IQ and the Wealth of Nations: Richard Lynn Replies to Ron Unz

[See also Helmuth Nyborg’s Reply to Ron Unz and Has Ron Unz Refuted “Hard Hereditarianism”?]

Cross posted at American Renaissance

Ron Unz has made a number of criticisms of our work first published in IQ and the Wealth of Nations,in which Tatu Vanhanen and I presented IQs for all nations in the world. We showed that these are correlated at 0.50–0.75 with per capita income measured as GDP, and we argued that national IQs are a significant determinant of economic development.

I reply here to Unz’s criticisms.

The Direction of Causation

Unz begins by raising the issue of causation in the association between national IQ and per capita income association. He writes: “If high national IQ scores are correlated with economic success, perhaps the high IQs cause the success, but it seems just as possible that the success might be driving the high IQs, or that both might be due to some third factor.”

Unz attributes to us a position “which claims that the data demonstrate IQ is genetically fixed and determines which nations will be rich and which will be poor.” Later, he writes of “the IQ-makes-wealth hypothesis of Lynn and Vanhanen” as contrasted with “the contrary wealth-makes-IQ hypothesis of traditional liberals.” He adds that we should take into account “the possible impact of malnutrition and other forms of extreme deprivation”.

Lynn replies: Unz misunderstands our position. We do not propose that the IQs of individuals or of nations are genetically fixed. On the contrary, we are well aware that IQs have been increasing in many countries during the last 70 or so years and that these increases are a result of improvements in the environment, such as better nutrition and longer education. We propose a positive feedback relation from genetically based national IQs to per capita income, and from per capita income on national IQs.

We discuss the causal effect of per capita income on national IQs in IQ and the Wealth of Nations, in which we devote pages 185 to 189 to outlining how improvements in nutrition, health, and education would increase the IQs in low IQ countries. We make the same point in our later book, IQ and Global Inequality (2006), in which we write, “While we believe it is impossible to avoid the conclusion that genetic factors are partly responsible for the race differences in intelligence that underlie national differences, we also believe that environmental factors also contribute to the national differences in intelligence. Widespread sub-optimal nutrition and poor health undoubtedly impair the intelligence of populations of the poor nations. . . . we do not doubt that improvements in nutrition would increase intelligence in economically developing countries” (p. 244).

We repeat this point in our latest book, Intelligence: A Unifying Explanatory Construct for the Social Sciences (2012) in which we write, “differences in national IQs are based partly, although not entirely, on genetic differences between populations” (p. 354). Thus, we have consistently advanced a two-way causal model such that national IQs affect per capita income and per capita income affects national IQs.

Contrary to the position imputed to us that the IQs of nations are genetically fixed, more than 30 years ago I published data showing that the IQ in Japan has increased more rapidly than in the United States, and proposed that improvements in nutrition were one of the responsible factors (Lynn, 1977b, 1982). I have since published a number of further papers on the contribution of improvements in nutrition to secular increases of intelligence (Lynn, 1990, 1993, 1998, 2007, 2009).

IQ Differences in European Nations

Unz writes:

In order to minimize these extraneous factors, let us restrict our initial examination to the 60-odd IQ data points Lynn and Vanhanen obtained from European countries and their overseas offshoots over the last half-century. . . . What we immediately notice is a long list of enormous variations in the tested IQs of genetically indistinguishable European peoples across temporal, geographical, and political lines, variations so large as to raise severe doubts about the strongly genetic deterministic model of IQ favored by Lynn and Vanhanen. We also discover rather low IQ scores in all the reported samples of Greece’s impoverished Balkan neighbors in the Eastern Bloc taken before the collapse of Communism. Croatians scored 90 in 1952, two separate tests of Bulgarians in 1979–1982 put their IQs at 91–94, and Romanians scored 94 in 1972.

