CHAPTER 32 Secular Changes in Intelligence

James R. Flynn

Whether the 20th century has seen intelli- tests were not among those used by clini- gence gains is controversial. Whether there cal psychologists, the practical implications have been massive IQ gains over time is not. were ignored. It was when Flynn (1984, 1987) This difference orders my task. I will (1) showed that massive gains had occurred in describe the range and pattern of IQ gains; the United States on Wechsler and Stanford- (2) discuss their cognitive significance; (3) Binet IQ tests, and that they had occurred describe their significance for today’s world; throughout the industrialized world, even (4) argue that they suggest a new theory of on tests thought to be pure measures of intelligence; (5) speculate about what may intelligence, that IQ gains took center stage. happen during the 21st century. Within a decade, Herrnstein and Murray (1994), the authors of The Bell Curve, called the phenomenon “the Flynn effect.” The Evidence and Its Peculiarities Nations with data about IQ trends stand at 30. Scandinavian nations show that IQ Reed Tuddenham (1948) was the first to gains may not last much beyond the end present convincing evidence of massive gains of the 20th century, at least in the devel- on mental tests using a nationwide sam- oped world. Their scores peaked about ple. He showed that U.S. soldiers had made 1990 and since then, may have gone into about a 14-point gain on Armed Forces tests mild decline. Several other nations still between World War I and World War II show robust gains. Americans are still gain- or almost a full standard deviation (SD = ing at their historic rate of 0.30 points 15 throughout). The tests in question had per year (WAIS 1995–2006;WISC1989– a high loading on the kind of material 2002). British children were a bit below taught in the classroom and he thought the that on Raven’s from 1980 to 2008,but gains were primarily a measure of improved their current rate of gain is higher than schooling. Therefore, they seemed to have in the earlier period from 1943 to 1980. no theoretical implications, and because the Other gains cover long periods, so whether

647 648 JAMES R. FLYNN the rate varied approaching the present is American gains have been on the most fre- unknown. Urban Argentines (ages 13 to 24) quently used tests, namely, the Wechsler made a 22-point gain on Raven’s between tests. Both the WISC (Wechsler Intelligence 1964 and 1998. Children in urban Brazil Scale for Children) and the WAIS (Wech- (1930–2002), Estonia (1935–1998), and Spain sler Adult Intelligence Scale) show full-scale (1970–1999) made gains akin to the U.S. IQ gains proceeding at 0.30 points per year rate (Colom, Lluis Font, & Andres-Pueyo, over the last half of the 20th century, a rate 2005; Colom, Flores-Mendoza, & Abad, often found in other nations, for a total gain 2007; Emanuelsson, Reuterberg, & Svensson, of over 15 points. If we link this to ear- 1993; Flynn, 2009a,b,c; Flynn & Rossi-Case,´ lier data, like that of Tuddenham, the gain under review; Must, Must, & Raudik, 2003; over the whole 20th century has been at Schneider, 2006; Sundet, Barlaug, & Tor- least 30 points. Second, for children, there jussen, 2004; Teasdale & Owen, 1989, 2000). is a marked contrast between small gains The developing world shows explosive on subtests close to school-taught subjects gains in rural Kenya and the Caribbean. In (Information, Arithmetic, Vocabulary) and Sudan, large fluid gains (WAIS Performance large gains on subtests that require solving Scale) were accompanied by a small loss for a problem on the spot (Picture Comple- crystallized intelligence (Daley et al., 2003; tion, Block Design, Coding). The former are Khaleefa, Sulman, & Lynn, 2009; Meisen- often classified as crystallized subtests, those berg et al., 2005). If third-world nations con- that measure what an intelligent person is tinue to gain over the 21st century, and the likely to learn over a lifetime, and the latter developed nations do not, the present IQ as fluid subtests, those that measure intelli- gap between the two will disappear. gence by forcing you to solve problems in Dutch data illustrate why IQ gains were the test room for which you have no previ- so disturbing. Between 1952 and 1982, young ously learned method. Dutch males gained 20 IQ points on a test This WISC pattern of larger gains on fluid of 40 items selected from Raven’s Progres- than crystallized subtests is international. sive Matrices (Flynn, 1987). The sample was For example, Raven’s gains are huge every- exhaustive. Raven’s was supposed to be the where and it is the epitome of a fluid test: exemplar of a culturally reduced test, one You study a matrix pattern with a piece that should have shown no gains over time missing and must recognize that piece from as culture evolved. These 18-year-olds had alternatives, only one of which is correct. reached the age at which performance on For later reference, look at the bottom of the Raven’s peaks. Therefore, their gains could table and note the huge gains on the Simi- not be dismissed as early maturation, that is, larities subtest, which is a measure of the it was not just a matter that children today ability to classify and defies to some degree matured about two years earlier than the the crystallized/fluid dichotomy. Also note children of yesterday. Current people would a new peculiarity that has just come to light. have a much higher IQ than the last gener- Adults differ from children: The fluid gains ation even after both had reached maturity. of the latter are five times their crystallized These gains created a crisis of confidence: gains, while the fluid gains of the former are How could such huge gains be intelligence only slightly greater. This is largely because gains? The gains amounted to 1.33 SDs. This since 1950, U.S. children have made only would put the average Dutchman of 1982 a minimal vocabulary gain of 4.40 points, at the 90th percentile of Dutch in 1952.Psy- while U.S. adults have made a huge gain of chologists faced a paradox: Either the people 17.80 points. It is not yet known whether this of today were far brighter than their parents is an international phenomenon. Other U.S. or, at least in some circumstances, IQ tests data suggest that the growing discrepancy were not good measures of intelligence. between U.S. adults and their children is Table 32.1 reveals some of the peculiar- largely active vocabulary, the words you use, ities of IQ gains. First, it shows how large rather than passive vocabulary, the words SECULAR CHANGES IN INTELLIGENCE 649

Table 32.1. American WISC (Schoolchildren) and WAIS (Adults) Gains

Rising Full-Scale IQ 1947.5 1972 1989 2001.75

WISC 100.00 107.63 113.00 117.63 1953.5 1978 1995 2006 WAIS 100.00 107.50 111.70 115.07

Contrast between gains on crystallized and fluid subtests (over a shared period of 54 years)

WISC WAIS

Information (C) 2.15 8.40 Arithmetic (C) 2.30 3.50 Vocabulary (C) 4.40 17.80 Average crystallized 2.95 9.90 Picture Completion (F) 11.70 11.20 Block Design (F) 15.90 10.25 Coding (F) 18.00 16.15 Average fluid 15.20 12.53

Subtests ranked by the difference between adult and child gains (over a shared period of 54 years)

