Wednesday, February 15, 2012

The Flynn Effect's Unseen Hand

[Edit 02/11/2017: The final version of this essay can be found here.]

The Flynn Effect's Unseen Hand

An Environmental Description of Human Intelligence

Abstract. The Flynn effect is a well known but inadequately explained phenomenon. Many different causes have been suggested for the population-wide generational increases in raw intelligence scores—including heterosis, better nutrition, more abundant education, environmental complexity and various combinations of the above—but none of these explanations have proven to be scientifically or logically compelling. This lack of progress could be pointing to a misunderstanding of human intelligence itself, which is depicted these days almost entirely in terms of brain-based functioning alone. This brain-based focus, however, has been precisely the bedevilment in the many explanations of the Flynn effect, for it has been difficult to reconcile neuronal mechanisms producing individual intelligence differences with neuronal mechanisms producing widespread intelligence gains. Accordingly, this paper proposes an alternative model of human intelligence, one not centered on the human brain. This model will highlight two complementary aspects of human intelligence: 1. environmental intelligence, defined as the total amount of non-biological pattern, structure and form contained within the human environment, and 2. individual intelligence, defined as an individual’s capacity to absorb and respond to environmental intelligence. It can be shown that it is environmental intelligence that serves as the sole driver of the Flynn effect, independently of individual intelligence, and along the way it will be demonstrated how environmental intelligence is similar to but far more comprehensive than the concept known as environmental complexity. It will also be demonstrated that this dual-aspect model of human intelligence effectively answers several of the Flynn effect paradoxes enumerated by James Flynn himself.

Introduction. Generational gains in raw intelligence scores were first noticed by several individuals—including Reed Tuddenham and Richard Lynn—but it was James Flynn in the 1980s who most clearly demonstrated the ubiquitous nature of what has come to be known as the Flynn effect. In the quarter century since, the Flynn effect has attracted a good deal of study and ink—in part because the phenomenon has been regarded as surprising, and in part because the phenomenon has continued to defy adequate explanation.

This situation stands in contrast to many other areas of intelligence research, including investigations into the source and impact of individual and group intelligence differences. Using factor analysis, identical twin studies and many other tools of modern cognitive science, researchers have been able to demonstrate consistently that individual intelligence differences produce significant impact in such areas as academics and career, and that these individual differences are driven mostly by genetics and are almost certainly neuronally based. These discoveries and achievements have led to a nearly unanimous consensus that intelligence is to be regarded exclusively as a brain-produced activity—in short, greater intelligence is spawned by a more effective brain.

The Flynn effect, however, throws something of a monkey wrench into this widely accepted view. To accept the conclusion that intelligence is exclusively a brain-produced activity—an activity determined primarily by genetics—one also has to anticipate that overall human intelligence will remain relatively stable across time, in accordance with standard biological and evolutionary principles. That is why the Flynn effect has been regarded as so surprising. The sizable raw intelligence gains recorded across the entire twentieth century far outstrip any plausible, brain-based advancement that might be anticipated under a biological, neuronal, or evolutionary framework.

One response to this dilemma would be to search for an orthogonal influence underlying the Flynn effect, and James Flynn himself (1999) has uttered that very reaction in almost those exact same terms (“it is as if some unseen hand is propelling scores upward”). In addition, Richard Lewontin’s (1976) parable of the seed corn provides a nearly precise description of how such an orthogonal influence would actually work. And yet no one has managed to follow this line of reasoning to its ultimate conclusion. What prevents further advancement is the widespread certainty that intelligence is strictly a brain-produced event. All the offered explanations for the Flynn effect—be they heterosis, better nutrition, advancing education, environmental complexity, or any combination or alternative to the above—all explanations are brought back eventually to human neurology, all are ultimately depicted as inducing material impact upon the human brain. This depiction is of course made mandatory by the dogma that intelligence arises exclusively out of human neurons. Vigor, nutrients, schooling, video games—all must somehow change the human brain, must make it more effective, make it more intelligent. Unfortunately, this circling back to neurology serves only to re-create the original tension: now there are neural mechanisms explaining individual intelligence differences and there are other neural mechanisms explaining population-wide intelligence gains, and yet somehow these mechanisms are supposed to co-exist within the same human brain and not interfere with the intelligence-producing impact of the other. Plausibility once again rears its ugly head.

