RL: In 1972 I moved to Ulster and began my work on national and racial differences in intelligence. I began publishing papers on this in 1977 when I estimated the mean IQ in Japan at 106.6 (in relation to an American mean of 100), and the mean IQ of the Chinese in Singapore at 110.
The next year I published a review of national and racial IQs. I continued to collect IQs for countries all over the world. I concluded that with the IQ of Europeans set at 100, the North East Asians have an IQ of 106, the South East Asians have an IQ of 90, the Native American Indians have an IQ of 89, and sub-Saharan Africans have an IQ around 70.
In 1980 I published my theory that these race differences evolved when early humans migrated out of Africa into temperate and then into cold environments. These were more cognitively demanding, and so the peoples who settled in North Africa and South Asia, and even more the Europeans and the North East Asians, had to evolve higher IQs to survive.
RL: Yes, Tatu Vanhanen is a political scientist in Finland and has a good knowledge of economics. We got in touch in 2000, met in London and talked about using my national IQs to explain the huge differences in living standards between the economically developed countries and the third world.
We found that the correlation between national IQs and per capita income was r = 0.68, so national IQs explained about half the variance in per capita income. The other half can be largely explained by the degree to which nations have free market economies and natural resources.
HN: How was the book received?
RL: It had the usual reaction to which I have become accustomed. Some hated it, some loved it. Among those who hated it was Earl Hunt, who described the national IQs as “meaningless”, while Susan Barnett and Wendy Williams said they were “virtually meaningless”.
Others saw my national IQs as opening up a new field in which national differences in intelligence have explanatory power for a wide range of social and economic phenomena. In 2009, Heiner Rindermann and Steve Ceci described the calculation of national IQs as
“... a new development in the study of cognitive ability: Following a century of conceptual and psychometric development in which individual and group (socioeconomic, age, and ethnic) differences were examined, researchers have turned their attention to national and international differences in cognitive competence to predict a variety of outcomes: societal development, rate of democratization, population health, productivity, gross domestic product (GDP), crime, health and longevity, infant mortality, and wage inequality”.From 2005, numerous papers have been published on a variety of correlates of national IQs.
In 2010, in collaboration with Gerhard Meisenberg, I integrated all the international studies of scores in reading comprehension, math and science understanding. We put this on a common metric for 108 nations and showed that they are perfectly correlated (r = 1.0) with national IQs. I doubt whether there is anyone who now disputes that my national IQs are valid.
HN: In 2005, you wrote another book on race differences in intelligence, The Global Bell Curve?
RL: This took as its starting point The Bell Curve, in which Richard Herrnstein and Charles Murray in 1994 showed in that in the United States there is a racial hierarchy in which Europeans have the highest IQ and perform best for earnings, socioeconomic status and a range of social phenomena, Hispanics come next, while Blacks do least well.
In The Global Bell Curve, I examined whether similar racial intelligence and socio-economic hierarchies are present in other parts of the world, and documented that they are. They are found in Europe, Africa, Latin America, the Caribbean, Southeast Asia, Australia and New Zealand.
It is invariably the Europeans and North East Asians who are at the top of these racial hierarchies. These are followed by the brown-skinned peoples who occupy intermediate positions, e.g. the Coloureds and Indians from the sub-continent in Africa, the Mulattos and Mestizos in Latin America, Indians in Europe, and light-skinned Blacks in the United States, who come in the middle of the IQ and socio-economic hierarchies, while the dark-skinned African Blacks and Native American Indians invariably come at the bottom of the hierarchies.
In Australia and New Zealand, it is the lighter-skinned Europeans and Chinese who are at the top of the IQ and socioeconomic hierarchies, while the darker-skinned Aborigines and Maoris are at the bottom. In South-East Asia in Singapore, Indonesia, the Philippines, Malaysia, and Thailand, it is invariably the Chinese who have higher IQs than the indigenous peoples and outperform them in education, earnings, wealth and socioeconomic status.