Difference IQ points Difference percentages WAIS – WISC Points WAIS/WISC Percentages

Vocabulary 17.80 − 4.40 = 13.40 17.80 / 4.40 = 405 Information 8.40 − 2.15 = 6.25 8.40 / 2.15 = 391 Comprehension 13.80 − 11.00 = 2.80 13.80 /11.00 = 125 Arithmetic 3.50 − 2.30 = 1.20 3.50 / 2.30 = 152 Picture Completion 11.20 − 11.70 =−0.50 11.20/ 11.70 = 96 Coding 16.15 − 18.00 =−1.85 16.15/ 18.00 = 92 Similarities 19.55 − 23.85 =−4.30 19.55/23.85 = 82 Block Design 10.25 − 15.90 =−5.65 10.25/ 15.90 = 64

Sources: Flynn, 2009b; 2009c; under review-b. you understand when you hear them used the adult speech community as they age and (Flynn, under review-b). participate in the world of work. The only thing that can be said at present The pattern of IQ gains over time has is that the discrepancy does not seem to be a final peculiarity, namely, it is not con- because adults have their university educa- sistently factor-invariant (Wicherts et al., tion behind them, while their children are 2004). Factor analysis is a technique that still in school. Perhaps it is symptomatic of a measures the extent to which those who trend over the last 50 years for U.S. teenagers excel on some IQ subtests also excel on oth- to retreat into the subculture of their peers ers. The tendency toward general excellence with its own peculiar dialect; and then join is not peculiar to cognitive tests. Just as those 650 JAMES R. FLYNN who have larger vocabularies also tend to be thesmallestgainmaybeonasubtestwith better at arithmetical reasoning and solving an above-average g-loading. This convinced matrices problems, so people who are good Jensen (1998) that the bulk of IQ gains were at one musical instrument are often good at not g gains and therefore, were not intelli- another, and people good at one sport are gence gains. He suggests that IQ gains may often good at almost all sports. The measure be largely “hollow,” that is, they are a bun- of the tendency for a variety of skills to inter- dle of subtest-specific skills that have little correlate is call g (the general intelligence real-world significance. factor). If the top person on one subtest of the WISC topped all the others, and so on down the line, g would “explain” 100 per- Two Kinds of Significance cent of the pattern of test performance and have a value of 1.00. If a person’s score on Before we accept the interpretation of IQ each subtest were no more of an indication gains as hollow, it is useful to supplement of their performance on any other subtest factor analysis with functional analysis. Fac- than a score chosen at random, g would be tor analysis may disclose latent traits but no zero. one can do latent traits. What we do in the One subtest may have a higher g-loading real world is perform, better or worse, func- than another. This means that it is a better tional activities, such as speaking, solving guide as to who will do well on the other arithmetic problems, and reasoning about subtests. For example, if you added an 11th scientific and moral questions. To contrast WISC subtest on shoe tying, it would have the two kinds of analysis, I will use a sports a g-loading of close to zero: How fast you tie analogy. your shoes would have little relation to the If we factor analyzed performances on size of your vocabulary. On the other hand, the 10 events of the decathlon, a gen- your score on the Vocabulary subtest might eral factor or g would emerge and very be a pretty good predictor of your scores on likely subordinate factors representing speed the other subtests (except shoe tying) and (the sprints), spring (jumping events), and get a g-loading of 0.75. You could then rank strength (throwing events). We would get a the subtests into a hierarchy according to the g because at a given time and place, perfor- size of their g-loadings. When this is done, manceonthe10 events would be intercor- it is evident that the skills with the great- related, that is, someone who tended to be est cognitive complexity top the g-loading superior on any one would tend to be above hierarchy, which is to say that the more average on all. We would also get various complex the task, the greater will be the g-loadings for the 10 events, that is, supe- gap between high-IQ people and the average rior performers would tend to rise further person. This seems to give g a good case to above average on some of them than on the be identified with intelligence and suggests others. The 100 meters would have a much that there might be a latent trait, general higher g loading than the 1,500 meters, which intelligence; and that to the extent to which involves an endurance factor not clearly nec- a person possesses that trait, the better he essary in the other events. or she will do on a whole range of cognitive Decathlon g might well have much util- tasks. ity in predicting performance differences We can now understand why it is thought between athletes of the same age cohort. significant that IQ gains are not consistently However, if we used it to predict progress factor invariant. As far as g is concerned, over time and forecast that trends on the 10 this means that when we rank subtests by events would move in tandem, we would their g-loadings, we find that the magnitude go astray. That is because decathlon g can- of IQ gains on the various subtest does not not discriminate between pairs of events in tally: The largest IQ gain over time may be terms of the extent to which they are func- on a subtest with an average g-loading and tionally related. SECULAR CHANGES IN INTELLIGENCE 651