A more decisive alternative would be to drop the dogma altogether. Nothing actually compels acceptance of the idea that intelligence is strictly a brain-produced phenomenon. Despite the consensus, no one has yet to demonstrate an actual neural mechanism producing an actual intelligence effect. Neural activity certainly accompanies intelligence behavior—there is plenty of evidence for that—but as scientists are wont to caution, correlation is not the same thing as causation. Furthermore, with the Flynn effect still a puzzle and a mystery, bumping against many of the fundamental assumptions regarding intelligence, it would seem there is adequate motivation for casting the cognitive net a little wider.

This paper will describe a model of human intelligence that removes the center of intelligence away from the human brain and places it more firmly within the human environment, a concept dubbed as environmental intelligence. Thus freed from the constraints of biology, neurology and evolution, human intelligence can be seen as able to change and accumulate at a significant rate, which indeed it must if it is going to produce the phenomenon known as the Flynn effect. The human brain still gets to play a role within this new model—under a concept dubbed as individual intelligence—but this role will be described as secondary. Instead of producing human intelligence, the human brain will be depicted as responding to the intelligence contained within the surrounding environment—responsiveness after all being the activity traditionally reserved for neural systems.

Environmental Intelligence and Individual Intelligence. A fresh perspective can be gained on human intelligence by considering two orthogonal aspects—environmental intelligence and individual intelligence.

Environmental intelligence is defined as the total amount of non-biological pattern, structure and form tangibly contained within the human environment. This definition immediately ties human intelligence to the advancement of the human species. Prior to the human great leap forward, there would have been essentially no environmental intelligence to be found within the human surroundings, only natural settings, similar to all the other animals. But beginning with ostrich shell beads, bone awls, rudimentary clothing and cave paintings, and proceeding straight through to domesticated crops, mud-plastered abodes and towering pyramids, and crescendoing today in highways, skyscrapers, televisions and rockets to the moon, the one indisputable observation that can be made throughout that entire course of human progress is that no matter where man has found himself, he has found himself among an accumulating amount of non-biological pattern, structure, symmetry, repetition and form. Over the past fifty thousand years, man has been increasingly surrounded with environmental intelligence.

To actually measure environmental intelligence would be admittedly a pragmatic nightmare—the sheer enormity of pattern and structure contained within the modern world would alone overwhelm any genuine effort to size it, and furthermore, there could be no easy agreement on how to quantify structure contained within, for instance, an automobile or a library book. But these practical difficulties do not nullify the material certainty of measurement—environmental intelligence tangibly exists, one can touch it, hear it, talk about it, it exists right before one’s very eyes. Plus there is no need to actually measure environmental intelligence in order to attest to its ever increasing presence. Think of the North American continent alone. Only a few hundred years ago, man dwelled in but a handful of places there and the amount of non-biological environmental complexity would have been quite modest. But by one hundred years ago, man had taken up residence from nearly coast to coast and had augmented an entire patchwork of fields, houses and roads. Today one glance at the skylines of such cities as Chicago and Toronto would be more than sufficient to convince even the most dire skeptic that by almost any reasonable means of measurement, it would have to be calculated that the total amount of human environmental intelligence has been consistently on the rise.

The second, more familiar aspect of human intelligence, individual intelligence, is in many respects nothing at all like the first. Individual intelligence is defined as an individual’s capacity to absorb and respond to environmental intelligence, making it clear that individual intelligence is a secondary (a responding) construct. Nonetheless, the great value in this definition of individual intelligence is that it corresponds exactly to what gets measured on a modern intelligence test—IQ is an ideal quantification of individual intelligence. To see this, consider that the questions, the content, of an intelligence exam—language, arithmetic, geometrical patterns, and so on—these are constructed as proxies for environmental intelligence, and a person demonstrates his comparative capacity for mastering environmental intelligence by answering the questions correctly. Intelligence exams do not assess an individual’s abilities to scavenge food, ward off predators or procreate; instead everything that appears on an intelligence test emanates from the non-biological material artifacts that have been introduced into the human world over just the last several thousand years (and in some cases, over just the last tens of years). Therefore it is in no way surprising, just as psychometric analysis confirms, that those who are more successful in answering the proxies for environmental intelligence on an IQ exam are by and large the same individuals who are more successful at navigating a constructive path through the day-to-day surroundings of the modern world.

