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Is the human brain ‘special’? Not according to Herculano-Houzel; our brains are just linearly scaled-up primate brains. We have the number of neurons predicted for a primate of our body size. But what does this have to do with general intelligence? Evolutionary psychologists also contend that the human brain is not ‘special’; that it is an evolved organ just like the rest of our body. Satoshi Kanazawa (2003) proposed the ‘Savanna Hypothesis‘ which states that more intelligent people are better able to deal with ‘evolutionary novel’ situations (situations that we didn’t have to deal with in our ancestral African environment, for example) whereas he purports that general intelligence does not affect an individuals’ ability to deal with evolutionarily familiar entities and situations. I don’t really have a stance on it yet, though I do find it extremely interesting, with it making (intuitive) sense.
Kanazawa (2010) suggests that general intelligence may both be an evolved adaptation and an ‘individual-difference variable’. Evolutionary psychologists contend that evolved psychological adaptations are for the ancestral environment which was evolved in, not in any modern-day environment. Kanazawa (2010) writes:
The human brain has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment. Burnham and Johnson (2005, pp. 130–131) referred to the same observation as the evolutionary legacy hypothesis, whereas Hagen and Hammerstein (2006, pp. 341–343) called it the mismatch hypothesis.
From an evolutionary perspective, this does make sense. A perfect example is Eurasian societies vs. African ones. you can see the evolutionary novelty in Eurasian civilizations, while African societies are much closer (though obviously not fully) to our ancestral environment. Thusly, since the situations found in Africa are not evolutionarily novel, it does not take high levels of g to survive in, while Eurasian societies (which are evolutionarily novel) take much higher levels of g to live and survive in.
Kanazawa rightly states that most evolutionary psychologists and biologists contend that there have been no changes to the human brain in the last 10,000 years, in line with his Savanna Hypothesis. However, as I’m sure all readers of my blog know, there were sweeping changes in the last 10,000 years in the human genome due to the advent of agriculture, and, obviously, new alleles have appeared in our genome, however “it is not clear whether these new alleles have led to the emergence of new evolved psychological mechanisms in the last 10,000 years.”
General intelligence poses a problem for evo psych since evolutionary psychologists contend that “the human brain consists of domain-specific evolved psychological mechanisms” which evolved specifically to solve adaptive problems such as survival and fitness. Thusly, Kanazawa proposes in contrast to other evolutionary psychologists that general intelligence evolved as a domain-specific adaptation to deal with evolutionary novel problems. So, Kanazawa says, our ancestors didn’t really need to think inorder to solve recurring problems. However, he talks about three major evolutionarily novel situations that needed reasoning and higher intelligence to solve:
1. Lightning has struck a tree near the camp and set it on fire. The fire is now spreading to the dry underbrush. What should I do? How can I stop the spread of the fire? How can I and my family escape it? (Since lightning never strikes the same place twice, this is guaranteed to be a nonrecurrent problem.)
2. We are in the middle of the severest drought in a hundred years. Nuts and berries at our normal places of gathering, which are usually plentiful, are not growing at all, and animals are scarce as well. We are running out of food because none of our normal sources of food are working. What else can we eat? What else is safe to eat? How else can we procure food?
3. A flash flood has caused the river to swell to several times its normal width, and I am trapped on one side of it while my entire band is on the other side. It is imperative that I rejoin them soon. How can I cross the rapid river? Should I walk across it? Or should I construct some sort of buoyant vehicle to use to get across it? If so, what kind of material should I use? Wood? Stones?
These are great examples of ‘novel’ situations that may have arisen, in which our ancestors needed to ‘think outside of the box’ in order to survive. Situations such as this may be why general intelligence evolved as a domain-specific adaptation for ‘evolutionarily novel’ situations. Clearly, when such situations arose, our ancestors who could reason better at the time these unfamiliar events happened would survive and pass on their genes while the ones who could not die and got selected out of the gene pool. So general intelligence may have evolved to solve these new and unfamiliar problems that plagued out ancestors. What this suggests is that intelligent people are better than less intelligent people at solving problems only if they are evolutionarily novel. On the other hand, situations that are evolutionarily familiar to us do not take higher levels of g to solve.
For example, more intelligent individuals are no better than less intelligent individuals in finding and keeping mates, but they may be better at using computer dating services. Three recent studies, employing widely varied methods, have all shown that the average intelligence of a population appears to be a strong function of the evolutionary novelty of its environment (Ash & Gallup, 2007; D. H. Bailey & Geary, 2009; Kanazawa, 2008).
Who is more successful, on average, over another in modern society? I don’t even need to say it, the more intelligent person. However, if there was an evolutionarily familiar problem there would be no difference in figuring out how to solve the problem, because evolution has already ‘outfitted’ a way to deal with them, without logical reasoning.
Kanazawa then talks about evolutionary adaptations such as bipedalism (we all walk, but some of us are better runners than others); vision (we can all see, but some have better vision than others); and language (we all speak, but some people are more proficient in their language and learn it earlier than others). These are all adaptations, but there is extensive individual variation between them. Furthermore, the first evolved psychological mechanism to be discovered was cheater detection, to know if you got cheated while in a ‘social contract’ with another individual. Another evolved adaptation is theory of mind. People with Asperger’s syndrome, for instance, differ in the capacity of their theory of mind. Kanazawa asks:
If so, can such individual differences in the evolved psychological mechanism of theory of mind be heritable, since we already know that autism and Asperger’s syndrome may be heritable (A. Bailey et al., 1995; Folstein & Rutter, 1988)?
A very interesting question. Of course, since it’s #2017, we have made great strides in these fields and we know these two conditions to be highly heritable. Can the same be said for theory of mind? That is a question that I will return to in the future.
Kanazawa’s hypothesis does make a lot of sense, and there is empirical evidence to back his assertions. His hypothesis proposes that evolutionarily familair situations do noot take any higher levels of general intelligence to solve, whereas novel situations do. Think about that. Society is the ultimate evolutionary novelty. Who succeeds the most, on average, in society? The more intelligent.
Go outside. Look around you. Can you tell me which things were in our ancestral environment? Trees? Grass? Not really, as they aren’t the same exact kinds as we know from the savanna. The only thing that is constant is: men, women, boys and girls.
This can, however, be said in another way. Our current environment is an evolutionary mismatch. We are evolved for our past environments, and as we all know, evolution is non-teleological—meaning there is no direction. So we are not selected for possible future environments, as there is no knowledge for what the future holds due to contingencies of ‘just history’. Anything can happen in the future, we don’t have any knowledge of any future occurences. These can be said to be mismatches, or novelties, and those who are more intelligent reason more logically due to the fact that they are more adept at surviving evolutionary novel situations. Kanazawa’s theory provides a wealth of information and evidence to back his assertion that general intelligence is domain-specific.
This is yet another piece of evidence that our brain is not special. Why continue believing that our brain is special, even when there is evidence mounting against it? Our brains evolved and were selected for just like any other organ in our body, just like it was for every single organism on earth. Race-realists like to say “How can egalitarians believe that we stopped evolving at the neck for 50,000 years?” Well to those race-realists who contend that our brains are ‘special’, I say to them: “How can our brain be ‘special’ when it’s an evolved organ just like any other in our body and was subject to the same (or similar) evolutionary selective pressures?”
In sum, the brain has problems dealing with things that were not in its ancestral environment. However, those who are more intelligent will have an easier time dealing with evolutionarily novel situations in comparison to people with lower intelligence. Look at places in Africa where development is still low. They clearly don’t need high levels of g to survive, as it’s pretty close to the ancestral environment. Conversely, Eurasian societies are much more complex and thus, evolutionarily novel. This may be one reason that explains societal differences between these populations. It is an interesting question to consider, which I will return to in the future.