Let us assume that the 100 meters, the hurdles because speed between the hurdles hurdles,andthehighjumpallhadlarge is important. But it is only half the story: and similar g loadings, as they almost cer- You have to control your speed so that you tainly would. A sprinter needs upper body take the same number of steps between hur- strength as well as speed, a hurdler needs dles and always jump off the same foot. If speed and spring, a high jumper needs spring you told these coaches that you found it and timing. I have no doubt that a good ath- surprising that real-world shifts in priorities, lete would best the average athlete handily and the real-world functional relationships on all three at a given place and time. How- between events, ignored the factor loadings ever, over time, social priorities change. Peo- of the events, they would find your mind-set ple become obsessed with the 100 meters as surprising. the most spectacular spectator event (the Back to the WISC subtests: Arithmetic, world’s fastest human). Young people find Information, Vocabulary, and Similarities all success in this event a secondary sex char- load heavily on g and on a shared verbal acteristic of great allure. Over 30 years, per- factor. Despite this, as Table 32.1 shows, formance escalates by a full SD in the 100 between 1947 and 2002, American children meters, by half a standard deviation in the gained 24 points on Similarities, 4 points on hurdles, and not at all in the high jump. Vocabulary, and only 2 points on Arithmetic In sum, the trends do not mimic the and Information. This is to say that the pat- relative g loadings of the “subtests.” One tern of gains bears little relation to factor pair of events highly correlated (sprint and loadings and cannot qualify as factor invari- hurdles) shows a modest trend for both to ant. However, as usual, factor analysis was move in the same direction and another pair done in a static setting with social change equally highly correlated (sprint and high held constant. It has no necessary applica- jump) shows trends greatly at variance. Fac- bility to the dynamic scenario of social pri- tor loadings have proved deceptive about orities altering over time. Thus, g-loadings whether various athletic skills are function- turn out to be bad guides as to which real- ally independent. We can react to this in two world cognitive skills are merely correlated ways: Either confront the surprising auton- and which are functionally related. To antic- omy of various skills and seek a solution ipate, a social change over time like people by depth analysis of how they function in putting on scientific spectacles might greatly the real world; or deny that anything real enhance the ability to classify (Similarities) has happened and classify the trends over without affecting everyday vocabulary or time as artifacts. The second option is ster- fund of general information. Nonetheless ile. It is equivalent to saying that if trends all of these trends would be of great sig- are not factor invariant, they are artifacts by nificance, and to dismiss them as “hollow” definition. would be a barrier to understanding the cog- It is better to talk to some athletics nitive history of our time. coaches. They tell us that over the years, everyone has become focused on the 100 meters and it is hard to get people to take Interpretation and Causes other events as seriously as in the past. They point out that sprint speed may be highly Ideally, everyone would approach the cause correlated with high jump performance but of massive IQ gains evidentially. But past a certain point, it is actually counter- inevitably, a scholar’s interpretation of their productive. If you hurl yourself at the bar significance affects his or her list of what at maximum speed, your forward momen- causes seem most likely. tum cannot be converted into upward lift If you think that IQ trends are significant and you are likely to time your jump badly. as barometers of a shift in cognitive prior- They are not surprised that increased sprint ities over time, you are likely to focus on speed has made some contribution to the cultural factors. But if you believe that they 652 JAMES R. FLYNN are mainly hollow with a residue that is true greater IQ gains in the lower half of the IQ intelligence or g gains, and that g is a latent curve than the upper half. The assumption is trait that has its home in brain physiology, that even in the past, the upper classes were you will turn to causes that might affect well fed, while the nutritional deficiencies brain physiology, such as improved nutri- of the lower classes have gradually dimin- tion or hybrid vigor (Lynn, 1989, 1990, 1993, ished. IQ gains have been concentrated in 1998; Migronni, 2007). The latter refers to the lower half of the curve in Denmark, the fact that too much inbreeding is a nega- Spain, and Norway, but not in Argentina, tive influence on a whole range of human France, the Netherlands, and the United traits including intelligence, as inbreeding States. Norway is actually a counterexam- between first and second cousins eventually ple: Height gains were larger in the upper produces IQ deficits. If a nation’s popula- half of the distribution while IQ gains were tion was divided at the beginning of the 20th higher in the lower half (Sundet, Barlaug, & century into small and inbred communities Torjussen, 2004). It is unlikely that enhanced and then, over time, became more mobile, nutrition both raises height more than IQ it would reap the benefits of out-breeding and IQ more than height. British trends are (hybrid vigor) and the nation’s mean IQ fatal. They do not show the IQ gap between would rise. the top and bottom halves reducing over The evidence calls enhanced out- time. The difference was large on the eve breeding into question as an important of the Great Depression, contracted 1940 to cause, at least in developed nations in the 1942, expanded 1964 to 1971, contacted 1972 20th century. America was never a collec- to 1977, and has expanded ever since. No tion of isolated communities that discovered coherent dietary history of England can offer geographical mobility only in the 20th cen- the alteration of feast and famine needed to tury. Right from the start, there was a huge explain these trends (Flynn, 2009a, 2009c). influx of migrants who settled in both urban As noted, those who think IQ trends are and rural areas. There were major popula- barometers that register a shift in cognitive tion shifts during settlement of the West, priorities over time will look toward cultural after the Civil War, and during the World evolution for causes. Flynn (2009a)tried Wars. The growth of mobility has been mod- to simplify the explanatory task by focus- est: In 1870, 23% of Americans were living in ing on the observation that the largest IQ a state other than the one of their birth; in gains were on Raven’s Progressive Matrices 1970, the figure was 32% (Mosler & Catley, and the Similarities subtest of the Wechsler 1998). Recent data from Norway compare battery. the scores of males as they reach 18 with the He asked what “habits of mind” people scores of their older siblings who reached needed to get the right answers as given 18 a few years earlier. If the younger sib- in the scoring manuals. Take Similarities: ling outscores the older, this signals an IQ When asked, “What do dogs and rabbits gain over time (the reverse would signal a have in common?” the correct answer is that loss over time). The IQ trends yielded by “they are both mammals” rather than “we these comparisons exactly match the mag- use dogs to hunt rabbits.” The right answer nitude of the nation’s IQ trends (Sundet assumes that you are conditioned to look at et al., in press). Because siblings cannot the world through scientific spectacles – as differ in their degree of out-breeding, this something to be understood by classification shows that hybrid vigor has not been a factor rather than through utilitarian spectacles – in modern Scandinavia. If it had, the within- as something to be manipulated to advan- sibling estimate would fall short of the actual tage. Raven’s is all about using logic to deal trend. with sequences of abstract shapes that have In the developed world, better nutri- no counterpart in concrete reality. If a mind tion was probably a factor before 1950,but is habituated to taking hypothetical prob- not since. The nutrition hypothesis posits lems seriously and to using logic to deal with SECULAR CHANGES IN INTELLIGENCE 653 the hypothetical, this seems perfectly natu- terms of abstract categories. The Similarities ral. If you are unaccustomed to using logic subtest assumes exactly the opposite, that for anything but to deal with the concrete is, it damns the concrete in favor of the world, and indeed distrust reasoning that is abstract. not grounded in the concrete, you are unac- Here is an interview about using logic to customed to the change of gears that Raven’s analyze the hypothetical: requires. Like classification, the reasoning rewarded is of the sort that science, which Camels and Germany (Luria, 1976,p.112) is all about taking explanatory hypotheses seriously, entails. Q: There are no camels in Germany; The next step is rather like an archaeo- the city of B is in Germany; are there logical excavation: Dig into the past hop- camels there or not? ing to find evidence that appears relevant A: I don’t know, I have never seen Ger- and assemble it bit by bit. Fortunately, Luria man villages. If B is a large city, there recorded interviews with isolated rural peo- should be camels there. ple (Russians in the 1920s) who still lived in Q: But what if there aren’t any in all of prescientific cognitive environments. Here is Germany? one about classification: A: If B is a village, there is probably no room for camels. Fish and Crows (Luria, 1976,p.82) Today, we are accustomed to detaching Q: What do a fish and a crow have in logic from the concrete, and say, “of course common? there would be no camels in this hypothet- A: A fish – it lives in water. A crow flies. ical German city.” The person whose life If the fish just lies on top of the water, is grounded in concrete reality rather than the crow could peck at it. A crow can in a world of symbols is baffled. Who has eat a fish but a fish can’t eat a crow. ever seen a city of any size without camels? Q: Could you use one word for them The inhibition is not primarily due to lim- both? ited experience but rather to a refusal to A: If you call them “animals,” that treat the problem as anything other than wouldn’t be right. A fish isn’t an ani- concrete. Imagine that the syllogism said mal and a crow isn’t either. A crow there were no dogs in a large German city. can eat a fish but a fish can’t eat a The concrete response is that there must be bird. A person can eat a fish but not a dogs in German cities – who would want crow. or be able to exterminate them all? And if one is not practiced in dealing with using Note that even after an abstract term is logic on hypothetical problems that at least suggested, the “correct” answer is still alien. use concrete imagery, what of the hypo- Today we are so familiar with the cate- thetical problems of Raven’s that are stated gories of science that it seems obvious that in terms of abstractions with no concrete the most important attribute things have in referent? common is that they are both animate, or Unlike today, when we are bombarded mammals, or chemical compounds. How- with symbols, the Americans of 1900 had a ever, people attached to the concrete will poverty of experience with such. The only not find those categories natural at all. First, artificial images they saw were drawings or they will be far more reluctant to clas- photographs, both of which tended to be sify. Second, when they do classify, they representational. Aside from basic Arith- will have a strong preference for concrete metic, nonverbal symbols were restricted to similarities (two things look alike, two ani- musical notation (for an elite) and play- mals are functionally related, for example, ing cards (except for the religious). They one eats the other) over a similarity in saw the world through utilitarian spectacles: 654 JAMES R. FLYNN