It is important to emphasize the orthogonal relationship of environmental intelligence and individual intelligence. Individual intelligence is a biological capacity, a human behavioral ability, and thus there is no objection to associating individual intelligence with neural and genetic causes. But environmental intelligence is not biological at all, it is instead a physical artifact, quantifiable within the material world, and it remains independent of any neurological or evolutionary constraint. Environmental intelligence and individual intelligence are each a crucial aspect upon human intelligence, but each delivers its influence in an entirely separate domain.

The Model. Armed with these definitions and descriptions of environmental intelligence and individual intelligence, it is a straightforward task to develop an illustrative example showing how these two aspects dynamically relate. All that is required from the reader is agreement that the practical difficulties in measuring environmental intelligence can be theoretically overcome, and consistent with observations from human history, environmental intelligence can be assumed to increase over any significant interval of time.

In the example to be developed, EIU (environmental intelligence unit) will be called upon as the arbitrary unit of measure, and the amount of non-biological pattern, structure and form in the hypothesized environment will be assumed to double from 200 EIU at time 1 to 400 EIU at time 2 (time 2 occurring several generations after time 1). All that then remains is to assess the intelligence scores of individuals at time 1 and compare these with the intelligence scores of individuals at time 2.

At time 1, the cognitive characteristics of three individuals—call them A1, B1 and C1—are assessed by means of a standard battery of intelligence tests. Since the content of these tests can be regarded as proxies for the environmental intelligence that exists at time 1, it is reasonable (although not strictly necessary) to state the results of these tests as percentages of environmental intelligence successfully mastered. For instance, when it is discovered that A1 can correctly answer 80% of the test questions, the result can be stated as follows: A1 has demonstrated the capacity to master roughly 80% of the environmental intelligence to be found around him. In a similar vein, when B1 and C1 respectively answer 70% and 60% of the test questions correctly, it can be said they are demonstrating the capacity to master corresponding percentages of environmental intelligence.

As is done with real world intelligence exams, the raw test scores of A1, B1 and C1 are normed and compared to the remainder of the test-taking population. From this procedure, it is determined that A1 falls within the comparative range of high intelligence for the general population, B1 falls within the range of average intelligence, and C1 falls within the range of low intelligence. The results are summarized in the following chart:

Time 1 (Environmental Intelligence: 200 EIU)

Test ScoresPopulation Rank
A180%High Intelligence
B170%Medium Intelligence
C160%Low Intelligence

At this point, all the standard types of analysis regarding individual intelligence differences can be performed quite adequately. Using relative intelligence rankings, and employing factor analysis and incorporating an assortment of statistical and biological information gathered from the population at large, scientists would be able to show with considerable confidence that, all other things being equal, A1 can expect greater success than his B1 and C1 peers in academics and career, and that the individual intelligence differences between A1, B1 and C1 can be attributed in large part to biological and genetic forces. The relative intelligence scores at time 1 (or at any given time) provide a wealth of information into the characteristics of individual intelligence.

An absolute measure of intelligence for A1, B1 and C1 has not yet been determined, but it is a simple matter to do so. With a measure of 200 EIU having been assigned to time 1’s environmental intelligence, and test results having been stated as a percentage of environmental intelligence effectively mastered, a quick multiplication reveals that A1’s absolute level of intelligence is 160 EIU (200 EIU x 80%), B1’s is 140 EIU, and C1’s is 120 EIU. The comparative chart can be updated to reflect these figures:

Time 1 (Environmental Intelligence: 200 EIU)

Test ScoresPopulation RankAbsolute Intelligence
A180%High Intelligence160 EIU
B170%Medium Intelligence140 EIU
C160%Low Intelligence120 EIU

This additional calculation of absolute intelligence scores does not aid at all in the understanding of individual intelligence; as far as intelligence differences are concerned, the inclusion of absolute scores is nothing but a superfluous addendum. The information, however, will prove to be invaluable. It will be essential in the comparison of intelligence characteristics between time 1 and time 2.