In 2005, Linda Gottfredson published What If the Hereditarian Hypothesis Is True? in the journal Psychology, Public Policy, and Law defending Rushton and Jensen’s (2005) conclusions on the black-white IQ gap. This gap in intelligence between the races has been noticed since the IQ test’s inception 100 years ago. What if the hereditarian hypothesis is true—what if there are genetic differences in intelligence between races? How should society handle such a ‘discovery’ if one were to occur?
In Rushton and Jensen’s opus paper, they didn’t set out to prove that the hereditarian hypothesis is true, rather they set out to prove that the hereditarian hypothesis—which states that 50 percent of racial differences in intelligence come down to genetic factors with environment dictating the other 50 percent—is more tenable the culture-only hypothesis—0 percent genetics 100 percent environment. Gottfredson states that the hereditarian hypothesis becomes scientifically plausible “only after five evidentiary requisites have been met”: “IQ differences among same-race individuals represent (a) real, (b) functionally important, and (c) substantially genetic differences in general intelligence (the g factor), and mean IQ differences between the races likewise reflect (d) real and (e) functionally important differences on the same g factor.” (Gottfredson, 2005: 311) The past one hundred years of intelligence testing has proven all of this. The black-white differences in intelligence are on subtests that are more heritable, proving a genetic component.
The hereditarian hypothesis has been proven by adoption studies such as the Minnesota Transracial Adoption Study, to differences overall in IQ tests, to differences in life success etc. Environmentalists believe it’s ‘racism’ or ‘classism’ that’s the cause for racial/ethnic/class differences in achievement, when a genetic explanation makes a lot more sense.
The Denial of the Hereditarian Hypothesis
The denial of the hereditarian hypothesis has greatly harmed American society. Before the push for multiculturalism in the 60s, a genetic reason for racial/class differences was widely accepted. Minorities couldn’t perform well in school in comparison to whites because they had lower innate g. The difference in g causes differences in wealth attainment, salary, mortality, fitness, educational attainment, and other pertinent achievements. This then leads to programs with an abysmal ‘success rate’, such as Head Start. Head Start does not work, its gains fade away in a few years after the program. It’s time to stop Head Start, because it makes people believe that parental intervention can have any kind of effect on a young child, when it’s shown that these so-called gains fade away in a few years as the heritability of intelligence increases. Individuals differ on g, races differ on g, there are differences in achievement and more people in one SES bracket and other people in another SES bracket and it’s down to g. Denying the hereditarian hypothesis wastes taxpayer money as more and more money goes towards programs like Head Start that don’t do anything to close any of the gaps they promise to close.
Academic achievement in math, science, art, humanities, and second language were all shared by the same genes. They found that 60 percent of the results in GCSE scores were attributed to genetic factors. Genes and not upbringing had more of an effect on the scores one receives on the GCSE.
Moreover, other behavioral traits such as psychopathology and personality also account for genetic influence on GCSE scores beyond that predicted by intelligence. This shows that ‘nature’ wins out in the nature-nurture debate. If individual differences in test scores are largely determined by genetics, why not the black-white difference?
Individuals nor groups are ever ‘equal’ in terms of any capacity. One will be better at something than someone else, and that will largely be determined by genetic factors. Training and repetition brings out the best in one that’s genetically inclined to excel. We accept genetic differences for differences in sports, such as sprinting and distance running. They are genetically inclined to excel at those competitions due to fast and slow twitch muscle fibers. Take Usain Bolt. Do you think anyone can train to get to that level? Do you think random Joe can just wake up one day and decide to try to be the fastest man in the world? If you say no, you’re a hereditarian. Of course Bolt’s training makes him better, but without his genetics, he wouldn’t be the fastest man in the world.
Now take the genetic differences from sports (that any sane person would recognize), and think about that in regards to brain power. We are talking about 2 groups that have been genetically isolated for tens of thousands of years. They had to do different things to survive and both faced different selective pressures that would have an effect on intelligence.
The worldwide differences in IQ between East Asians, Europeans and Africans; an inverse correlation between the race differences and brain attributes and black-white-East Asian differences in body maturation; . 2 and .4 correlations with skull size and in vivo brain volume, moderately high correlation of .6 to .7 of different IQ test’s g loadings on the magnitude of the black-white-East Asian differences as well as the measures of the subtests being rooted in biological and genetic processes; rising heritability of IQ; differences in crime, gestation, and sex ratio at birth, law-abidingness, marital stability; and a genetic divergence of world population groups during evolution. The most telling one is the last one, genetic divergence of world population groups during evolution. These differences in the brain are rooted in genetic factors. The hereditarian hypothesis fully explains within and between group differences in achievement and intelligence. No “culture-only” hypothesis could ever convince me otherwise.
Richard Nisbett has attempted to say that the hereditarian hypothesis is wrong and that culture-only theory is the only game in town. He couldn’t be more wrong. Citing studies like Moore and Eyferth to make your case against the hereditarian hypothesis won’t get you anywhere. They had a smaller sample size, and some of the subjects were extremely young. Environmentalists use these studies to say that the difference in IQ comes down to a type of ‘ghetto’ environment that saps American blacks’ intellect and that raised away from that type of environment, they’d be able to score on par with whites. Except that’s not what was found in the Minnesota Transracial Adoption Study. This is the only study to test the children again at age 17, when genetics would be taking its full effect. The racial gap in intelligence still stayed the same (Rushton and Jensen, 2005: 258). I’ve written about the strong evidence for the hereditarian hypothesis in regards to adoption studies and how they support the hypothesis that genetics, and not culture, are the cause for differences in intelligence.
If the Hereditarian Hypothesis is Accepted What Policies Should Change?
If the general public were to ever accept a genetic hypothesis for individual and group differences as a whole, then affirmative action and other such programs that shoehorn kids with lower ability into schools should be abolished and these spots should be filled on merit. Sure there would be fewer blacks and more whites, Jews, Asians, than blacks, ‘Hispanics’ and others but that’s how a merit-based society looks, not one based on feelings and imaginary causes of racism as the culprit for any types of intellectual downfalls. When we come to our senses with genetics and educational achievement and intelligence—which should be coming soon due to the advent of CRISPR—then America can start to become less polarized, in my opinion, on the so-called ‘racist system’ ‘holding down’ minorities. Maybe if people/groups accepted they were less intelligent and it was due majorly to genetic factors, then some of this racial animosity between groups in America will die down. That’s an extremely far reach, though, and I can see them then arguing that accepting by accepting the hereditarian hypothesis then we should continue these programs.
That’s an extremely far reach, though, and I can see them then arguing that accepting by accepting the hereditarian hypothesis then we should continue these programs due to genetic differences. They would say “Well, as a group, we are less inclined to make it into higher areas of learning so we, therefore, should continue to receive these benefits.” To that I would say you’ve been taking advantage of these benefits for 50 years and what’s changed? Billions of dollars have been spent on affirmative action and related cases since the 60s and what has changed? These groups still complain and talk about being oppressed by ‘the man’ not getting what they want. Yet there is an ongoing racial preference for blacks and ‘Hispanics’ over whites and Asians in US medical schools. This is all an effect of affirmative action and the policies it brings to American institutions. Admission into places of higher learning should be completely merit-based, not based on what racial/ethnic group you belong to. That in and of itself is continuing the so-called ‘racism’ and ‘prejudiced attitudes’ that people complain about since they insist on having special privileges based on their ancestral background.