It seems more plausible that most of the large and consistent IQ gaps between Western Europeans and their Balkan cousins are less a cause than a consequenceof differences in development and affluence during the era in which these IQs were tested. [Race, IQ, and Wealth | What the facts tell us about a taboo subject, The American Conservative July 18, 2012]

Lynn replies: Intelligence tests are imperfect measuring instruments, so we should not expect that different tests administered in the same country to different and imperfectly representative samples, to different age groups, and at different times, would give exactly the same results. Two different IQ tests given to an individual typically give different IQs, and are typically correlated at about 0.7. This is due to imperfect reliability, measurement errors, sampling differences, and because different tests measure different abilities such as verbal comprehension, non-verbal reasoning, spatial and drawing abilities, etc., and therefore give different IQs.

In our list of more than 400 national IQs, there are inevitably some cases where some IQs for a country differ quite considerably, just as there will be other cases where there is very little difference. For instance, our four IQs for Canada range between 97 and 100, our four IQs for Indonesia range between 87 and 88, and our three IQs for Switzerland range between 101 and 104.

To overcome the problem of the variation of results in some countries, we have taken for each country the median of a number of IQs. This largely removes the problem of anomalous results.

Croatia and Austria

Unz notes that “the borders of Austria and Croatia are just a couple of dozen miles apart, both are Catholic countries that spent centuries as part of the Austro-Hungarian Empire, and it is quite difficult to distinguish Austrians from Croatians either by appearance or by genetic testing. Yet the gap between their reported IQ scores—12 points—is nearly as wide as that separating American blacks and whites.”

Lynn replies: It is a pity that here and throughout his critique Unz uses our limited ten-year-old national IQ data given in our first (2002) book and not our much more extensive recent data given in Meisenberg & Lynn (2011) and in our latest 2012 book which gives many more national IQs and therefore more accurate results. In our 2012 book we give 3 IQ studies for Croatia and estimate the IQ at 97.8 and two studies for Austria with a mean of 99.0. Thus, there is a slight drop of 1.2 IQ points from Austria to Croatia in the north part of the Balkans, as our theory predicts. If Unz had looked at our most recent data the problem he raises for Croatia and Austria would disappear, and the same is true of many of the other problems he raises.

Genetic Distinctions of European Peoples

Unz argues that “the European peoples are genetically indistinguishable,” and therefore that the IQ differences between them must be environmentally determined.

Lynn replies: Unz is incorrect in his assertion that all the European peoples are genetically indistinguishable. In fact he contradicts himself on this point as he also writes that “although Greeks and Turks have a bitter history of ethnic and political conflict, modern studies have found them to be genetically almost indistinguishable.” Unz is correct that Greeks and Turks are genetically similar, as shown by Cavalli-Sforza, Menozzi & Piazza  (1996, p.268).  

However, it is not correct to assert that “all the European peoples are genetically indistinguishable.” Classical anthropologists identified seven genetically distinguishable European races. These are the blue-eyed and fair-haired Nordics in northern Europe, the Alpines in central Europe, the East Baltics in Russia, the Mediterraneans—a darker skinned and brown eyed people in southern Europe—Celts in the west of Ireland and Brittany, Dinarics in the former Yugoslavia and south Poland, and Basques in southwest France. Genetic differences between European peoples confirming the classical taxonomy are given by Cavalli-Sforza, Menozzi & Piazza (1996, p.268). More extensive data for differences in the frequencies of 14 haplogroups in Europe and the Middle East and their association with IQs are given by Rindermann, Woodley & Stratford (2012).

Among the Mediterranean peoples, there is a genetic distinction between those in the southern Balkans, southern Italy and southern Spain, and those in the more northerly latitudes. It has been shown in numerous genetic studies that all the populations in the southern European latitudes are a genetic mix of European and Middle Eastern peoples. For example, the Taql, p1 2f2-8-kb allele has a frequency of between 28.3 and 43.7 percent in the Near East and North Africa, of 27.3 per cent in Greece, 20.8 per cent in Albania and 26.4 per cent in southern Italy, in all of which there was considerable immigration from the Near East and North Africa in pre-historic and historical times. The frequency of the allele drops to 14.1 percent in North Italy, 5.9 percent in the south of Spain and only 1.7 per cent in the north. The allele has a low frequency in central Europe represented by France (3.8 percent) and the Netherlands (3.5 percent). There are similar population differences in the Y-chromosome haplogroup E (Hg E) in the Near East and North Africa, Italy, southern and northern Spain, and Central Europe, given in Lynn (2012b).