Time 2 occurs several generations after time 1, and so A1, B1 and C1 no longer exist. Nonetheless, it is a simple matter to summon their descendants—call them A2, B2 and C2—all of whom can be essentially regarded as biological and genetic equivalents to their ancestors. Indeed, when A2, B2 and C2 take the standard tests offered at time 2, they score in a familiar pattern. A2 answers 80% of the questions correctly, which is said to reflect an 80% mastery of time 2’s environmental intelligence, and B2 and C2, as to be expected, score 70% and 60% respectively. Once again these raw scores are normed and compared against the general population, and as with their ancestors, A2 falls within the range of high intelligence, B2 falls within the range of average intelligence, and C2 falls within the range of low intelligence:

Time 2 (Environmental Intelligence: 400 EIU)

Test ScoresPopulation Rank
A280%High Intelligence
B270%Medium Intelligence
C260%Low Intelligence

Factor analysis and population statistics reveal the same pattern of individual intelligence differences as were seen at time 1, and this is consistent with real world experience. Science has repeatedly shown that patterns of individual and group intelligence differences remain relatively stable across time—just as to be expected of individual intelligence, a characteristic determined in large measure by biological and genetic causes.

Nonetheless, at time 2, there has been a significant anomaly.

The first intelligence tests offered to A2, B2 and C2 were the very same tests offered to their ancestors at time 1, but as it turns out, A2, B2 and C2 have found those tests to be laughably easy. So easy in fact that they are no longer useful for the purpose of distinguishing individual intelligence abilities. In order to make the tests suitable again for comparative purposes, the test producers have had to beef them up, make the questions more difficult, and it is only after these modifications have been made that the tests can be effectively administered, with the resulting scores as shown.

In one sense, the reason that the tests have to be re-set is clear from the parameters of the illustrative example: since the content of an intelligence exam stands as a proxy for environmental intelligence, and since environmental intelligence has dramatically changed from time 1 to time 2—doubled in fact—the tests must be reconstituted in order to reflect this fact. But in another sense, the reason that tests have to be re-set is made clear from an entirely different source, namely that this is precisely what has been taking place in the real world throughout the previous century. Each successive generation has been scoring progressively better on older intelligence exams, to the point that test makers find they must modify the exams in order to keep them useful. These modifications generally take the form of more difficult questions, questions reflecting a greater amount of pattern, structure and form. In both the illustrative example and in the real world, intelligence tests have to be regularly strengthened in order to counteract the creeping influence of the Flynn effect.

And it is not just the tests that need to be reconsidered. Despite demonstrating equivalent levels of individual intelligence to their ancestors, indicating an equal capacity to absorb and respond to environmental intelligence, A2, B2 and C2 have nonetheless seen their absolute levels of intelligence take a quantum leap. With the time 2 environmental intelligence assessed at 400 EIU, A2’s test results reflect an absolute level of intelligence of 320 EIU (400 EIU x 80%). B2 weighs in at 280 EIU, and C2 scores at 240 EIU—in each case a doubling over A1, B1 and C1:

Time 2 (Environmental Intelligence: 400 EIU)

Test ScoresPopulation RankAbsolute Intelligence
A280%High Intelligence320 EIU
B270%Medium Intelligence280 EIU
C260%Low Intelligence240 EIU

It takes barely a moment’s reflection to recognize the sole cause for this quantum leap. It has nothing to do with individual intelligence. It has nothing to do with neurology or genetics. The sole driver of raw intelligence gains is the increasing amount of environmental intelligence, the increasing amount of pattern, structure and form tangibly contained within the human environment. Individual intelligence, the biological capacity to absorb and respond to environmental intelligence, that capacity remains constant over time, but that capacity encounters an ever expanding target.

Flynn's Paradoxes. In his book What is Intelligence?, Flynn (2007) describes four paradoxes he associates with the Flynn effect. The first paradox deals with g factor analysis, which is only tangentially related to the present discussion, but the remaining paradoxes can be resolved directly using this paper’s dual-aspect model of human intelligence.

Two of the paradoxes, labeled as the intelligence paradox and the mental retardation paradox, state the apparent incongruity that if the Flynn effect were literally true, then humans from one generation would be too implausibly dumb or too implausibly smart compared to humans from a different generation. In Flynn’s words:

If huge IQ gains are intelligence gains, why are we not struck by the extraordinary subtlety of our children’s conversation? Why do we not have to make allowances for the limitations of our parents? A difference of some 18 points in Full Scale IQ over two generations ought to be highly visible.