If we were to accept the hereditarian hypothesis as a country, I’d hope to see an abolishment of affirmative action, Head Start, and related programs that do not work. The acceptance of the hereditarian hypothesis would only be a net gain over time, as people would learn to not blame ‘the man’ on their problems, but would look to better themselves in ways that accentuate their strengths. Since any attempt at raising scholastic achievement has failed due to the heritability of intelligence and how it increases as one ages (which is why Head Start doesn’t work and should be abolished) once this is accepted then other avenues can be taken to address these issues that don’t focus on attempting to raise scores. Gottfredson states at the end of her paper that we should have targeted intellectual support for those with an IQ below 80. She also says we should make some jobs less complex, ie “inadequate or overly complex labeling, instructions, and forms”, target training and education towards people with that level of intelligence, and provide more assistance in daily living matters, This can increase their QoL and ability to attain meaningful employment.
She sees a more positive outlook in the future than I do. I see things become more stratified as automation rolls out. This will have the lower IQ people out of work, while the higher IQ people still are sitting well at the top due to the increasingly complex society that we make for ourselves. Accepting the hereditarian hypothesis can ease this slightly by targeting programs at the less intellectually inclined as well as attempt to soften the claims of ‘racism’ when this starts to really become noticeable. The only way to explain such a disparity is with a genetic hypothesis, at least 50/50 genetics culture. The culture-only theory has no leg to stand on. Once we accept that individual and group differences are due to genetics, then we can begin to accept some of the differences in our society in terms of class and race.
Over a ten year period in France, from 1999 to 2008-9, IQ has declined in France by almost 4 points. What is the cause? Immigration? Dysgenics? A reversal of the Flynn Effect? No doubt that numerous people would attribute the decline in intelligence in France due to MENA and SSA immigration. But is this true?
Lynn and Dutton (2015) show how differing studies show both positive and negative gains in IQ. To prevent further evidence of these negative Flynn gains, they looked to the IQ of France from 1999-2009.
The WAIS-III was standardized in France in 1999 while the WAIS-IV was standardized in 2009. This was a great opportunity to see if the intelligence of the French dropped using the new WAIS-IV. The sample was of 79 people who were of a different sample than that of the broader WAIS-IV French standardization. The average age of the sample was 45, ranging between 30 and 63 years of age. Half of this sample took the WAIS-IV first while the other half took the WAIS-III first to control for practice effects. They used a separate sample to compare the norms of generated by the two standardizes samples.
The above table from the paper, table 3, shows the comparison between the two WAIS tests. Positive ds indicate lower scaled scores on the III in comparison to the IV and thusly higher scores. What these data show is that the IV is harder than the III and IQ declined because the test got ‘tougher’ (because full-scale intelligence declined). As noted above, this phenomenon of decreasing IQ scores has been noticed for about 20 years now. The symbol search showed the smallest decline while there was no change in digit span. The biggest gain was in vocabulary.
This is pretty shocking. In ten years, verbal comp decreased by 4 points, perceptual reasoning index by 3.1 points, no change in working memory index, processing speed index decreased by .7 points, perceptual organization index decreased by 3.9 and the whole full-scale IQ decreased by 3.8 points. Lynn and Dutton discuss the results:
In addition, the Full Scale IQ on the WAIS IV sample of 79 subjects was calculated based on a comparison with the WAIS IV sample of 876 subjects, which was representative of the French population on key variables such as education and region. The scores of this sample of 876 subjects were set at 100 and a comparison made with the sample of 79 subjects. As can be seen in Table 4, on this basis the IQ of the sample of 79 subjects was 101.1 with an SD of 14.7, where the French norm would be 100 and the SD 15. As such, the smaller sample can be regarded as representative of the French population in terms of intelligence.
So this small sample can be regarded as representative of the French population. Lynn and Dutton say that the digit span showing no increase corroborates findings from another researcher that showed that there was no change in forward or backward digit span in 85 years. They then say:
. . .improvements in the quality of nutrition during the twentieth century made a major contribution to increasing IQs. But it seems improbable that the quality of nutrition declined in recent years in France and in the other economically developed countries in which declining IQs have been reported.
So one possible cause is that nutrition has declined in France. From Dubuisson et al, 2010:
These repeated surveys highlighted the fact that trends in French food habits have moved towards an average European diet at the crossroads between Mediterranean and Northern diets, and that food consumption changes impacted, to a lesser extent, nutritional intake.
It shows that the French diet is in between Med and Nord diets. Really, as Lynn and Dutton asserted, there was no decline in nutritional quality for the French.
Another possible cause is a decrease in quality of schools. Flynn says a part of the reason for the rise in IQ was due to the advent of scientific thinking. However, this is not a good explanation either since school quality seems to not have been affected.
Flynn also talks about the media and its role. Lynn and Dutton say:
However, this would not explain declines in other forms of intelligence and, moreover, it might be argued that the desire and ability to read such literature would be underpinned by general intelligence and so a decline in the consumption of such literature would partly reflect a decline in general intelligence, as vocabulary is a measure of intelligence.
It is also worth noting that, apparently, reading may actually increase general intelligence (post coming on that soon).
Now, finally, the theory we’ve all been waiting for: Is it increased immigration?
Lynn and Dutton state:
This increase has occurred throughout western Europe and a number of studies have shown that immigrants from North Africa and south-west Asia typically have an average IQ of around 85 to 90 (Lynn, 2006, Lynn, 2008, Lynn and Vanhanen, 2012 and Rindermann and Thompson, 2014; for a large meta-analysis see te Nijenhuis, de Jong, Evers, & van der Flier, 2004). This conclusion has been confirmed by Kirkegaard (2013) who has shown that in Denmark the number of non-European immigrants increased from approximately 50,000 in 1980 to 400,000 in 2012 and the IQ of non-European immigrants in 18–19 year old military conscripts was 86.3, relative to 100 for indigenous Danes. These immigrants are likely to have had some impact on reducing the average IQ of the populations, but it is doubtful whether the increase in the number of immigrants with lower IQs has been sufficiently great to have had a major effect.
I personally don’t think that migration into Europe from MENA and SSA countries has been enough to put that big of a dent (over 1/3rd of an SD) in average IQ in France, and Europe as a whole. Since people are coming from areas closer to the equator and have higher rates of children since they are r-selected, could this be why France has seen a decrease in intelligence?
Woodley of Menie and Dunkel (2015) reviewed Lynn and Dutton’s paper and said:
Replacement migration in France involving populations exhibiting lower means of IQ and higher rates of total fertility, such as Algerians, Moroccans, Tunisians and Roma (Čvorić, 2014 and Lynn and Vanhanen, 2012) may be increasing the rate of secular losses at the level of g, consistent with speculations advanced in Dutton and Lynn (2015), however the additional loss in g due to this process is anticipated to be very small. Based on a simulation, Nyborg (2012) estimates that in Denmark, replacement migration may be reducing heritable g by .28 points per decade, which would increase the overall loss in g to 1.51 points per decade ( Woodley of Menie, 2015), this still being only 37.75% of the loss observed in the French cohort.
An Environmental Explanation?
Since we still need an explanation for 62.25 percent of the 3.8 decrease in full-scale IQ other than dysgenic fertility, are there any environmental explanations? Environmental explanations can be anything from child abuse, to poor schooling, to poor nutrition, etc. Was there an increase in any of these or other variables that negatively affect IQ which would explain the 3.8 point decline in IQ?
One of the most likely candidates is nutrition. Lack of certain vitamins, especially in childhood, would prevent the brain from receiving the proper nourishment to grow.