These genetic differences explain why IQs in the Balkans, southern Italy, and southern Spain are in the range of 89 to 95 and therefore intermediate between approximately 99 for central and north western Europe and approximately 84 for the Middle East (Lynn, 2010a; 2010b; 2012a; 2012b).

Immigrants in the United States

Unz states that immigrants from the Balkans into the United States are:

considerably above most other American whites in both family income and educational level,” and he argues that this shows that the Balkan peoples have the same or higher IQs as central and north west Europeans: “If these differences of perhaps 10 or even 15 IQ points between impoverished Balkan Europeans and wealthyWestern ones reflected deeply hereditary rather than transitory environmental influences, they surely would have maintained themselves when these groups immigrated to the United States. But there is no evidence of this. As it happens, Americans of Greek and South Slav origins are considerably above most other American whites in both family income and educational level. Since the overwhelming majority of the latter trace their ancestry to Britain and other high IQ countries of Western Europe, this would seem a strange result if the Balkan peoples truly did suffer from an innate ability deficit approaching a full standard deviation.

Lynn replies: Unz exaggerates when he asserts that people in the Balkans differ by perhaps 10 or even 15 IQ points from central and northern Europeans. The average IQ in the Balkans given in our 2012 book is 92, and therefore about 7 IQ points lower than that in central and northern Europe.

Unz also exaggerates when he asserts that immigrants of Greek and South Slav origins are considerably above most other American whites in family income. The average annual earnings ($US in thousands) of men aged 25-54 in the United States in 1979 were Austrians 29.4, Belgians 27.2, Danes 25.4. English 24.1, Finns 27.3, Germans 24.4, Greeks 25.7, Irish 24.5, Scottish 25.7, Scots-Irish 25.4, Yugoslavs 28.0 and Welsh 25.7. Thus, the income of Greeks and Yugoslavs in the United States is about the same as that of north and central Europeans, and not considerably higher as Unz asserts. These figures are given in the census of 1980 and are available in the Bureau of the Census Public Use Microdata sample.

That the incomes of Greeks and Yugoslavs in the United States should be about the same as those of northern and central Europeans is probably attributable to selective emigration from the Balkans. Typically, when people emigrate from poor regions to more affluent regions, migrants tend to have higher than average IQs. The reason for this is that a higher IQ is needed to envision the advantages and to plan and find the resources to migrate. This has been shown in the United States by Vigdor (2002), who has found that it was blacks with greater educational attainment (a proxy for intelligence) who migrated from the southern states to the northern states, with the result that blacks in the northern states have an IQ about 10 points higher than those in the South. Kaufman & Doppelt (1976) report an average IQ of 90.5 for blacks in the northern states compared with approximately 85 for all American blacks, and around 80 for those in the southern states. Further evidence that migration is typically selective for intelligence is available for Scotland, from a follow-up study of 1,000 11-year-olds whose IQs were tested in 1947. By the age of 30, 17.2 percent had emigrated, and they had had an average IQ of 108.1 (Lynn, 1977b).

North and South Italy

Unz writes:

Similar sharp differences occur in the case of Italian populations separated historically and geographically. Today, Italian-Americans are very close to the national white average in income and education, and the limited data we have seem to put their IQ close to this average as well. This would appear consistent with the IQ figures reported for Italy by Lynn and Vanhanen, which are based on large samples and come in at just above 100. However, there is a notoriously wide economic gap between northern Italy and the south, including Sicily. The overwhelming majority of Italian-Americans trace their ancestry to the latter, quite impoverished regions, and in 2010 Lynn reported new research indicating that the present-day IQ of Italians living in those areas was as low as 89, a figure that places them almost a full standard deviation below either their Northern Italian compatriots or their separated American cousins.  