If we project IQ gains back to 1900, the average IQ scored against current norms was somewhere between 50 and 70. If IQ gains are in any sense real, we are driven to the absurd conclusion that a majority of our ancestors were mentally retarded. (p. 9–10)

The resolution to these two paradoxes is to recognize that Flynn is confusing the two different aspects of intelligence; he is confusing environmental intelligence with individual intelligence. In particular, he is using the changed levels in one aspect (environmental intelligence) to infer a corresponding change in the other aspect (individual intelligence). That inference is unwarranted.

In the illustrative example, consider the individual named A1. At time 1, A1 is assessed to be highly intelligent. He demonstrates his above-average ability to absorb and respond to environmental intelligence by correctly answering 80% of the test questions presented to him, and as A1 navigates through his time 1 world, it can be anticipated he will experience relatively greater achievement, compared for instance to his B1 and C1 peers.

But when A1’s absolute (raw) intelligence score of 160 EIU is compared to the population of time 2, A1 suddenly appears much less smart. 160 EIU scores far below the 240 EIU of C2, a person assessed to be of low intelligence at time 2. If 240 EIU is considered to be of low intelligence at time 2, then A1’s score of 160 EIU seems to mark him as a borderline imbecile.

So which is it? Is A1 highly intelligent or an imbecile? This paradox is resolved by recognizing that A1’s individual intelligence is not subject to change. A1’s absolute intelligence score of 160 EIU has as much to do with the time period during which it was registered as it has to do with A1’s biological capacity. If A1 could be magically transported forward in time and raised in the time 2 world, he would absorb and respond to about 80% of the time 2 environmental intelligence and would score correspondingly on a time 2 intelligence exam, making it clear once again that he is a highly intelligent individual. A1’s apparently low score of 160 EIU has nothing to do with A1’s intelligence abilities; it has everything to do with the change in environmental intelligence from time 1 to time 2.

This works exactly the same way going backwards in time. Consider C2, who is assessed at time 2 to be of low intelligence. But when C2’s absolute (raw) intelligence score of 240 EIU is compared to the time 1 population, where a score of 160 EIU is considered to be highly intelligent, C2 suddenly comes across as a Mensa candidate, and one wonders if C2 simply had the misfortune of being born too late.

So which is it? Is C2 of low intelligence or a Mensa candidate? Once again, the resolution is to recognize that C2’s individual intelligence is not subject to change. If C2 could be magically transported back in time and raised in the time 1 world, he would absorb only about 60% of the time 1 environmental intelligence and would score relatively poorly on the time 1 intelligence exam. The timing of one’s birth does not alter one’s personal intellectual ability.

In addition to these illustrative examples, Flynn provides a real world scenario that brings out the principle quite nicely. After noting that the average raw intelligence score from about 1900 would translate to an IQ of about 50 to 70 on today’s scale, Flynn raises the specter of the following tableau:

Jensen relates an interview with a young man with a Wechsler IQ of 75. Despite the fact that he attended baseball games frequently, he was vague about the rules, did not know how many players were on a team, could not name the teams his home team played, and could not name any of the most famous players.

When Americans attended baseball games a century ago, were almost half of them too dull to follow the game or use a scorecard? My father who was born in 1885 taught me to keep score and spoke as if this was something virtually everyone did when he was a boy. How did Englishmen play cricket in 1900? Taking their mean IQ at face value, most of them would need a minder to position them in the field, tell them when to bat, and tell them when the innings was over. (p. 23–24)

This is a quintessential example of mistaking a change in raw intelligence scores as evidence for a change in individual intelligence, when in fact it is evidence for a change in environmental intelligence.

Think about putting questions dealing with baseball rules on an intelligence test. If such questions had appeared on an intelligence exam in say 1800, no one at all, including the smartest people who then lived, would have been able to answer the questions correctly (other than by random luck). By contrast, if such questions were to appear on today’s intelligence exams, many individuals, including those of average intelligence, would be able to answer the questions correctly—baseball and its rules have become an established part of the human environment. As Flynn indicates, it would be only those with an IQ around 75 or under who would have limited potential to answer such questions correctly.

So does this mean that the smartest people from 1800 had the same intellectual capacity as Jensen’s young man? It does not mean that at all.