The INCA study took record of food consumption from 2,373 people aged 4 to 92 from a 7-week period and from that they saw which nutrients they were deficient in (Touvier et al 2006). To measure if and how much they were nutrient deficient, they used the Estimated Average Requirement (EAR). The vitamins used were calcium, magnesium, iron, vitamins C, A, B6, and B12, thiamin, riboflavin, niacin, pantothenic acid, and folate. A lot of these have to do with proper brain functioning and ability to reach its full-size potential. For instance like the B vitamins and iron. Being deficient in those nutrients depresses brain size and with it IQ. For instance, being deficient in vitamin B 12 and folate leads to decreased brain size in childhood. The negative effects of being deficient in these nutrients may partially explain some of the 3.8 point decrease in full-scale IQ.
Regarding the prevalence of the aforementioned nutrient deficiencies in these populations, the authors state:
We also calculated daily consumption of 44 food groups by age and gender. This paper shows how the combination of both data sets, i.e., inadequacy and food consumption data, allows a preliminary screening of potential food vehicles in order to optimize fortification. The prevalence of inadequacy was particularly high for the following groups: for calcium, females aged 10-19 years (73.5%) or aged 55-90 years (67.8%), and males aged 15-19 years (62.4%) or aged 65-92 years (65.4%); for magnesium, males aged 15-92 years (71.7%) and females aged 10-90 years (82.5%); for iron, females aged 15-54 years (71.1%); and for vitamin C, females aged 15-54 years (66.2%). Two examples are provided to illustrate the proposed method for the optimization of fortification.
Most vitamins and minerals have positive effects on brain functioning, some more than others, but notice the prevalence of iron defieciency in the females aged 15-54 years (71.1 percent). With the cohort cited by Lynn and Dutton (2015) and Woodley of Menie and Dunkel (2015) being aged 30 to 63 with an average age of 45, the prevalence of iron deficiencies in the INCA study, along with the other deficiencies in the cohort, may partially be responsible for the decline in IQ.
The Flynn Effect
One of the biggest mysteries in psychology is the Flynn Effect; the fact that over the 20th century, people have been performing better and better on IQ tests. Of course, the average IQ in Western countries by definition is always about 100, however because people keep scoring higher every decade, the tests routinely have to be made more difficult and the norms must be regularly updated to keep the mean IQ from rising far above 100.
However, in first-world countries, in the past 20 or so years, it has been in decline, particularly in France. It’s due to a mix of dysgenic fertility and nutrient deficiencies. Since Flynn gains are largely due to advancements in better nutrition, Flynn loses would then be attributed in part to nutrient deficiencies as well as dysgenic fertility.
The cause for the 3.8 decrease in IQ in France is low fertility rates amongst the French population as well as nutrient deficiencies. Clearly, ameliorating this decrease in IQ can be reversed by the K-selected having more children and healthier eating habits. Drops in IQ won’t be attributed to MENA and SSA populations until the future, but for now, the cause for the decrease is the French themselves.
The relationship between intelligence and obesity is often misinterpreted. Numerous studies have concluded that becoming obese leads to a drop in IQ. This mistake happens due to improper interpretation of cross-sectional studies. However, analyses of population-based, longitudinal data show that low intelligence from birth causes obesity. No credible evidence exists for obesity lowering intelligence. There are, however, mountains of evidence showing that low intelligence from childhood leads to obesity (Kanazawa, 2014).
Kanazawa (2014), reviewed the data on the research between obesity and IQ. What he found was that those studies that concluded that obesity causes lowered intelligence only observed cross-sectional studies. Longitudinal studies that looked into the link between obesity and intelligence found that those who had low IQs since childhood then became obese later in life and that obesity does not lead to low IQ. Those with IQs below 74 gained 5.19 BMI points, whereas those with IQs over above 126 gained 3.73 BMI points in 22 years, which is a statistically significant difference. Also noted, was that those at age 7 who had IQs above 125 had a 13.5 percent chance of being obese at age 51, whereas those with IQs below 74 at age 7 had a 31.9 percent chance of being obese. This data makes it clear: low IQ is correlated with obesity, so we, therefore, need to find sufficient measures to help those with lower IQs to learn how to manage their weight. Moreover, the lack of ability to delay gratification is also correlated with low IQ (Mischel, Ebbeson, and Zeiss, 1972).
Less intelligent individuals are more likely to become obese than those who are more intelligent. With what we know about low IQ people and how there is a strong relationship between low intelligence and lack of ability to delay gratification, we can see how this lack of thought for future problems for their actions in the present can manifest itself in obesity.
This study claims that there is a link between morbid obesity and a drop in IQ. The researchers compared 24 children who weighed 150 percent of their bodyweight before age 4 with 19 children and adults with Prader Willi’s Syndrome, using 24 siblings as controls as “they share the same socioeconomic environment and genetics”. Prader Willi’s Syndrome (PWS) is a chromosomal disorder in which chromosome 15 is deleted. They have an almost insatiable desire to eat,which can cause one suffering from PWS to eat themselves to death. Those with PWS were found to have an IQ of 63, while those who became obese were found to have an IQ of 78 with the control siblings having an IQ of 106. The researchers were surprised to see such a difference in IQ between siblings. They then state that this could be one facet of obesity that could be irreversible. MRI scans of the cohort discovered white matter lesions on the subjects with PWS and early-onset obesity. The researcher says that these lesions could affect food seeking centers in the brain leading to a want to gorge on food. Seeing how those with PWS eat when unsupervised, this is an interesting hypothesis.
This study compared 49 teens with metabolic syndrome and 62 peers without the disorder, while controlling for socioeconomics status. They found significantly lower scores in arithmetic, attention and attention span, spelling, mental flexibility and regions of the brain with lower volumes of matter in the hippocampus and white matter integrity.
There are a few problems with these two studies. In a population-representative birth cohort study of 1037 children, it was found that cohort members who became obese had a low IQ, as expected. But, contrary to what your study said, cohort members didn’t exhibit a decline in IQ from becoming obese, they instead had a lower IQ since childhood. There is no evidence of obesity contributing to a decline in IQ, even in obese individuals and those on the verge of metabolic syndrome. Another problem is that they wrongly conclude that obesity leads to lowered intelligence, completely misinterpreting the extremely strong negative correlation between obesity and intelligence.
This study shows how obese mothers give birth to less intelligent children. In an observational study (already garbage), the researchers took 3412 participants and found a strong relationship with pre-pregnancy obesity and math and reading scores in children. For math, a 3 percent reduction was observed. There was a 3-point drop in reading scores with math scores showing a decline of 2 points. These differences are within the normal variation between tests, so it’s nothing to take note of. Also, this is an observational study. I have shown above that longitudinal studies are superior for this, as well as researchers misinterpreting the results found from their studies.
There is a strong relationship between parental years of education and childhood obesity. Since the mother’s IQ is the most important predictor of a child’s IQ *, that passes on to the child as well. (BMI is also 80 percent heritable). **.
So because of those factors involving the mother and child, that is what accounts for it. Not the environmental factors brought up.
This study claims that overweight parents are more likely to fail. This is all due to the fact that low IQ people are more likely to be obese or overweight, with heritability of BMI being .8, you can see how low IQ is the cause of both of those variables.
This shows that binge eating is linked to memory loss. I heard about a study a few months ago actually like this. Rats were fed high fat diets and they noticed that the brain microglia actually started to eat neuronal pathways actually leading to a decrease in cognitive ability. But they said that returning to a new diet will stop its effects. Researchers say the negative cognitive effects are reversible, but I already gave the citstion about obesity not being linked to decreased IQ. I should also note that this study was carried out on rats and while this may be a factor for humans as well, a few studies need to be done.