Lynn replies: The only region in Italy where the IQ is as low as 89 is Sicily. In the other four regions of southern Italy the IQ lies between 90 and 92. These IQs in the range of 89-92 cannot be described as “almost a full standard deviation below their Northern Italian compatriots.” A full standard deviation is 15 IQ points, but the difference between the north and the south of Italy is two thirds of a standard deviation. This difference can be explained by selective emigration of the more intelligent from southern Italy. As noted above, the IQ of blacks whose forebears migrated to the northern states of United States is 10 points higher than that of those who remained in the southern states, and emigrants from Scotland had an IQ 8 points higher than those who remained in Scotland. Emigrants from the south of Italy probably similarly higher IQs.

Unz continues: “Although Lynn attributed this large deficit in Southern Italian IQ to substantial North African or Near Eastern genetic admixture, poverty and cultural deprivation seem more likely explanations.”

Lynn replies: Unz needs to explain why there has been poverty and cultural deprivation throughout the far south of Europe. The consistently low IQs in southern mainland Italy (IQ: 91), Sicily (IQ:89), Sardinia (IQ: 90), southern Spain (IQ: 94.4), the Balkans (IQ: 92), Malta (IQ: 95.3), Cyprus (IQ: 91.8) and Turkey (IQ: 89.4), and the high frequency of African and Middle Eastern genes in these locations make the genetic theory more plausible.

Israel and the Jews

Unz writes:

The Lynn/Vanhanen data on Jews also provide some suspicious IQ disparities. American Jews have among the highest tested IQs, with means being usually reported in the 110–115 range. Yet Lynn and Vanhanen report that Israeli Jews have strikingly low IQs by comparison. One large sample from 1989 put the figure at 90, while a far smaller sample from 1975 indicated an IQ of 97, with both results drawn from Israel’s large Jewish majority rather than its small Arab minority. The IQ gaps with American Jews are enormous, perhaps as large as 25 points, and difficult to explain by genetic factors, since a majority of Israel’s Jewish population in that period consisted of ethnic Askhenazi (European) Jews, just like those in America. The huge economic gulf between Israeli Jews, who then had less than half the average American per capita GDP, and American Jews, who were far above average in American income, would seem to be the most plausible explanation.  

Lynn replies: Unz would have found the answers to the questions he raises if he had consulted my book The Chosen People: A Study of Jewish Intelligence and Achievements (2011). In it I provide a considerable amount of information about the IQs of the Jews in different countries, and show that the average IQ of Askhenazi Jews in the United States based on 32 studies is 110, and the average IQ of Askhenazi Jews in Britain, Canada and Poland is also 110. My estimate of the IQ of European Jews in Israel is 106 and I discuss why this is lower than the IQ of 110 of European Jews in Britain, Canada, Poland and the United States. I propose that the explanation is that not all of those classified as European Jews in Israel are Ashkenazim. Of the 2.4 million classified in Israel as European Jews, approximately 1.4 million (58 per cent) are Ashkenazim. About 900,000 are Russians, many of whom are not Jewish or in some cases a half or a quarter Jewish, who claimed Jewish ethnicity in order to leave the Soviet Union. A further approximately 110,000 are Sephardim from the Balkans whose IQ is approximately 98. It is including these two groups that reduces the IQ of European Jews in Israel to 106.


Unz writes:

Perhaps the strongest evidence supporting this cultural rather than genetic hypothesis comes from the north western corner of Europe, namely Celtic Ireland. When the early waves of Catholic Irish immigrants reached America near the middle of the 19th century, they were widely seen as particularly ignorant and uncouth and aroused much hostility from commentators of the era, some of whom suggested that they might be innately deficient in both character and intelligence. But they advanced economically at a reasonable pace, and within less than a century had become wealthier and better educated than the average white American, including those of “Old Stock” ancestry.  