The crucial moment in time would have been around 1900. If intelligence questions regarding baseball rules had appeared on intelligence exams at that time, the results would have been mixed. Some people would have been able to answer the questions correctly, but others would not, including those of otherwise average-to-high intelligence, and this because baseball had not yet become widely entrenched within the human environment (it was just then catching on). But after the exam, if one of those baseball-ignorant persons of average-to-high intelligence had been taken to the ballpark, bought a ticket, sat with in the grandstands, explained the rules, given a scorecard and a pencil, a perfectly capable behavior would have swiftly emerged. After all, this is a person of average-to-high intelligence, he can absorb and respond to baseball rules just fine, they will give him not the slightest bit of trouble. And around 1900, this scene would have actually taken place—again and again and again.

The increase in raw intelligence scores from 1900 to 2000 has everything to do with the increasing amount of environmental intelligence (including the addition of baseball rules). It has nothing to do with individual intellectual abilities.

Flynn names his final paradox the identical twins paradox. Flynn’s words again:

There is no doubt that twins separated at birth, and raised apart, have very similar IQs, presumably because of their identical genes. Indeed a wide range of studies show that genes dominate individual differences in IQ and that environment is feeble. And yet, IQ gains are so great as to signal the existence of environmental factors of enormous potency. How can environment be both so feeble and so potent? (p. 10)

In considering Lewontin’s attempt to resolve this paradox, Flynn (p. 37) sorts through a list of candidates for an environmental Factor X—nutrition, education, liberal parenting, the scientific ethos—and dismisses each as not being widespread or potent enough to produce the requisite intelligence gains, concluding finally that one must “shut the door” on any further discussions of an environmental Factor X. But Flynn’s search is not nearly wide enough and is being hampered by a presumed environmental influence on human intellectual capacity—like nearly everyone else, Flynn does not countenance human intelligence freed of human neurology.

Environmental intelligence—the total amount of non-biological pattern, structure and form tangibly contained within the human environment, the countless structural, patterned artifacts humans live among and navigate day by day—that serves as the ideal Factor X. Environmental intelligence is ubiquitous. Environmental intelligence is constantly increasing. Environmental intelligence remains unfettered by the constraints of human biology, remains independent of the workings of individual intelligence.

An analogy to describe the relationship between environmental intelligence and individual intelligence would be to think of ships in a harbor, including lightweight ships such as pleasure craft and heavy duty ships such as battle cruisers. Were a measurement to be taken of the bottommost part of each ship (relative to a fixed vertical point on land), it would be discovered there are significant differences. Some ships will sit higher, some will sit lower. Further analysis of characteristics such as geometric structure and material density (equivalent to psychometric analysis) would reveal ship-based factors that determine relative vertical positions, exactly as scientists determine genetic and neurological factors that drive individual intelligence differences.

At a later point in time, measurements might reveal all the same relative differences in bottommost positions of the ships (with the same factors determining those differences), and yet it is also discovered that the absolute position of each ship (relative to the fixed vertical point on land) has risen by a significant amount. If the mistake is made of trying to explain this increase by appealing to the ships’ characteristics or by insisting that the ships’ environment must be somehow changing the ships’ characteristics, confusion will reign. The ships’ characteristics can explain relative vertical positions, but do nothing to explain absolute changes in position. For that, the context—the environment—of these ships must be taken fully and independently into account, leading eventually to the aphoristic conclusion that it is a rising tide that raises all ships.

In the orthogonal relationship between environmental intelligence and individual intelligence, environment is both feeble and potent, as is genetics—it all depends on the domain. Individual intelligence works through the auspices of human neurology, driven primarily by genetics. Environmental intelligence grows within the context of the physical, non-biological world, free of neurological constraint. Their influences seem paradoxical only when they become mistakenly intertwined (for instance, within the human brain), but when their impacts are kept properly separate, Flynn’s identical twins paradox swiftly disappears.

Environmental Complexity. Of the many offered explanations for the Flynn effect, the one most similar to the model proposed here is the notion of environmental complexity. Schooler (1998) and Greenfield (1998) offer perhaps the most comprehensive introductions to environmental complexity, and Wai & Putallaz (2011) provide a recent instance of the idea being invoked. But it can be seen in these and other discussions highlighting environmental complexity, that in several crucial respects, the explanation falls short.