Their minds were focused on ownership, the Interpretation and Effects useful, the beneficial, and the harmful; and not on the hypothetical and abstract classi- There is another avenue toward enhanced fication. plausibility. Make “predictions” about what Genovese (2002) has done his own dig we ought to find in the real world – if trends into America’s past. He compared the on the WISC subtests are clues to the evolu- exams the state of Ohio gave to 14-year-old tion of functional skills rather than “hollow.” schoolchildren between 1902 and 1913 and Here are a half a dozen: (1) Tutoring chil- between 1997 and 1999. The former tested dren on Raven’s should do little to improve for in-depth knowledge of culturally valued their mathematical problem-solving skills. information; the latter expected only super- (2) Enhanced performance on school read- ficial knowledge of such information and ing and English courses should decline after tested for understanding complex relation- the age of 14.(3) Enhanced performance ships between concepts. The former were in school mathematics should show the likely to ask you to name the capitals of same pattern. (4) Popular entertainment the (then) 48 states. The latter tended to should be more cognitively complex and ask you why the largest city of a state was less ”literal” in its plot lines. (5) Cognitively rarely the state capital (rural members dom- demanding games like chess should show inated state legislatures, hated the big city, large performance gains over time. (6) The and bestowed the capital on a rural town). quality of moral and political debate should Genovese (2002,p.101) concludes: “These have risen over time. findings suggest that there have been sub- It is tempting to identify mathematical stantial changes in the cognitive skills val- thinking with the cognitive problems posed ued by Ohio educators over the course of by Raven’s. Raven’s demands that you think the 20th century.” We now have a clue out problems on the spot without a pre- as to why there have been virtually no viously learned method for doing so, and score gains on the WISC general information Mathematics requires mastering new proofs subtest. dealing with nonverbal material. They are Thus far, the proffered causes of the huge highly correlated in terms of factor loadings, gains on Similarities and Raven’s have to which seems to signal that they require sim- do with the minds that took the tests. A ilar cognitive skills. Therefore, it seems sen- full analysis would be multilayered. The sible to teach young children Raven’s-type ultimate cause of IQ gains is the Indus- problems in the hope that they will become trial Revolution. The intermediate causes better mathematics problem solvers. U.S. are probably its social consequences, such schools have been doing that since 1991 as a better ratio of adults to children, richer (Blair, Gamson, Thorne, & Baker, 2005, interaction between parent and child, better pp. 100–101). schooling, more cognitively demanding jobs, Here IQ gains validate their credentials and cognitively challenging leisure (Neisser, as a diagnostician of functional relationships 1998). Donning scientific spectacles with between cognitive skills. The large gains the attendant emphasis on classification on Raven’s since 1950 and the virtually nil and logical analysis is only the proximate gains on Arithmetic (see Table 32.1) show cause. that the relationship between the two is In fairness, biological causes like hybrid no more functional than the relationship vigor and nutrition are usually precise between sprinting and the high jump. Sadly, enough to be at risk of falsification. Cul- our understanding of the functional process tural history, like all history, suggests causes for learning Arithmetic is far behind our that may be plausible but difficult to quan- understanding of the high jump. Some spec- tify and test. More digging is needed if the ulation: Except for mathematicians who scenario offered herein is to inspire confi- link the formulas with proofs, mathemat- dence. ics is less a logical enterprise than a separate SECULAR CHANGES IN INTELLIGENCE 655 reality with its own laws that are at variance To hold fast where a steel chain snaps, with those of the natural world. Therefore, And leave the grand white neck no gash just as infants explore the natural world, children must explore the world of mathe- If you do not know what the Kremlin is, matics themselves and become familiar with or what “serpentine” means, or that taking its “objects” by self-discovery. snuff involves using a snuff rag, you will Subtests that show minimal gains have hardly realize that these generals caught the as much explanatory potential as those that czar unaware and strangled him. show huge gains. Since 1950, there have In other words, today’s schoolchildren been very minimal gains on the WISC sub- opened up an early lead on their parents tests that measure whether children have (who were schoolchildren circa 1972)by an adequate fund of general information learning the mechanics of reading at an ear- and a decent vocabulary and whether they lier age. But by age 17, their parents had can reason arithmetically (Table 32.1). These caught up. And because current students are very close to school-taught skills. Let are no better than their parents in terms of us see what they tell us about U.S. trends vocabulary and general information, the two on the National Association of Educational generations at 17 are dead equal in their abil- Progress (NAEP) tests, often called the ity to read the adult literature expected of a nation’s report card. senior in high school. The NAEP tests are administered to large From 1973 to 2000, the Nation’s Report representative samples of 4th-, 8th-, and Card shows 4th- and 8th-graders making 12th-graders. From 1971 to 2002, 4th- and 8th- mathematics gains equivalent to almost graders (average age 11 years old) made a seven IQ points. These put the young chil- reading gain equivalent to almost four IQ dren of 2000 at the 68th percentile of their points. However, by the 12th grade, the read- parents’ generation. But once again, the gain ing gain drops off to almost nothing (U.S. fallsoffatthe12th grade, this time to lit- Department of Education, 2000, pp. 104, 110; erally nothing (U.S. Department of Educa- 2003,p.21). The IQ data suggest an inter- tion, 2000,pp.54, 60–61; 2001,p.24). And esting possibility. For the sake of compara- once again, the relevant WISC subtest sug- bility, we will focus on WISC trends from gests why. 1972 to 2002, rather than on the full period The Arithmetic subtest and the NAEP beginning in 1947. Between 1972 and 2002, mathematics tests present a composite pic- U.S. schoolchildren made no gain in their ture. An increasing percentage of young chil- store of general information and only mini- dren have been mastering the computational mal vocabulary gains (Flynn, 2009c). There- skills the Nation’s Report Card empha- fore, while today’s children may learn to sizes at those ages. However, WISC Arith- master preadult literature at a younger age, metic measures both computational skills they are no better prepared for reading more and something extra. The questions are put demanding adult literature. verbally and often in a context that requires You cannot enjoy War and Peace if you more than a times-table-type answer. For have to run to the dictionary or encyclope- example, take an item like this: “If 4 toys dia every other paragraph. Take Browning’s cost $6, how much do 7 cost?” Many subjects poem: who can do straight paper calculations can- not diagnose the two operations required: Over the Kremlin’s pavement bright that you must first divide and then multiply. With serpentine and syenite, Others cannot do mental arithmetic involv- Steps, with other five generals ing fractions. In other words, WISC Arith- That simultaneously take snuff, metic also tests for the kind of mind that is For each to have pretext enough likely to be able to reason mathematically. And kerchiefwise unfold his sash My hypothesis is that during the period Which, softness self, is yet the stuff in which children mastered calculating skills 656 JAMES R. FLYNN at an earlier age, they made no progress the decline in the age