Binge eating, however, actually has a genetic component. Though this was only observed in girls. One reason I can think of for this is that women need higher body fat for a leptin release so puberty can begin so they can bear children.
This article purports to show 5 ways obesity affects the brain. Obesity does cause food addiction, however, those who lack the ability to delay gratification are more likely to not be able to control their impulse to overeat. I always link to the MRI scan showing the control, obese and cocaine user’s brain. Interesting to see that sugar is just as addictive as cocaine. Obesity doesn’t make us more impulsive. Check out the Marshmallow Experiment, as well as its follow-up studies. Those who are more impulsive are more likely to be obese, as well as have lower SAT scores.
Satoshi Kanazawa also noted that childhood IQ predicted whether or not one would become obese at the age of 51. General intelligence in childhood has a direct effect on weight gain, BMI, and obesity, net of parents education and SES, parents BMI, the child’s social class, and sex. More intelligent children grew up to make healthier choices, and therefore stayed leaner than those children who were less bright. The link between childhood obesity and intelligence also shows that the effect between childhood g is unmediated by education of income. Meaning, those with lower IQs in a higher socioeconomic bracket STILL have the same chance of becoming obese as those in the lower socioeconomic bracket. Finally, parental BMI itself is a consequence of parental general intelligence, which the parents pass on to their children. This shows the extremely high heritability of obesity as well as showing how intelligence plays a factor in the causes of obesity.
The known differences in ethnic obesity rates generally mirror the intelligence of those populations. All populations are showing a sharp dysgenic decline, which coincides with a more obese population as well. Sociologists and the like may say that those who are poor cannot afford the same types of food that those who have more wealth can. However, this is a false statement. Whole foods are not more expensive. The conclusion that was (obviously) reached is that there is expensive and non-expensive junk food as well as whole foods. Natural diets will not cost more, all things being equal. If you know how to eat and how to buy food, you will avoid spending too much money. This goes back to intelligence. One with a higher IQ will be able to think of what his present actions will lead to in the future while those with a lower IQ live in the now without a care for the future, which then manifests itself in their obesity.
There are numerous articles showing that the causality for low intelligence is not becoming obese, but that those who become obese have a lower IQ since childhood. Longitudinal studies show the relationship, while observational studies show that obesity drops intelligence. Clearly, observational studies are inferior for seeing the relationship between IQ and obesity. This then leads to researchers misinterpreting the data and drawing wrong conclusions.
** This is a great one. In a meta-analysis of twin and family studies, including mono and dizygotic twin studies, with a sample of 140,525 people, heritability of BMI was found to be between .75 and .82. Both extremely high correlations. Since the heritability of intelligence as well as height (another good predictor of intelligence), there is good evidence for the claim that becoming obese is due to lower childhood IQ, which is genetic in nature.
The Chinese have one of the highest IQs in the world. Their 100 and 108 in Hong Kong give them an average of 104. Chinese intelligence has been increasing from the 1940s all the way to today. This is the ‘Flynn Effect’ in action. Lui and Lynn (2013) reported that IQ scores are improving for 12-year-old Chinese children. The increases are as follows: 6.19 points for full-scale IQ, 6.55 points for performance IQ, and 1.91 points for verbal IQ. The Jintan Child Study is an ongoing longitudinal study to show the effects of health and cognitive ability.
They used 1656 6th graders (55.5 percent boys and 45.5 percent girls, “consisting of 24.3% of all children in this age range in the Jintan city region born in 1999.”) who either graduated or currently were in the grade with an average age of 12.2 years. The study from 86-87 used only individuals from urban areas, so Liu and Lynn did the same. They conclude that over the 26 years from the original study, between the two data sets that increases of 2.38 points on full-scale IQ, .73 points on verbal, and 2.52 points on performance IQ per decade. They theorize that economic development is a cause of rising IQ scores due to better nutrition. The study concludes a 105.89 IQ for the 12-year-olds in the study.
Liu and Lynn (2015) also observed the same sex differences in the same magnitude in Chinese and American boys and girls. In a study of 788 children aged 12 years old, boys obtained a higher IQ by 3.75 points on average. This exactly mirrors what Rushton and Jackson (2005) say about American men and women who are college aged. They state that males score 3.63 points higher than women. Liu and Lynn state that boys obtained 4.20 points higher in performance IQ, and 2.40 points higher in verbal IQ. This is what we would expect, evolutionarily speaking. The men need to be more intelligent to provide food, whereas women need to have a higher verbal IQ to be able to talk to and take care of children. The fact that the magnitude of sex differences in IQ between men and women has been noticed in the U.S. and China shows that sex differences in the brain do exist.
Better nutrition is a definite cause for the rise in IQ for the Chinese. Richard Lynn says that better nutrition is critical for increased cognitive functioning. This is one reason why Africa’s IQ is so low. Due to more Chinese getting better jobs and making more money, they were getting higher quality foods in order to be adequately nourished. Better nutrition explains most, if not all of the Flynn Effect. It’s what to expect if this phenomenon was not on g (it’s not), it’s on the intelligence that is affected by the environment, hence, bigger increases on that type of intelligence in comparison to the intelligence highly correlated with g.
The Chinese have the largest cranial capacity at 1492 ml. The bigger one’s brain, the more cortical neurons it has which allows for better cognitive processing. Piantadosi and Kidd (2016) corroborated one of Rushton’s theories on brain size and child rearing. Mainly that r/K selection theory explains Piantadosi and Kidd’s theory of earlier births being correlated with higher intelligence due to greater necessity to care for the more vulnerable child in comparison to those with smaller brains. Moreover, since East Asians have more myelin in the brain, this too adds to their higher cognition. Since the correlation between brain size and IQ is .35, a good amount of the variance in IQ can be explained by brain size.
We can also look at Chinese outside of China. Singapore, for instance, has an IQ of 108, the highest in the world. They’re also 74.4 percent Chinese. This is then mirrored in their IQ as well as their economy. Anywhere the Chinese go they are high achievers in both IQ as well as wealth attainment.
There are other measures to show that Chinese have higher IQs. In tests of reaction times, Rushton and Jensen (2005) say that East Asians beat whites while whites beat blacks. Since faster reaction times are associated with a more efficient brain, East Asians have a higher IQ as a result of that. Though, they are weak on verbal IQ, average 99 for Chinese in America and China, they are superior in visio-spatial IQ. This is due to their ancestors evolving in the harsh winters of Siberia which lead to being more K-selected and selecting for bigger brains which lead to children being born earlier and higher intelligence evolving to better care for defenseless children. Bigger brains also evolved due to colder temperatures, which is another cause for earlier childbirth and an even bigger increase in general intelligence to adapt.
IQ in China is higher in urban areas than in rural areas, which is seen in America as well. This is due to those with higher intelligence having the ability to be able to live in the city due to a better ability to attain wealth due to higher IQ. Those in rural areas have lower IQ, some having a lower IQ genetically, while others are depressed by bad nutrition. So with better nutrition, a lot of the rural Chinese would get an IQ boost. Nutrition is critical for brain development in vitro as well as in early childhood leading into young adulthood. This ensures the brain has adequate nutrients for growth and in turn grows to its full potential.
The Chinese are the best example of Rushton’s theory of intelligence and brain size. No matter where they go, if they have adequate nutrition, they have the biggest brains and highest IQs which shows in scholastic achievement as well as wealth attainment. The increase in full-scale IQ for China in the past 30 years is due to better nutrition as well as economic growth. Singapore has one of the world’s best economies and is 74.4 percent Chinese.