These colour-related social hierarchies are so inescapable that sociologists and anthropologists have coined the term pigmentocracy to describe them. A pigmentocracy is a society in which wealth and social status are related to skin colour. I argued that intelligence differences provide the best explanation for the racial hierarchies that are consistently present in all multiracial societies.
HN: I would like to turn now to your work on the increases in intelligence that occurred during the twentieth century.
RL: My first work on this appeared in 1982, when I published a paper showing that the IQ in Japan had increased by 7 IQ points from those born in 1910 to those born in 1969. I have published several more papers on the increase of IQs.
My last one in 2009 showed that in Britain it has recently come to an end among children aged 13 years and older, although it is still present in younger children. I have also considered the problem of why IQs have increased and published a paper in 1990 arguing that improvements in nutrition have been the main factor responsible for the IQ rise.
HN: You have also worked on sex differences in intelligence. How did this come about?
RL: In all fields of scholarship we have to take a lot on trust. If all previous scholars are agreed on something, we take it for granted that they must be right. All the experts from at least World War 1 had stated that there is no sex difference in intelligence. In the following years numerous scholars whom I respected repeated this assertion. For instance, Herrnstein and Murray wrote in The Bell Curve that “The consistent story has been that men and women have nearly identical IQs”.
I had no reason to doubt this consensus, but in 1992 I was shaken when Dave Ankneyand Phil Rushton independently published papers showing that men have larger brains than women, even when these are controlled for body size and weight.
It was evident that these results presented a problem. It is well established that brain size is positively related to intelligence at a correlation of about 0.4. As men have larger brains than women, men should have a higher average IQ than women. Yet all the experts were agreed that males and females have the same intelligence.
I grappled with this problem for about six months. I went through dozens of studies and the experts seemed to be right that males and females have the same intelligence. Then at last I found the solution.
When I looked at the studies in relation to the age of the samples being tested, I found that males and females do have the same intelligence up to the age of 15 years, as everyone had said.
But I found that from the age of 16 years onwards, males begin to show higher IQs than females and that by adulthood, the male advantage reaches about 5 IQ points, entirely consistent with their larger average brain size. I published this solution to what I called the Ankney-Rushton anomaly in 1994.
HN: And how was your solution received?
RL: Most people ignored it, including Art Jensen in his 1998 book The g Factor. He concluded that “the sex difference in psychometric g is either totally nonexistent or is of uncertain direction and of inconsequential magnitude”.
I continued to publish papers showing that, up to the age of 15 years, males and females have approximately the same IQ, except for a small male advantage on the visualization abilities, but from the age of 16 years males begin to show greater intelligence. But most people continued to assert that men and women have equal intelligence.
In 2006, Stephen Ceci and Wendy Williams published an edited book Why aren’t more women in Science? They brought together fifteen 15 experts to discuss this question. They began by saying “We have chosen to include all points of view”, but remarkably none of the contributors presented the case that men have higher intelligence than women, and that high intelligence is required to make a successful career in science. Several of the contributors asserted that there are no sex differences in intelligence.
The only person who attacked my theory was Nick Mackintosh. In 1996 he contended that the Progressive Matrices is an excellent measure of intelligence and of Spearman’s g, that it is known that there is no sex difference on the Progressive Matrices, and therefore that my claim is refuted. He made no mention of my maturation theory that it is only from the age of 16 years that males begin to show higher IQs than females.
In response to Mackintosh’s criticism, I collaborated with Paul Irwing in carrying out meta-analyses of sex differences on the Progressive Matrices in general population samples and in university students. We found that in general population samples, there is no sex difference up to the age of 15 years, but among adults, men have a higher IQ than women by 5 IQ points. Among university students, we found the male IQ advantage is 4.6 IQ points.
HN: Still, you did have some supporters for your theory that men have a higher average IQ than women. I myself came out in support of your theory.
RL: You did, and in the next few years several people published data supporting my theory, including Juri Allik, Doug Jackson and Phil Rushton, Roberto Colom, and Gerhard Meisenberg. By 2010, numerous studies had shown that men have a higher IQ than women. I believe this is now accepted by all serious scholars. But, of course, there are plenty of unserious scholars who have never bothered to read the literature on this issue.