of chess grandmasters. in acquiring mathematical reasoning skills. There is no doubt that the standard of play Reasoning skills are essential for higher in chess tournaments has risen (Nunn, 1999). mathematics. Therefore, by the 12th grade, Howard makes the same case, although the failure to develop enhanced mathemati- the evidence is less compelling, for feed- cal problem-solving strategies begins to bite. back loops in other leisure activities that American schoolchildren cannot do Algebra are cognitively demanding such as bridge and Geometry any better than the previous and go. generation. Once again, although the previ- Has the quality of political debate risen ous generation was slower to master com- over the 20th century? Rosenau and Fagan putational skills, they were no worse off at (1997) compare the 1918 debate on women’s graduation. suffrage with recent debates on women’s We turn to the worlds of leisure and pop- rights and make an excellent case that the ular entertainment. Greenfield (1998) argues latter shows less contempt for logic and rel- that videogames, popular electronic games, evance. Note the setting, namely, debate and computer applications cause enhanced that goes into the Congressional Record. problem solving in visual and symbolic con- That members of Congress have become texts; if that is so, that kind of enhanced unwilling to give their colleagues a mind- problem solving is necessary if we are to fully less harangue to read does not mean that all enjoy our leisure. Johnson (2005) points to forms of political debate have improved. the cognitive demands of videogames, for We need more research with a proper example, the spatial geometry of Tetris, the focus. I suspect that improvement has been engineering riddles of Myst, and the map- limited to written material of some length, ping of Grand Theft Auto. that is, material designed to persuade the However, Johnson’s most important con- solitary reader who can take as long as he or tribution is his analysis of television. TV she likes to mull over what is said. I antic- aims at a mass audience and therefore, ipate no improvement in two categories. its level of cognitive complexity is based First, speeches to live audiences meant to on an estimate of what the average per- reduce them to an unthinking mob. William son can assimilate. Johnson shows convinc- Jennings Bryan’s dreadful “Cross of Gold” ingly that today’s popular TV programs speech sets the standard for stump oratory make unprecedented cognitive demands. today as much as it did over a century ago. The popular shows of a generation ago, such Second, there are media events in which the as ILoveLucyand Dragnet and Starsky and speaker has a few minutes to pack in the Hutch, were simplistic, requiring virtually no most effective sound bites. This is the natu- concentration to follow. Beginning in 1981 ral arena of the spin doctor and its standard with Hill Street Blues, single-episode drama was set in New Zealand by a candidate who began to be replaced with dramas that wove catapulted his party up the polls by using together as many as 10 threads into the plot the words “family,” “moderate,” and “rea- line. A recent episode of the hit drama 24 sonable” more often in five minutes than connected the lives of 21 characters, each one would think possible. What we need with a distinct story. is a survey covering 50 years of news sto- Howard (1999) uses traditional games ries and opinion essays in semiserious pub- as an informal measure of cognitive gains. lications like Newsweek and the New York He speaks of “cascading feed-back loops”: Times. More people want to play chess, the average I know of no study that measures whether skill rises, chess clubs form, coaching and the quality of moral debate has risen chess books improve with rising demand, over the 20th century. However, I will so you have even better average perfor- show why it should have. The key is that mance, and so on. He evidences the trend more people take the hypothetical seriously, toward enhanced skills by documenting and taking the hypothetical seriously is a SECULAR CHANGES IN INTELLIGENCE 657 prerequisite to getting serious moral debate Performance subtests: Large gains on off the ground. When my brother and I these are more difficult to interpret. would argue with our father about race, and Certainly, the gains on Block Design when he endorsed discrimination, we would signal enhanced ability to solve on the say, “But what if your skin turned black?” A spot problems that require more than man born in 1885, and firmly grounded in the mere application of learned rules. the concrete, he would reply, “That is the Comprehension: Since 1947, adults have dumbest thing you have ever said – whom gained the equivalent of almost 14 do you know whose skin has ever turned IQ points and children 11. This sub- black?” I have never encountered contem- test measures the ability to com- porary racists who responded in that way. prehend how the concrete world is They feel that they must take the hypothet- organized (why streets are numbered ical seriously, and see that they are being in sequence). The greater complexity challenged to use reason detached from the of life today seems to pose a chal- concrete to show that their racial judgments lenge the average person has risen to are logically consistent. The possibility of meet. better moral debate is so important that it Information: Over 8 points for adults but too must be subject to systematic investi- only 2 points for children. Presumably gation. this reflects the influence on adults of We can now offer a summary of the real- the expansion of tertiary education. world implications of IQ gains. Not IQ gains Arithmetic: The small gains here reveal as such, of course, because they have no the failure of education on any level to real-world implications. Rather, it is a sum- significantly improve arithmetical rea- mary of the real-world effects of the cogni- soning. tive trends that IQ scores have registered. Vocabulary: A wider gulf exists between Let’s take Raven’s and the various Wechsler parent and child as noted earlier. Seri- subtests (Table 32.1) one by one: ous writers have a larger adult audi- ence able to read their works, although Raven’s: Massive gains show that people the visual culture of our time may limit have freed logic from analyzing con- the number of those willing to do so. crete situations to deal with problems put abstractly. This has been a prereq- Another real-world implication of IQ uisite for the vast expansion of tertiary gains: Past standardization samples per- education and professional jobs requir- formed worse than recent ones, and set ing university skills and creative solu- lower norms. Therefore, obsolete IQ tests tion of problems on the spot (Schooler, give higher scores than up-to-date ones. 1998). Taking hypothetical situations Therefore, someone who took an obsolete seriously may have rendered moral and test may get 74 when his or her IQ on cur- political debate more reflective. The rent norms would be 69. Since a score of 70 is full potential of this has not been real- the cutting line for immunity from the death ized because even the best universities penalty in America, obsolete tests have lit- do not give their graduates the tools erally cost lives (Flynn, 2009b). they need to analyze the modern world except perhaps in their area of special- ization (Flynn, under review-a). Measurement Versus History Similarities: The huge gains mark a tran- sition from regarding the world as The phenomenon of IQ gains has created something to be manipulated for use unnecessary controversy because of con- to classifying it using the vocabulary ceptual confusion. Imagine an archaeolo- of science. This habit of mind is also a gist from the distant future who exca- prerequisite for higher education. vates our civilization and finds a record 658 JAMES R. FLYNN of performances over time on measures of Any confusion about the two roles has marksmanship. The test is always the same, been dispelled. If the battlefields had been that is, how many bullets you can put in a the artifacts first discovered, there would target 100 meters away in a minute. Records have been no confusion because no one from 1865 (the U.S. Civil War) show the uses battlefields as instruments for measur- best scoring as 5, records from 1898 (Spanish- ing marksmanship. It was the fact that the American War) show 10, while records from first artifacts were also instruments of mea- 1918 (World War I) show 50. surement that put historians and metricians A group of “marksmanship-metricians” at cross-purposes. Now they see that dif- looks at these data. They find it worthless ferent concepts dominate their two spheres: for measuring marksmanship. They make social evolution in weaponry – whose signif- two points. First, they distinguish between icance is that we have become much better the measure and the trait being measured. at solving the problem of how to kill people The mere fact that performance on the test quickly; marksmanship – whose significance has risen in terms of “items” correct does is determining which people have the abil- not mean that marksmanship ability has ity to kill more skillfully than other people increased. All we know is that the test has can. The metrician would not deny that the gotten easier. Many things might account historian’s account is important. The histo- for that. Second, they stress that we have rian has done nothing to undermine what only relative and no absolute scales of mea- the metrician does. Results on his tests have surement. We can rank soldiers against one great external validity. They tell us who is another at each of the three times. But likelytobepromotedineachofthethree we have no measure that would bridge the wars (insofar as marksmanship is a crite- transition from one shooting instrument to rion) and which of two armies equal in other another. How could you rank the best shot respects is likely to win a battle (the one with with a rifle against the best shot with a bow the best marksmen). and arrow? At this point, the marksmanship- I hope this analogy will convince psycho- metrician either gives up or looks for some- metricans (whose job it is to measure cog- thing that would allow him to do his job, nitive skill differences between people) that perhaps some new data that would afford my interpretation of the significance of IQ an absolute measure of marksmanship over gains over time is not adversarial. Let me time. make its import explicit. However, a group of military historians Some years ago, acting as an archaeolo- are also present and it is at this point they gist, I amassed a large body of data showing get excited. They want to know why the that IQ tests had gotten much easier over test got easier, irrespective of whether the the 20th century in America and elsewhere. answer aids or undermines the measure- Over the century, the average person was ment of marksmanship over time. They ask getting many more items correct on tests like the archaeologists to look further. If they Raven’s and Similarities. The response of are lucky, battlefields specific to each time intelligence- or g-metricians was dual: first, will be discovered. The 1865 battlefields dis- to distinguish IQ tests as measuring instru- close the presence of primitive rifles, the ments from the trait being measured, that is, 1898 ones, repeating rifles, and the 1918 ones, from intelligence or g (if you will); second, machine guns. Now we know why it was to note that in the absence of an absolute easier to get more bullets into the target over scale of measurement, the mere fact that the time and we can confirm that this was no tests had gotten easier told us nothing about measure of enhanced marksmanship. But it whether the trait was being enhanced. The was of enormous historical and social sig- difficulty was inherent. IQ tests were only nificance: Battle casualties, the industries relative scales of measurement ranking the needed to arm the troops, and so forth members of a group in terms of items they altered dramatically. found easy to items they found difficult. A SECULAR CHANGES IN INTELLIGENCE 659 radical shift in the ease/difficulty of items from those who believe they have discov- meant all bets were off. At this point, the g- ered better measures. No one denies that metrician decides that he cannot do his job g-loaded IQ tests are useful predictors of of measurement and begins to look for an things like academic achievement and life absolute measure that would allow him to outcomes like employment or obedience do so. to the law, and whether children are born However, as a cognitive historian, this in or out of wedlock. However, Sternberg was where I began to get excited: Why had has developed tests that measure creativity the items gotten so much easier over time? and practical intelligence as well the ana- Where was the alteration in our mental lytic skills emphasized in school, and these weaponry that was analogous to the transi- may give even better predictions of univer- tion from the rifle to the machine gun? This sity marks and job performance (Sternberg, meant returning to the role of archaeologist 1988, 2006; Sternberg et al., 2000). Heck- and finding battlefields of the mind that dis- man has developed research designs that tinguished 1900 from the year 2000.Ifound indicate that noncognitive traits are at least evidence of a profound shift from an exclu- as influential as cognitive traits (Heckman sively utilitarian attitude to concrete reality & Rubenstein, 2001; Heckman, Stixrud, & toward a much more abstract attitude – to Urzua, 2006). assuming that it was important to classify I have used an analogy to break the steel concrete reality in abstract terms (the more chain of ideas that circumscribed our abil- abstract the better); and that taking hypo- ity to see the light IQ gains shed on cog- thetical situations seriously had freed logic nitive history. But an analogy that clarifies to deal with not only hypothetical questions one thing can introduce a new confusion. but also with symbols that had no concrete The reciprocal causation between develop- referents. ing new weapons and the physique of marks- It was the initial artifacts that caused men is a shadow of the interaction between all the trouble. Because they were perfor- developing new habits of mind and the mances on IQ tests, and IQ tests are instru- brain. ments of measurement, the roles of the cog- The new weapons were a technological nitive historian and the g-metrician were development of something outside ourselves confused. Finding the causes and develop- that had minimal impact on biology: Per- ing the implications of a shift in habits of haps our trigger fingers got slightly different mind over time is simply not equivalent to exercise when we fired a machinegun rather a task of measurement, even the measure- than a musket. But the evolution from pre- ment of intelligence. Now all should see that occupation with the concrete and the literal different concepts dominate two spheres: to the abstract and hypothetical was a pro- society’s demands – whose evolution from found change within our minds that involved one generation to the next dominates the new problem-solving activities. Reciprocal realm of cognitive history; and g –which causation between mind and brain entails measures individual differences in cognitive that our brains may well be different from ability. And just as the g-metrician should those of our ancestors. It is a matter of use not undervalue the nonmeasurement task and structure. of the historian, so the historian does noth- If people switch from swimming to ing to devalue the measurement of which weight lifting, the new exercise develops individuals are most likely to learn fastest different muscles and the enhanced mus- and best when in competition with one cles make them better at the new activ- another. ity. Everything we know about the brain The direct challenge to those who use suggests that it is similar to our muscles. conventional IQ tests or the g derived Maguire et al. (2000) found that the brains of from them to measure individual differ- the best and most experienced London taxi- ences comes not from cognitive history but drivers were peculiar. They had an enlarged 660 JAMES R. FLYNN hippocampus, which is the brain area The Theory of Intelligence used for navigating three-dimensional space. Here we see one area of the brain being The thesis