This extreme K-selection, though, is causing the Chinese birth rate to drop. This is the curse for high IQ peoples. They have a lower birth rate in comparison to those with lower IQs who have a higher birth rate. The current birth rate in China is 1.66. That is devastatingly low, almost as low as Germany and Japan (both at 1.3) and they have similar IQs as well. It seems that this intelligence increase is coming with a lower birth rate. Higher intelligence is correlated with a lower sex drive so this is another cause for the lower birth rate in East Asian countries as these slight IQ increases continue to occur. The same sex differences as seen in America were also seen in China, giving more evidence to the sexual selection theory of intelligence.
In the past 100 years since the inception of the IQ test there have been racial differences in test scores. What causes these score differences? Genetics? Environment? Both? Recently it has come out that populations do differ in allele frequencies that affect intelligence. David Piffer’s “forbidden paper on population genetics and IQ” was rejected by the new editor of the journal Intelligence. In the paper, he shows how IQ alleles vary in frequency by population. One reviewer even said it should not be put up for review, which Piffer believes there was a hidden agenda or a closed minded attitude. He even puts reviewers comments and responds to them. He says science should be transparent, which is why he’s showing the researchers’ comments on his paper.
His December, 2015 paper titled: A review of intelligence GWAS hits: Their relationship to country IQ and the issue of spatial autocorrelation shows that there are differing allele frequencies in which IQ between populations that affect IQ which are then correlated highly with average IQ by country (r=.92, factor analysis showed a correlation of .86). There was also a “positive and significant correlation between the 9 SNPs metagene and IQ”(pg. 45). However, Piffer does conclude that since the 9 alleles are present within all populations (Africans, Latin Americans, Europeans, South Asians, and East Asians) that the intelligence polymorphisms don’t appear to be race-specific, but were already present in Homo Sapiens before the migration out of Africa. He then goes on to say that it’s extremely likely that the vast majority of alleles were subject do differential selection pressure which lead increases in cognitive abilities at different rates rates in different geographical areas (pg. 49). It’s of course known that differing populations faced differing selection pressures which then lead to genotypic changes which then affected the phenotype. It’s not surprising that genes that correlate strongly with intelligence have differing frequencies in different geographical populations; it’s to be expected with what we know about evolution and natural selection. Below is the scatter plot showing the relationship between polygenic score GWAS (Genome Wide Association Studies) hits and IQ:
The fact that these differences exist should not come as a shock to those who want to seek the truth, but as seen with how David Piffer didn’t even get consideration for a revision, this shows the bias in science to studies such as this that show racial differences in intelligence exist.
Piffer’s data also corroborates Lynn and Meisenberg’s (2010) finding of a correlation of .907 with measured and estimated IQ. This shows that the differing allele frequencies affect IQ, which then affect a countries GDP, GNP, and over all quality of life.
With a sample with a huge n (over 100,000 subjects) cognitive abilities tests were performed on verbal-numerical reasoning, memory and reaction time (a huge correlate for IQ itself, see Rushton and Jensen, 2005). Davies et al (2016) discovered that there were significant genome-wide SNP based associations in 20 genomic regions, with significant gene-based regions on 46 loci!! Once we find definitive proof that intelligence differences vary between individuals, as well as the loci and genomic regions responsible, we can then move on to difference in allele frequency in depth (which Piffer 2015 was one of the starts to this project).
Moreover, genes that influence intelligence determine how well axons are encased in myelin, which is the fatty insulation that coats our axons, allowing for fast signaling to the brain. Thicker myelin also means faster nerve impulses. The researchers used HARDI to measure water diffusion in the brain. If the water diffuses rapidly in one direction, that shows the brain has very fast connections. Whereas a more broad diffusion would indicate slower signaling, thus lower intelligence. It basically gives us a picture of an individuals mental speed. Thinking of reaction time tests where Asians beat whites who beat blacks, this could possibly show how differing process times between populations manifest itself in reaction time. Since myelin is correlated with fast connections, we can make the inference that Asians have more than whites who have more than blacks, on average. The researchers also say that it’s a long time from now, but we may be able to increase intelligence by manipulating the genes responsible for myelin. This leads me to believe that there must be racial differences in myelin as well, following Rushton’s Rule of Three.
Since the mother’s IQ is the best predictor of the child’s IQ, this should really end the debate on its own. Sure on average, intelligent black mothers would birth intelligent children, but due to regression to the mean, the children would be less intelligent than the mother. JP Rushton also says that regression works in the opposite way. Both blacks and whites who fall below their racial means will have children who regress to the means of 85 and 100 respectively, showing the reality of the genetic mean in IQ between the races.
Why would differing allele frequencies lead to the same cognitive processes in the brain in genetically isolated populations? I’ve shown that brain circuits vary by IQ genes, and populations do differ in this aspect, like all other differing genotypic/phenotypic traits.
East Asians have bigger brains, as shown by MRI studies. Rushton and Rushton (2001) showed that the three races differ in IQ, brain size, and 37 different musculoskeletal traits. We know that West Africans and West African-descended people have genes for fast twitch muscle fibers (Type II) (Nielson and Christenson, 2001). Europeans and East Asians have slow twitch muscle fibers (Type I) for strength and endurance. (East Africans have this as well, which allows for ability to run for distance, which fast twitch fibers do not allow for. The same is true for slow twitch fibers and sprinting events.) Bengt Saltin showed that European distance runners have up to 90 percent slow twitch fibers (see Entine, 2000)! So are genetic IQ differentials really that hard to believe? With all of these differing variables in regards to intelligence that all point to a strong genetic cause for individual differences in other genes that lead to stark phenotypic differences between the races, is it really not plausible that populations differ in intelligence, which is largely inherited?
Is it really plausible that differing populations would be the same cognitvely? That they would have the same capacity for intelligence? Even when evolution occurred in differing climates? The races/ethnicities differ on so many different variables with differing genes being responsible for it. Would IQ genes really be out of the question? Evolution didn’t stop from the neck up. Different populations faced different selection pressures, so different human traits then evolved for better adaption in that environment. Different traits clearly developed in genetically isolated populations that had no gene flow with each other for tens of thousands of years. These differing evolutionary environments for the races put different pressures on them, selecting some for high IQ alleles and others for low IQ alleles.
We are coming to a time where intelligence differences between populations will become an irrefutable fact. With better technology to see how differing genes or sets of genes affect our mind as well as physiology, we will see that most all human differences will come down to differing allele frequencies along with differing gene expression. Following Rushton’s simple rule based on over 60 variables, East Asians will have the most high IQ alleles followed by Europeans and then blacks. The whole battery of different cognitive abilities tests that have been conducted over the past 100 years show us that there are differences, yet we haven’t been able to fully explain it by GWAS and other similar techniques. Charles Murray says within the next 5 to 10 years we will have definitive proof that IQ genes exist. After that, it’s only a matter of time before it comes out that racial differences in IQ are due to differing allele frequency as well as gene expression.
“Philosophers of Science” attempt to stick their heads into the race/IQ debate to give their field more credence than it should get with the hard sciences. They use bad arguments like saying that “gene-environment interactions are widespread and hard to entangle” (Block, 1995), not knowing that identical twins reared apart grow up to be so similar (Rushton and Jensen, 2005, p. 279). The only time they should stick their heads in this debate is when they’re affirming that the methodology used to test IQ as well as racial differences in IQ are sound; otherwise, they do not have the training to assess this. Most “Philosophers of Science” defend claims that disintegrate when presented with the relevant scientific evidence (Sesarardic, 2000). I will be referencing this paper for the length of this article.