Lynn replies: Unz exaggerates. The average annual earnings ($US, thousands) of men aged 25-54 in the United States in 1979 have been given above and show that the average annual earnings of the Irish at 24.5 were about the same as others of “Old Stock” ancestry, e.g. English 24.1, Scottish 25.7, etc. 


Unz writes: “The evidence today is that the tested IQ of the typical Irish-American—to the extent it can be distinguished—is somewhat above the national white American average of around 100 and also above that of most German-Americans, who arrived around the same time”

Lynn replies: This is incorrect. The table below gives average IQs, calculated from g-factor scores, for seven ethnic groups in the United States. These data are from the NLSY79, for subjects aged 15-23 years, who were tested in 1980. The differences between the European groups are not statistically significant, and show that the typical Irish-American IQ is the same as the white American average.


Ethnic group

























Unz writes:

Meanwhile, Ireland itself remained largely rural and economically backward and during the 1970s and 1980s still possessed a real per capita GDP less than half that of the United States. Perhaps we should not be too surprised to discover that Lynn and Vanhanen list the Irish IQ at just 93 based on two samples taken during the 1970s, a figure far below that of their Irish-American cousins.

Even this rather low Irish IQ figure is quite misleading, since it was derived by averaging two separately reported Irish samples. The earlier of these, taken in 1972, involved nearly 3,500 Irish schoolchildren and is one of the largest European samples found anywhere in Lynn/Vanhanen, while the other, taken in 1979, involved just 75 Irish adults and is one of the smallest. The mean IQ of the large group was 87, while that of the tiny group was 98, and the Lynn/Vanhanen figure was obtained by combining these results through straight, unweighted averaging, which seems a doubtful approach. Indeed, a sample of 75 adults is so small it perhaps should simply be excluded on statistical grounds, given the high likelihood that it was drawn from a single location and is therefore unrepresentative of its nation as a whole.

So we are left with strong evidence that in the early 1970s, the Irish IQ averaged 87, the lowest figure anywhere in Europe and a full standard deviation below than that of Irish-Americans, a value which would seem to place a substantial fraction of Ireland’s population on the edge of clinical mental retardation.  

Lynn replies: Once again, it is a pity that Unz relies on our first study giving two IQs for Ireland rather than our latest compilation giving ten IQs for Ireland, from which we estimate an IQ of 95.

Unz writes:

Lynn’s late-1960s views regarding the mostly genetic cause of low Irish IQ seem unwarranted. Ireland was then overwhelmingly rural and poor, with a low per capita GDP, while Irish Americans tended to be an urban population and a reasonably affluent one, and this sharp difference in external material conditions seems the most logical explanation for the wide disparity in IQ results. In further support of this environmental hypothesis, we should note that it has been estimated that nearly one-third of Australia’s population is wholly or substantially Irish in ancestry, with the balance mostly British, while the IQ results Lynn and Vanhanen report for Australia are all very close to the British average of 100.  

Later in his article Unz considers the possibility of selective emigration from Ireland:

One might speculate that the smarter Irish immigrated to America, while their dimmer relatives remained at home, and the same was also true for the smarter Southern Italians, Greeks, or other Balkan Europeans. Similarly, perhaps the smarter European Jews crossed the oceans to New York Harbor in the years before World War I, while their dimmer relatives stayed behind and later moved to Israel after World War II.

These explanations seem quite unlikely. The intra-ethnic IQ gaps being discussed are absolutely enormous—often approaching a full standard deviation or more—and that would imply a similarly enormous gap between the portions of the population that stayed and those that emigrated, with no contemporaneous source seeming to provide any indication of this.  

Lynn replies: Unz exaggerates. There are no cases in which “the intra-ethnic IQ gaps being discussed are absolutely enormous—often approaching a full standard deviation or more.” In our latest compilation we give the IQ for Ireland as 95, and therefore 4 IQ points—less than one third of a standard deviation—lower than that in northern and central western Europe. The IQ gap for southern Italy is 10 IQ points, approximately two thirds of a standard deviation lower than that in northern and central western Europe.

