr/rrchap6.htm

I will not quote it since the whole chapter is full of Jensen attacks.

The extremely popular “The Mismeasure of Man” by Stephen Jay Gould also have the same attacks Jensen and others.

The list goes on. There is a saying that I translated to English: “They are not sheared over the same comb” i.e. Flynn are treated differently than those with opposing viewpoints.


It actually makes no difference at all who says anything in science

We aren't talking about physics where the variables are defined precisely. We are talking about psychology which is a pseudo-science at best as there are so many components that one may not really know what caused what or if it was something else that caused it. So when it comes to pseudo-science, a place where research is mosaic with many studies supporting the hypothesis and many others not, there is plenty of room for authors bias.

As for the debate of nature v nurture you to are having, one of you summed it up pretty well, the environment causes changes in the brain, but the question is a bit circular, namely did the brain make the person seek out the environment which led to the changes of the brain, or was the environment unrelated to the agents intentions. Anyhow, the question is not which one it is, but to what extend does nurture or nature influence. So its proportionality not absolutism.


"How do you raise your IQ? For some, standing on a soap box is the only way."


Wait, is IQ important or not?


IQ is very important, or at least intelligence is and IQ is the best way we have of trying to measure it. The Bell Curve is a pretty interesting book and it talks about all the things that IQ is correlated with.


I think he was being sarcastic/rhetorical.


while I.Q. doesn’t measure pure intellect — we’re not certain exactly what it does measure

It measures what it is set to measure. An IQ test given to school children measures their mastery of school subjects, and IQ test given to cadets measures their courage, quick thinking and whatever other skill is necessary to be a good cadet. So an IQ test is simply a test of certain skills and knowledge not intelligence as such.

That might explain why IQ has risen, since education is becoming more sophisticated, more are going to university, more people have access to information i.e. through internet, so too the skills and knowledge which is tested gives higher results.

That might also explain the adoption studies, the children in poor households have poor environment, i.e. no books and poor stimulation, i.e. parents don't engage them in conversations. So their knowledge suffers because they are expected to watch telly rather than play or read.




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