Half of the paper analyzes Lewontin’s argument to Jensen in which he uses his now famous “seed argument” in which he says you can take two seeds from the same heterogeneous population and plant them in rich and poor soil and “. . . as a result, the phenotypic differences within each of the two groups of plants will be 100 percent heritable, but the difference between the two groups will be entirely due to differences in two environments (zero heritability).” The fact of the matter is, this argument is parroted by “Philosophers of Science” when Jensen never made that argument.
Jensen then systemically dismantled every environmental argument with empirical evidence that they don’t hold up.
Other researchers then made accusations of “racism” the reason for Jensen’s overlooking of this. James Flynn, a big opponent of the hereditarian hypothesis and Rushton and Jensen in general, say that Jensen is not a “racist”. There is also something called the “X-Factor”, which is when phenotypic differences between two groups can be explained by an environmental factor that has no within-group variation at all, a 0 heritability. Racism, however, is a poor excuse for the “X-Factor”. Both Flynn and Jensen rule out discrimination as being the cause for the “X-Factor” as well.
Simply put, Jensen doesn’t make inferences that the black-white IQ gap is genetically based on one or a few variables on their own, but everything put together, that’s where the remaining evidence put. “Philosophers of Science” don’t understand heritability coefficients to be saying what they do; they wouldn’t be saying that if they knew how they worked.
Sesardic brings up how Block (1995) only mentions three pieces of empirical evidence: The “Flynn Effect”, “data about caste-like minorities”, and the small amount of genetic variation between races.
- The Flynn Effect happens uniformly in all populations at a rate of 3 points per decade but has slowed considerably. This increase began starting around 1880, coinciding with the industrial revolution. Better nutrition increased brain size in all populations, which lead to an increase in IQ. The Flynn Effect is not on g, so to make any claims that the differences in IQ between blacks and whites, or global differences in IQ for that matter, can be changed with more favoring towards environmentalist positions are not consistent with the scientific literature. In 1945, the average white IQ in America was 85, the same as the average American black IQ today. Since the differences in IQ have stayed consistent despite better nutrition in all groups, this proves that the gap is genetic in origin. Just because a change in one group over time is due to an environmental change, doesn’t mean, or even make it probable, that a difference between 2 groups at the same time is due to an environmental change. Since the Flynn Effect does not occur on g, it should be a non-factor.
- Minorities are only “caste-like” because differences in IQ are heritable, leading to racial disparities in social class differences. We can see when we match blacks, whites, and “Hispanics” for IQ (100), that some differences disappear, other differences decrease dramatically, and even blacks and “Hispanics” beat out whites in a couple of variables. Through multiple IQ tests averaged over time as well as seeing that test differences between races stay mostly the same, we can then make the inference, with all of the other evidence, that racial and ethnic differences in IQ are mostly genetic in origin with the environment having very little effect. To say that “racism” or “stereotype threat” has any bearing on these racial differences in IQ is laughable because 1) stereotype threat is only replicable in the lab and 2) racism as a variable does not exist in IQ testing.
- The small amount of genetic variation between races as an argument for the non-existence of race is meaningless. There are around 3 billion base pairs in the human genome. The human races differ on around .1 percent of the genome, or around 3 million base pairs. This is more than enough genetic difference to show phenotypic differences (obviously) as well as genotypic differences (again, obviously). Richard Dawkins in the Ancestor’s Tale writes: “What is not correct is the inferene that race is therefore a meaningless concept.” Race is a perfectly valid concept, anyone who denies it has doesn’t know of all of the studies that show the existence of race and how it’s a scientifically taxonomic concept.
Sesardic then brings up how “Philosophers of Science” continuously cite The Mismeasure of Man and Steven Jay Gould in an attempt to denigrate scientists long dead. A few “glowing reviews” from two “Philosophers of Science”:
No one has done as much as Stephen J. Gould to expose race and intelligence studies for the garbage that they often are. (Brown 1998, 5)
Stephen Jay Gould has lucidly analyzed how filling the skulls with lead shot, and comparing the weights of the lead, could easily be infected with unconscious biases. (Kitcher 1997, 171)
The garbage that they often are? Steven Jay Gould is a long discredited ideologue who put his politics before actual science, ironically giving HIM the same bias he falsely accused Samuel Morton of having. James Flynn even says that Gould’s book evades all of Jensen’s best arguments (as most always happens with this debate) with his false belief that g is “reified” therefore leading to the study of race and IQ being meaningless since he has “rebutted the g factor”. I proved the existence of Spearman’s hypothesis the other day using Jensen’s writings that he empirically verified that Spearman’s hypothesis exists in 25 independent samples of blacks and whites along with the study by Dragt (2010) who used the method of correlated vectors to empirically prove the existence of Spearman’s hypothesis. In meta-analyses of Spearman’s hypothesis, he found that differences in intelligence between groups are largely based on cognitive complexity and any so-called “biases in mental testing” cannot account for these racial differences in cognitive ability.
In the definitive refutation of Steven Jay Gould’s “reanalysis” of Morton’s skulls, Lewis, et al definitively prove by remeasuring 308 of the 670 skulls that he had no implicit biases. They also found that if Morton’s biases were true, then there would be considerable overestimates of white skulls while there would be considerable underestiamates of non-white skulls. Ironincally enough, he considered his Egyptian skulls “Negroid” and overmeasured by 12 percent. He overmeasured three of those skulls, along with Seminole (by 8 percent) and native African Nergro (by 7 percent), falsifying the claim that Morton had a bias in measuring his skulls!! As I have brought up here numerous times, as Rushton has refuted him (and defended Morton’s results) as well as Jensen giving Gould a definitive rebuttal to his book. Gould should not be being cited seriously anymore. He should only be brought up as an example of extreme bias in the context of race as well as racial differences and a whole slew of other things that are politically motivated.
He finally rounds up the paper by bringing up how TJ Bouchard, showing that the Big Five Personality Traits have a high heritabilty, gets told that they are traits that carry a social judgment. However, we now know that 40-60 percent of the variation the Big Five is heritable, so this is a meaningless claim.
Sesardic ends the paper as follows:
Why is this small segment of contemporary philosophy of science in such a sorry state? On reflection, I prefer to leave this question as an exercise for the reader. My aim in this paper is to criticize a deviant philosophical trend, not to explain how it came about or why it spread.
My answer to this question is that most philosophers seem to be leftists. We can see with the vehement race denial that they want to believe so strongly that racial differences, as well as race as whole, does not exist. The fact that they attempt to say that these things are not a reality and based on faulty methodologies shows that they do not know what they are talking about. They show large misconceptions about heritability, and continuously cite Steven Jay Gould, even when Gould has been refuted numerous times as well it being shown that they don’t correctly understand heritability. They show large misconceptions of what is understood in the field of psychometrics and heritabilities and make faulty claims about the hereditarian hypothesis.
If the hereditarian hypothesis is to be refuted (it won’t), it will be from science and not philosophy or “Philosophers of Science”.
It seems like every day something new comes out that attempts to discredit the reality of g (This paper came out in 2012.). Steven Jay Gould (in)famously wrote in The Mismeasure of Man:
The argument begins with one of the fallacies—reification, or our tendency to convert abstract concepts into entities (from the Latin res, or thing). We recognize the importance of mentality in our lives and wish to characterize it, in part so that we can make the divisions and distinctions among people that our cultural and political systems dictate. We therefore give the word “intelligence” to this wondrously complex and multifaceted set of human capabilities. (emphasis mine)
“The results disprove once and for all the idea that a single measure of intelligence, such as IQ, is enough to capture all of the differences in cognitive ability that we see between people,”
“Instead, several different circuits contribute to intelligence, each with its own unique capacity. A person may well be good in one of these areas, but they are just as likely to be bad in the other two,”
Just like The Mismeasure of Man is “the definitive refutation to the argument of The Bell Curve”, right?