Magnitude of Non-genetic Factors

Unz writes: “To a small extent, Lynn and Vanhanen acknowledge the possible importance of non-genetic factors, and they devote a few pages to a discussion of the impact of health, nutrition, and education on IQ scores. But they never provide any clear estimate for the magnitude of these influences.”

Lynn replies: In my book Race Differences in Intelligence (2006, p.70), I estimated that sub-Saharan Africans have a phenotypic IQ of 67 and a genotypic IQ of 80. Thus, I estimated that the adverse environment reduces their IQ by 13 IQ points and that genetic factors reduce their IQ by 20 IQ points, compared with Europeans. Thus, 43 percent of the low IQ in sub-Saharan Africa is attributable to adverse environments and the remaining 57 percent is attributable to genetic factors.


Unz writes:

Sharp critics of our heavy recent immigration from Mexico sometimes claim—or at least hint—that the intellectual weakness of these millions of newcomers may constitute a disastrous long-term burden to American society. On anonymous Internet forums such voices are often more explicit and directly cite Lynn and Vanhanen in placing the Mexican IQ at just 87, far below the white American average, and a worrisome indicator given that as much as one quarter of all Americans may be of Mexican ancestry by around the middle of this century.

The IQ figure of 87 that they quote from Lynn/Vanhanen is correct, though admittedly based on a single 1961 study of Mexican schoolchildren in the most impoverished southern part of that country.  

Lynn replies: In our 2012 book we give two more IQs of 88 for Mexico. This is almost identical to the IQ of 89 of Hispanics in the United States given by Roth et al. (2001) in a meta-analysis of a number of studies.

Unz writes:

Ron Guhname … decided to explore the Wordsum-implied IQ of American-born Mexican-Americans and discovered a remarkable result. These IQs were quite low, 84–85, in the 1970s and 1980s, a result consistent with the IQ samples reported by Lynn/Vanhanen for that era. But the Mexican-American IQ then jumped 7 points by the 1990s and an additional 3 points by the 2000s, a rise of 10 full points in just 20 years, while the Wordsum-implied IQ values for white Americans rose merely 2 points during that same period, presumably as an aspect of the regular Flynn Effect.

In actual values, the Mexican-American Wordsum-IQ increased from 84.4 in the 1980s to 95.1 in the 2000s, while the rise for American whites was from 99.2 to 101.3. In addition, the late 1990s IQ of U.S.-born Mexican-Americans has been separately estimated at 92.4 from the large data set contained in the National Longitudinal Survey of Youth (NLSY-97), a figure consistent with these Wordsum-IQ findings.

Thus, almost two-thirds of the IQ gap between American-born Mexican-Americans and whites disappeared in two decades, with these results being based on nationally-representative American samples of statistically significant size.  

Lynn replies: Contrary to these claims, there was no increase in the IQ of Hispanics relative to whites over the years 1986-2004 in a study by Ang, Rogers and Wanstrom (2010). However, I do not dispute that when people who do not speak English move from an impoverished country to the affluent United States, the IQs of their children increase a bit as a result of learning the English language and improved environmental conditions. Indeed I have documented as example of this in the early studies of Jews in the United States, when their IQs were about 100. It is only in the studies from the 1940s onwards that Jews obtain their average IQ of 110.

East Asians

Unz writes:

This strong relationship between wealth and nominal IQ seems to disappear when we examine East Asian populations. A few decades ago, China, Taiwan, Hong Kong, Singapore, South Korea, and even Japan had extremely low per capita GDPs relative to those of America or Europe, yet almost all their tested IQs were around 100 or higher, comparable to those of the wealthiest and most advanced European derived nations. In many cases, their incomes and standards of living were far below those of the impoverished nations of Southern and Eastern Europe, yet they showed no signs of the substantially depressed performance generally found in these latter countries, whose IQs were usually in the 88–94 range.

The most plausible inference from these decades of accumulated data is that the IQs of East Asian peoples tend to be more robust and insulated against the negative impact of cultural or economic deprivation than those of European groups or various others—a truly remarkable finding.