HN: Let us move on to your work on eugenics.
RL: I became interested in eugenics when I was a student in the 1950s. I read the papers of several psychologists in the United States, and of Sir Cyril Burt, Sir Godfrey Thompson and Ray Cattell in Britain, showing that the average IQ of the population was declining because people with low IQs were having more children than those with high IQs. I thought this must be an enormously serious problem. But it was not until the early 1990s that I began to work on eugenics.
I have published several papers showing that dysgenic fertility for intelligence in the United States and Britain, and one showing that there is also dysgenic fertility for moral character. In 1996 I published Dysgenics: Genetic Deterioration in Modern Populations,which set out the evidence that modern populations have been deteriorating genetically from around 1880 in respect of health, intelligence and moral character.
In 2001, I published a sequel Eugenics: A Reassessment. This begins with a historical introduction giving an account of the ideas of Francis Galton and the rise and fall of eugenics in the 20th century. I then discuss the objectives of eugenics and identify these as the elimination of genetic diseases, and the improvement of intelligence and moral character.
This is followed by a consideration of how eugenic objectives can be achieved using the methods of selective reproduction and concludes that there is not much scope for these.
Finally, I discuss the how eugenic objectives could be achieved by the “New Eugenics” of biotechnology using embryo selection, and how these are likely to be developed in the twenty-first century. I conclude by predicting the inevitability of a future eugenic world in which couples will select genetically-desirable embryos for implantation, and that there will be huge improvements in the genetic quality of the populations of economically developed countries where these technologies are adopted.
I have continued to publish papers on genetic deterioration. I extended this in a study with John Harvey to an estimate of the decline of the world’s IQ caused by the high fertility in third world low IQ countries. We estimated that the world’s IQ deteriorated genetically by 0.86 IQ points in the years 1950-2000.
HN: You have also published work on racial and ethnic differences in personality.
RL: Yes, in 2002 I took up the problem that Dick Herrnstein and Charles Murray noted in The Bell Curve, that while racial and ethnic differences in intelligence can explain a number of the differences in educational attainment, crime, welfare dependency, rates of marriage, etc., they cannot explain the totality of these differences.
They concluded that there must be some additional factor that also contributes to these.
I proposed that some of the residual disparities are attributable to differences in psychopathic personality. I showed that psychopathic personality is highest among Blacks and Native Americans, next highest in Hispanics, lower in Whites and lowest in East Asians.
RL: Some years ago, I read that about a third of the Nobel Prizes won by Germany in the years 1901-1939 had been awarded to Jews. I checked out the numbers of Jews in Germany and found they were about 0.85 per cent of the population.
I reflected that Jews must have had a high IQ to achieve this astonishing overrepresentation. I had a look at the research on the intelligence of the Jews and found that a number of studies had been published reporting that Jews do indeed have high IQs. These were all quite old.
Comparative studies of the IQs of different peoples have become increasingly taboo in recent decades. I investigated the Jewish IQ and estimated the Ashkenazi IQ at approximately 110, and the IQ of Oriental Jews at 91.
I also wondered whether the Jews might have some personality characteristic, such as a strong work ethic, which might contribute to their high achievements, but could not find any evidence for this in a paper published in 2008 with Satoshi Kanazawa.
I then read a number of papers in economics and sociology journals on the educational attainments, earnings and socioeconomic status of Jews in the United States, and found numerous studies, going back to the first half of the twentieth century, reporting that these are all higher in Jews than in Gentile whites.
But the strange thing is that none of these mentioned that the explanation for the remarkable achievements of the Jews could be that they are more intelligent than white gentiles.
The more of these papers I read, the more it became apparent that a job needed to be done investigating whether Jews have a high IQ and commensurate educational attainments, earnings and socio-economic status in all countries in which Jews are, or have been, present. I have documented that this has been so in my book The Chosen People: Jewish Intelligence and Achievements.
HN: I have one final question. How would you like to be remembered?
RL: I hope my obituarists will write something like “Some loved him, some hated him, but everyone accepted that he kept the faith and told the truth as he saw it”.