In the above paper, they cite Gould twice writing:
It remains unclear, however, whether population differences in intelligence test scores are driven by heritable factors or by other correlated demographic variables such as socioeconomic status, education level, and motivation (Gould, 1981; . . .
They have been shown over numerous studies that population differences in intelligence are driven by heritable factors (Rushton and Jensen, 2005; Lynn and Vanhanen, 2006; Winick, Meyer, and Harris, 1975; Frydman and Lynn, 1988; Rushton, 2005)
More relevantly, it is questionable whether they relate to a unitary intelligence factor, as opposed to a bias in testing paradigms toward particular components of a more complex intelligence construct (Gould, 1981;
I will prove the existence of g in this article. There is also an empirical basis for the g factor.
It’s getting old now that researchers still think that they can “disprove g”, as a multitude of studies have already corroborated Spearman’s hypothesis as an empirical fact. That is, applying the scientific method, using the same hypothesis over a multitude of different studies and testing those predictions by experiment or further observation and modify the hypothesis when new information comes to light. Then, repeat the aforementioned steps until there are no discrepancies between the theory and experiment/observations.Then when consistency is obtained it then becomes a theory that provides a coherent set of premises that explain a class of events.
How many times has the Hampshire et al hypothesis been corroborated? I doubt it has been corroborated as many times as Spearman’s hypothesis has.
As I said the other day, Jensen tested Spearman’s hypothesis on 25 large independent samples, with each sample confirming Spearman’s hypothesis. Even matching blacks and whites for SES didn’t diminish the effect. Jensen then concludes that the overall chance for Spearman’s hypothesis being wrong is over 1 in a billion. Pretty high odds.
Even then, if this study were to be replicated the amount of times that Spearman’s hypothesis has, it still wouldn’t disprove g.
He (Gould) continues: “The fact that Herrnstein and Murray barely mention the factor-analytic argument forms a central indictment around The Bell Curve and is an illustration of its vacuousness.” Where, Gould asks, is the evidence that g “captures a real property in the head?
Murray states that they “barely brought up the factor-analytical argument” because it was out of date; Gould was using statistics on g that were 50 + years old. Also, a reviewer of his book for the journal Nature said that Gould’s “discussion of the theory of intelligence stops at the stage it was more than a quarter of a century ago.” Gould was using old arguments, and, as Arthur Jensen states in his response to Gould:
Of all the book’s references, a full 27 percent precede 1900. Another 44 percent fall between 1900 and 1950 (60 percent of those are before 1925); and only 29 percent are more recent than 1950.
More than half of Gould’s references in The Mismeasure of Man are outdated by more than 50 years. Clearly, he was attempting to denigrate the old studies of intelligence, i.e., phrenology, even though this recent paper in the journal Nature recently said:
The genomic regions identified include several novel loci, some of which have been associated with intracranial volume
So, we have several loci that are associated with intracranial volume; this shows that those skull studies of yesteryear weren’t crazy. Moreover, the fact that Rushton and Ankney (1996) “reviewed 32 studies correlating measures of external head size with IQ scores or with measures of educational and occupational achievement, and they found a mean r .20 for people of all ages, both sexes, and various ethnic backgrounds, including African Americans” shows that there is a correlation of .20, albeit not too high but there, with external head size and IQ. This shows that Gould’s argument on phrenology is bunk, as modern studies confirm that there is a slight correlation between head size and IQ, and therefore g.
The fact that researchers are still bringing up Gould’s arguments on g show that there really is no good argument to discount it. Basically, any and all arguments that attempt to discredit g are bunk as Spearman’s hypothesis has been empirically verified:
Conclusion: Mean group differences in scores on cognitive-loaded instruments are well documented over time and around the world. A meta-analytic test of Spearman’s hypothesis was carried out. Mean differences in intelligence between groups can be largely explained by cognitive complexity and the present study shows clearly that there is simply no support for cultural bias as an explanation of these group differences. Comparing groups, whether in the US or in Europe, produced highly similar outcomes.
Along with Jensen’s 25 large independent studies that showed that the probability that Spearman’s hypothesis is false is 1 in a billion, this proves that Spearman’s hypothesis is an empirical scientific fact.
Newman and Just, (2005) state in verbal and spatial conditions that the frontal cortex revealed greater activation for high-g in comparison to low-g, supporting the idea that g reflects functions of the frontal lobe. The “seat” of general intelligence is the prefrontal cortex (Cole, et al, 2011, Roth, 2011). This can also be verified with MRI scans that show that those who have higher g have bigger prefrontal cortexes than those with lower g.
Moreover, the fact that Colom, et al (2006) show that in their sample that neuroanatomic areas underlying the g factor could be found across the entire brain including the frontal, parietal, temporal and occipital lobes, shows that this factor is present throughout the brain and all are correlated with g and work together in concert to manifest intellectual ability.
Other researchers have also used the method of correlated vectors on functional Magnetic Resonance Imaging (fMRI), which measures brain activity by detecting changes associated with blood flow. This technique is proven useful due to the fact that cerebral blood flow and neuronal action are correlated. Lee, et al write:
In conclusion, we suggest that higher order cognitive functions, such as general intelligence, may be processed by the coordinated ability may be attributable to the functional facilitation rather than the structural peculiarity of the neural network for g. In addition, our results demonstrated that the posterior parietal regions including bilateral SPL and right IPS could be the neural correlates for superior general intelligence. These findings would be the early step toward the development of biological measures of g which leads to new perspectives for behavior interventions improving general cognitive ability.
They also used the MCV to find that the frontal and parietal lobes are associated with g. Even these studies show that g shows up throughout the brain and not in one solitary spot (though, the PFC is still the seat of intelligence), this shows yet another biological basis for g.
Hampshire, et al write:
Thus, these results provide strong evidence that human intelligence is a construct that emerges from the functioning of anatomically dissociable brain networks.
However, with the above studies confirming that the seat of intelligence is the prefrontal cortex, along with great g ability possibly be attributable to the functional facilitation rather than the structural peculiarity of the neural network for g, this shows, along with the study proving Spearman’s hypothesis, that g is a real and measurable thing. g’s seat is the prefrontal cortex, and exceptional g may possibly be attributed to the functional facilitation of the neural network for g . What all of these studies show is that all though the Hampshire paper showed how they “demonstrate that different components of intelligence have their analogs in distinct brain networks.” that a) higher order cognitive functions may be processed by the coordinated activation of widely distributed brain areas (disproving the above quote), b) the seat of g is the prefrontal cortex, c) those with more g have bigger prefrontal cortexes and therefore bigger brains since the prefrontal cortex is the ‘seat’ of intelligence and d) Spearman’s hypothesis has been corroborated numerous times by many different researchers not named Arthur Jensen.
Highfield (one of the researchers in the study) ends the article as follows:
“We already know that, from a scientific point of view, the notion of race is meaningless. Genetic differences do not map on to traditional measurements of skin colour, hair type, body proportions and skull measurements.
This is something that never ends; it always comes up no matter how many times it’s been said. People can say “race is a social construct” all they want, it doesn’t make it true as there is a biological reality to race.
Now we have shown that IQ is meaningless too,” Dr Highfield said.
When will people learn not to cite men who have smeared their legacy in an attempt to defame men who they disagreed with ideologically? Citing Steven Jay Gould in 2016 shows a bias to want to discredit g as a main factor for many things in life including SES, educational attainment, wealth attainment and so forth. The g factor is a measurable thing, with the seat of the factor being the prefrontal cortex. No amount of attempting to dispute this factor can be done, as it’s been empirically verified numerous times.