The first problem with environmental complexity is that its proponents appeal to certain things within the human environment, instead of grasping the environment as a whole. Two commonly cited instances of environmental complexity are the increased use of video games and the complex and multivariate nature of television shows and movie plots; others note the expanded presence of visual puzzles and games. But no matter what thing or set of things is being considered, it becomes immediately clear that by itself it cannot account for the ubiquitous, relentless nature of the Flynn effect. The Flynn effect was working its magic long before there even were video games and television sets, and the Flynn effect remains prominent in locations where video games and sophisticated dramas have yet to take much hold. Any alternative candidate would fall victim to the same dilemma.

It is only by appealing to complete environmental complexity that traction can be gained. One way to envision complete environmental complexity would be to imagine the Earth’s surface as it stood nearly fifty thousand years ago and contrast that with how differently the Earth’s surface stands today. Every material artifact that has been introduced—every house, every road, every sign, every book, the whole entire lot—all of it forms the complete and expanding sum of environmental complexity. The types and examples of environmental complexity will differ from time to time and from place to place, but the one reliable constant is that the total amount of environmental complexity will be nearly always on the rise.

The second problem is that the proponents of environmental complexity—like nearly everyone else—attempt to tie their explanation back to human neurology. Playing video games, for instance, is seen as expanding the capacity of working memory. Modern movie plots perhaps form a larger number of connections within the logical neural circuitry. It would seem that environmental complexity by itself is deemed to be useless; its only purpose is to prompt a major restructuring within the neurons, a massive rewiring between the ears—a proposal that lacks both parsimoniousness and plausibility. The human brain does not need to be changed by environmental complexity, the human brain needs merely to absorb and respond—the simple and common basis of neurological behavior.

The Flynn effect is independent of individual intelligence differences, and thus an explanation for the Flynn effect should be independent of the human brain. If the proponents of environmental complexity are to hit the mark, they must come to accept environmental complexity as the material form of human intelligence itself; they must stop looking for expanding intelligence inside the human skull.

Conclusion. One immediate consequence of this paper’s dual-aspect model of human intelligence is that the Flynn effect cannot be regarded as a twentieth-century anomaly. Tracking the increase in environmental intelligence, the Flynn effect would have begun at the time of the human great leap forward and has been shadowing human existence ever since, and there is no reason to expect it will end anytime soon.

Environmental intelligence, the increasing amount of pattern, structure and form tangibly contained within the human environment—that is the unseen hand propelling intelligence scores ever upward. That it has remained unseen for so long should not be that surprising; it is a frequent human experience that the thing most difficult to perceive is the thing that exists right before one’s very eyes.


Flynn, J. R. (1999). Searching for justice: The discovery of IQ gains over time. American Psychologist, 54, 5–20.

Flynn, J. R. (2007). What is intelligence? Beyond the Flynn effect. New York: Cambridge University Press.

Greenfield, P. (1998). The cultural evolution of IQ. In U. Neisser (Ed.), The rising curve. Washington, DC: American Psychological Association.

Lewontin, R. C. (1976). Further remarks on race and the genetics of intelligence; Race and intelligence. In N. J. Block & G. Dworkin (eds.), The IQ controversy. New York: Pantheon Books.

Schooler, C. (1998). Environmental complexity and the Flynn effect. In U. Neisser (Ed.), The rising curve. Washington, DC: American Psychological Association.

Wai, J., & Putallaz, M. (2011). The Flynn effect puzzle: A 30-year examination from the right tail of the ability distribution provides some missing pieces. Intelligence, 39, 443–455.

Tuesday, February 14, 2012

Introduction to a Paper

Tomorrow I'm going to post a paper here, and I think it might need a little explanation.

The paper's content will be familiar. Last fall, I scrambled together a quick series of posts on the Flynn effect (Flynn Effect 101, Flynn Effect 102, Flynn Effect 103, and Flynn Effect 104) and I've had a hankering ever since to reorganize that material into a single, more cohesive essay. Last month I finally got the opportunity to do so and tomorrow's post is the result.

For me, this paper is extremely formal. The reason for the formality is that I felt I should submit the paper at least once for publication, which I did, to the journal Intelligence. (No surprise, the paper was deemed “not suitable for a scientific journal.”) I didn't struggle with the rigidity of the format as much as I thought I would (although admittedly I bent a few of the rules), but the experience left me wondering why so many people would voluntarily submit to such confinement—the academic community never ceases to amaze me.

At any rate, for the few who might be interested in a different approach to describing human intelligence, tomorrow's essay is my semi-formal attempt to fit the bill.