about psychometics and cogni- developed without comparable develop- tive history – that they actually complement ment of other areas in response to a spe- one another – and the remarks made about cialized cognitive activity. It may well be the brain imply a new approach to the the- that when we do “Raven’s-type” problems, ory of intelligence. I believe we need a BIDS certain centers of our brain are active that approach: one that treats the brain (B), indi- used to get little exercise; or it may be that vidual differences (ID), and social trends (S) we increase the efficiency of synaptic con- as three distinct levels, each having equal nections throughout the brain. If we could integrity. The three are interrelated and each scan the brains of people in 1900, who knows has the right to propose hypotheses about what differences we would see? what ought to happen on another level. It So if we can say that the marksman today is our job to investigate them independently shoots a superior gun to that of his prede- and then integrate what they tell us into a cessors, can we not say we have a superior coherent whole. brain to that of our ancestors? Not superior The core of a BIDS approach is that each in every way, of course. The machine gun’s of those levels has its own organizing con- gain in firepower is bought at the price of cept and it is a mistake to impose the archi- less maneuverability: If someone approaches tectonic concept of one level on another. you from the rear, you would do better to The best analogy I can find from the his- have a rifle that you can turn around in an tory of science is the controversy between instant. Our brain may have lost something Huygens, who championed the wave theory our ancestors had – something like the won- of light, and Newton, who held that light derful mapping system that Australian Abo- was a stream of corpuscles (particles). Much rigines use in the outback. But, even grant- time was wasted before someone realized ing that each generation has a brain adapted that light could act like a wave in certain of to the society of its day, do not our brains its manifestations and like a stream of par- deal with an environment of greater cogni- ticles in other manifestations. We have to tive complexity than in 1900?Andisthat realize that intelligence can act like a highly not sufficient reason to say that we are more correlated set of abilities on one level (indi- intelligent? vidual differences), like a set of functionally We can now resolve the question asked at independent abilities on another level (cog- the beginning: Do the huge IQ gains of the nitive trends over time), and like a mix on a 20th century mean we are more intelligent third level (the brain), whose structure and than our ancestors? If the question is, Do operations underlie what people do on both we have better brain potential at concep- of the other two levels. Let us look at the tion or were our ancestors too stupid to deal levels and their organizing concepts. with the concrete world of everyday life, the Individual differences. Performance differ- answer is no. If the question is, Do we live in ences between individuals on a wide variety a time that poses a wider range of cognitive of cognitive tasks are correlated primarily problems than those our ancestors encoun- in terms of the cognitive complexity of the tered, and have we developed new cognitive task (fluid g) – or the posited cognitive com- skills and the kind of brain that can deal with plexity of the path toward mastery (crystal- them, the answer is yes. Once we under- lized g). Information may not seem to dif- stand what has happened, we can commu- ferentiate individuals for intelligence, but if nicate with one another, even if some prefer two people have the same opportunity, the the label “more intelligent” and others pre- better mind is likely to accumulate a wider fer “different.” To care passionately about range of information. I will call the appro- which label we use is to surrender to the priate organizing concept “General Intelli- tyranny of words. gence” or g, without intending to foreclose SECULAR CHANGES IN INTELLIGENCE 661 improved measures that go beyond the lim- operations, that is, it is divided into match- itations of “academic” intelligence. ing CL, LL, PI, and VI sectors. Through Society. Various real-world cognitive skills magnetic resonance imaging scans (MRI) show different trends over time as a result of of the brain, we have “pictures” of these shifting social priorities. I will call this con- sectors. For example, somehow we have cept “Social Adaptation.” As I have argued, MRIs from 1900 that we can compare to the major confusion thus far has been either MRIs of 2000. When we measure the con- to insist on using the organizing concept of nections between neurons within the CL the individual differences level to assess cog- and LL sectors, we find that the later nitive evolution, and call IQ gains “hollow” brains have thicker connections, and that if they are not g gains; or to insist on using the extra thickness exactly predicts the cen- the organizing concept of the societal level tury’s enhanced performance on Similarities to characterize the measurement of individ- and Raven’s. ual differences in intelligence, and to deny As for individual differences, we have that some individuals really do have better equally informative pictures of what is going minds and brains to deal with the dominant on in the brains of two people in the VI sec- cognitive demands of their time. tor as they enjoy the same exposure to new The brain. Localized neural clusters are vocabulary. We note that the neurons (and developed differently as a result of spe- connections between neurons) of one person cialized cognitive exercise. There are also are better nourished than those of the other important factors that affect all neural clus- due to optimal blood supply (we know just ters such as blood supply, dopamine as a what the optimum is). We note that when substance that render synapses receptive to the neurons are used to learn new vocab- registering experience, and the input of the ulary, the connections between the neurons stress-response system. Let us call its orga- of one person are sprayed with the optimum nizing concept “Neural Federalism.” The amount of dopamine and the connections of brain is a system in which a certain degree the other are less adequately sprayed. And of autonomy is limited by a “higher” organi- we can measure the exact amount of extra zational structure. thickening of the connections the first per- Here I will linger a bit because researchers son enjoys compared to the second. All of on this level have the difficult task of this allows us to actually predict their differ- explaining what occurs on both of the other ent performances on the WISC Vocabulary two levels. The task of the brain physiolo- subtest. gist is reductionist. To illustrate, assume that Given all of the above, brain physiology physiologists have almost perfect knowledge would have performed its reductionist task: of the brain: When supplied with data on It would have reduced problem-solving dif- how cognition varies from person to per- ferences between individuals and between son and from time to time, they can map generations to brain functions; and it would exactly what brain “locations” underlie the have accommodated both the tendency of social and life histories supplied. To flesh various cognitive skills to be correlated on this out, make the simplifying assumption the individual differences level, and their that the mind performs only four operations tendency to show functional autonomy on when cognizing: classification or CL (of the the societal level. Similarities sort); liberated logic or LL (of the Raven’s sort); practical intelligence or PI (needed to manipulate the concrete world); Our Ancestors and Ourselves and vocabulary and information acquisition or VI. IQ trends over time have opened our eyes to We will posit that the brain is neatly a great romance: the cognitive history of the divided into four sectors active respectively 20th century. Science altered our lives and when the mind performs the four mental then liberated our minds from the concrete. 662 JAMES R. FLYNN