Unz concludes that the East Asians are an exception to his theory that depressed socio-economic conditions are responsible for the low IQs in southern Europe.

Lynn replies: The East Asians are indeed an anomaly for Unz’s environmentalist theory. The IQ in impoverished China is the same as that in affluent Taiwan, Singapore, Japan, and South Korea. But Unz is wrong in his assertion that the high IQs of the East Asians despite depressed socio-economic conditions are an exception. The same problem for Unz’s environmentalist theory is present in the IQs of western and eastern Europe, where communism depressed socio-economic conditions but IQs have been virtually identical to those of affluent western Europe. In our 2012 compilation we give a median IQ of 97.2 for ten former communist countries and a median IQ of 99 for 14 countries of northern and central western Europe. This negligible difference of 1.8 IQ points indicates that the depressed socio-economic conditions of eastern Europe had virtually no adverse impact on their national IQs.

The comparison of the IQs in eastern Europe with those in northern and central western Europe provide a quasi experiment to test Unz’s environmentalist theory. Take a group of ten nations in eastern Europe, subject them to communism for half a century, with the result that their standard of living is greatly reduced compared with that in the control group of 14 affluent countries of northern and central western Europe. Unz’s environmentalist theory predicts that the IQs in the nations in eastern Europe will be greatly impaired, while our genetic theory predicts that the adverse environment will have had little adverse effect on their IQs. The fact that the impoverished environment of communism has had virtually no adverse effect on he IQs in eastern Europe confirms our theory of the largely genetic determination of national IQs and is a serious anomaly for Unz’s environmentalist theory.

The IQ of 97.2 in eastern Europe is significantly higher than that in the Balkan nations that have also experienced depressed socio-economic conditions comparable to those in eastern Europe, but where the median IQ is 92. The most reasonable explanation for this is that the people of the Balkans are a mixed race European-Middle Eastern people who differ genetically from those of eastern and western Europe.  

The “Strong IQ Hypothesis”

Unz writes: “The central thesis of Lynn and Vanhanen’s work might be called the ‘Strong IQ Hypothesis,’ namely that IQ accurately reflects intelligence, that IQ is overwhelmingly determined by genetics, and that IQ is subject to little or no ignificant cultural or economic influence after we adjust for the universal Flynn Effect.”

Lynn replies: This is not a fair summary of our position. We have never maintained that IQ is overwhelmingly determined by genetics, or that IQ is subject to little or no significant cultural or economic influence.

Unz’s alternative environmentalist theory of IQ differences between the European peoples fails. He starts with the assumption that there are no genetic differences between the European peoples, and therefore that the IQ differences between them must be environmental. There is overwhelming evidence that this assumption is incorrect. There are considerable genetic differences between the European peoples such that North African and Middle Eastern genes are more common throughout the south, and this explains why the IQs throughout the south are substantially lower at around 92 than those in central and northern Europe.


An unsatisfactory feature of Unz’s article is that although he disagrees with our position that there is a significant genetic determination of national IQs and that these have an effect on per capita income, he has nothing to say about the national IQ-per capita income relation as a world-wide phenomenon.

He confines his discussion to IQ and per capita income differences in Europe, the IQ in Israel, and the IQs of Mexicans in the United States. These are minor parts of our work, in which we have shown an association between national IQs, race, and per capita income world wide and in Latin America, Africa, Asia, Australia and New Zealand. Perhaps Unz believes that in all these places environmental factors can explain the national and racial IQ differences, and that all races and nations have the same genetic IQ. Does he believe that sub-Saharan Africans (IQ: 67) and Australian Aborigines (IQ: 62) will achieve the same IQs and per capita incomes as Europeans in two or three generations? Readers of this exchange will no doubt look forward to seeing Unz’ answers to these questions. 


Richard Lynn [Email him] is Professor Emeritus, University of Ulster, and the author of several books on IQ, including The Global Bell Curve,    IQ and Global Inequality. and The Chosen People: A Study of Jewish Intelligence and Achievement, reviewed by Steve Sailer here.


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