This history has not been written because, as that people sought cognitive stimulation children of our time, we do not perceive the from leisure. It meant that parents had to gulf that separates us from our distant ances- rear fewer children and they became preoc- tors: the difference between their world and cupied with affording their children a cog- the world seen through scientific spectacles. nitively stimulating environment. Schools Moreover, because the ability to cope with became filled with children and teachers the concrete demands of everyday life has less friendly to rote learning, and the world not been much enhanced, our distant ances- of work offered more and more profes- tors appear fully human. People use their sional and managerial jobs. These jobs both minds to adapt to the demands of their social required and stimulated the new habits of environment. Long before the beginning of mind. As this last implies, there was causal the 20th century, people felt a strong need interaction: New problems developed new to be cognitively self-sufficient in everyday skills and better skills allowed us to cope life and long before 1900, virtually everyone with an even wider range of problems. who could meet the demands of everyday The expanded population of secondary life had done so. The small percentage that school graduates was a prerequisite for the cannot (those who are genuinely mentally educational advance of the post-1950 era, retarded) has not varied much over the last that is, the huge increase in the num- 100 years. ber of university graduates. These gradu- Before 1900, most Americans had a few ates have gone the farthest toward view- years of school and then worked long hours ing the world through scientific spectacles. in factories, shops, or agriculture. Kinship They are more likely to be innovative and and church provided identity. Slowly soci- independent and therefore, can meet pro- ety began to demand that the mass of people fessional and managerial demands. A greater come to terms with the cognitive demands pool of those suited by temperament to be of secondary education, and contrary to the mathematicians or theoretical scientists or confident predictions of the privileged, they even philosophers, more contact with peo- met that challenge to a large degree. Mass ple who enjoy playing with ideas for its graduation from secondary school had pro- own sake, the improvement of managerial found real-world effects. The search for efficiency, the enhancement of leisure, the identity became a more individual quest. enhancement of moral and political debate – Education created a mass clientele for books, these things are not to be despised. plays, and the arts, and culture was enriched by contributions from those whose talents had hitherto gone undeveloped. Quo Vadis After 1950, the emergence of a new visual culture and perhaps a resistance to the Lynn and Vanhanen (2002) have engendered ever increased demands of classroom sub- pessimism by showing that the mean IQs of jects brought progress to an end in areas many nations in the developing world are like school mathematics and the apprecia- well below those in the developed world. tion of serious literature. Nonetheless, post- However, there are signs that IQ gains may 1950 IQ cognitive gains have been significant. cease in developed nations in the 21st cen- More and more people continued to put tury and evidence that they are just taking on scientific spectacles. As use of logic and off in the developing world. These trends the hypothetical moved beyond the con- would close the developed/developing IQ crete, people developed new habits of mind. gap and falsify the hypothesis that some The scientific ethos provided the prerequi- nations lack the intelligence to industrial- sites for this advance. However, once minds ize. In 1917, Americans had a mean IQ of were prepared to attack these new prob- 70 (against today’s norms), which matches lems, certain social triggers enhanced per- the lowest IQs found in the developing formance greatly. Post-1950 affluence meant world. IQ does not leap from 70 to 100 as a SECULAR CHANGES IN INTELLIGENCE 663 prerequisite for industrial development. The Colom, R., Lluis Font, J. M., & Andres-Pueyo, first step toward modernity raises IQ a bit, A. (2005). The generational intelligence gains which paves the way for the next step, are caused by decreasing variance in the lower which raises IQ a bit more, and so on. The half of the distribution: Supporting evidence 2005 converging IQ trends may be fragile: An for the nutrition hypothesis. Intelligence, , 33 83 92 environmental crisis might merely incon- , – . Daley, T. C., Whaley, S. E., Sigman, M. D., venience rich nations while sending poor Espinosa, M. P., & Neumann, C. (2003). IQ nations into a downward spiral toward star- on the rise: The Flynn effect in rural Kenyan vation and anarchy. children. Psychological Science, 14, 215–219. Despite static IQ, the developed world Emanuelsson, I., Reuterberg, S.-E., & Svens- may enjoy a century of cognitive progress son, A. (1993). Changing differences in intel- just as exciting as the last 100 years. Sci- ligence? Comparisons between groups of ence has not only freed logic from the con- thirteen-year-olds tested from 1960 to 1990. crete but has also bestowed a second gift, Scandinavian Journal of Educational Research, one on which we have not yet capitalized. 37, 259–277. 1984 I refer to a set of wonderful concepts that Flynn, J. R. ( ). The mean IQ of Americans: 1932 1978 allow us to critically analyze the modern Massive gains to . Psychological Bul- letin, 95, 29–51. world: market analysis, basic social science Flynn, J. R. (1987). Massive IQ gains in 14 nations: methodology, analytic concepts that make What IQ tests really measure. Psychological sense of international relations, philosoph- Bulletin, 101, 171–191. ical progress toward identifying bad argu- Flynn, J. R. (2009a). Requiem for nutrition as the ment particularly in ethics, and so forth. But cause of IQ gains: Raven’s gains in Britain 1938 there is no reason for optimism. Universities to 2008. Economics and Human Biology, 7, 18– seem determined to give each graduate one 27. or two of these tools at best. In the larger Flynn, J. R. (2009b). The WAIS-III and WAIS-IV: society, uncritical minds use logic and the Daubert motions favor the certainly false over vocabulary of science to argue for nonsense the approximately true. Applied Neuropsychol- 16 1 7 (creation science) and fill the schools with ogy, , – . Flynn, J. R. (2009c). What is intelligence? Beyond confusion. Even universities have become a the Flynn Effect. Expanded paperback edition. home to academics that kill critical acumen: New York, NY: Cambridge University Press. those who deny science and reason any spe- Flynn, J. R. (under review-a). How to improve your cial role in the search for truth. mind. IQ gains over time signal the evolution Flynn, J. R. (under review-b). The vocabularies of minds that can be better educated. 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