Friday, March 30, 2018

The Witch Hunt against Sam Harris

Back on April 22, 2017, Sam Harris had Charles Murray on his podcast.

You can hear it here:

Since then, Sam Harris has been hysterically attacked by all the usual suspects: blank slate Liberal journalists, Cultural Leftists, Marxists and so on. The latest attack is here.

But most of these attacks are pure lies, fraud and charlatanry. Rarely do the critics of Sam Harris have anything of substance in their criticisms when it comes to the actual science.

There are certainly a few mistakes that Sam Harris made: for example, he claimed nothing much can be done to increase the IQ of children (at 2.14 in the video above). In fact, the genetic component of children’s IQ seems to be less strong than in adulthood, and so childhood IQ is more malleable, and you can make IQ gains in childhood years. But, unfortunately, it remains true, as Charles Murray has pointed out, that the genetic component of IQ rises as a child becomes an adult, so IQ gains in childhood are generally lost as the person becomes an adult and the genetic determination of IQ rises to something like 75%.

But most of the major contentions of Charles Murray, which are actually just the findings of modern psychometrics, have never been refuted. These include the following:
(1) Culturally unbiased, fair IQ tests measure a person’s general faculty of intelligence, or what is now called Spearman’s g (general intelligence), which is clearly a unified, single cognitive trait of human beings. IQ has extraordinary predictive power in predicting school and academic achievement, socio-economic status, wealth, job productivity, and success in life.

(2) the consensus of psychometrics is that differences in individual variance of IQ between people is about 0.75 heritable. Even the liberal/leftist American Psychological Association (APA) admitted this in the 1990s and accepted the 0.75 figure (see Neisser et al. 1996: 96). Worse still for Leftists, even the democratic socialist James R. Flynn (after whom the “Flynn Effect” is named) – the leading environmentalist on gaps in IQ between population groups – himself accepts that current evidence shows that the heritability of IQ variance between adults is probably about 0.75 (Dickens and Flynn 2001: 346). Very good evidence for this comes from twin studies (especially genetic twins adopted and separated at birth) and adoption studies (Plomin and Petrill 1997; Bouchard 2009 and 1998), and increasingly genetic science. The particularly strong evidence is that siblings (either fraternal or genetic) adopted at birth or infancy will have IQs strongly correlated with their biological parents, while a correlation with their adopted parents is either very low or almost zero (Petrill and Deater-Deckard 2004; Hunt 2011: 230–231; Haier 2017: 47).

(3) Moreover, the heritability of IQ rises with age, so that by the time one is an adult perhaps as much as 80% of IQ is heritable (Plomin and Spinath 2004; Plomin and Deary 2015).

(4) There are real differences between the IQs of men and women. Men and women have a different distribution of IQs when plotted on a bell curve graph: the IQ scores of women tend to cluster around the average (with less distribution in upper and lower ranges), while male IQs tend to be distributed less around the average and more in the upper and lower ranges as compared with the IQ distribution of women (see Hedges and Nowell 1995; Lubs 1999; Roberts 1945; Deary et al. 2007). There may well be a small difference between the average IQ of men as compared with that of women (Lubs 1999; Johnson and Bouchard 2007; Nyborg 2005). Men appear to have a slightly higher average IQ, with about a 3–5 point advantage over women. By examining the sub-tests of IQ tests, we have discovered that – in terms of sub-tests and specific cognitive abilities – men and women also differ. Women tend, on average, to be much better at verbal abilities and language, but men tend on average to outperform women on numerical/mathematical and spatial cognitive abilities (Neisser et al. 1996; Wechsler 1958: 144–149; Lubs 1999; Johnson and Bouchard 2007; Johnson et al. 2008; Halpern et al. 2007).

(5) The average IQs of different human population groups who have been subject to divergent evolution in different regions as measured by modern psychometrics is different. You can see the data as organised by region and by nation here. The average IQ for European people is about 100. We can see the average IQ of population groups as follows:
(1) Ashkenazim | 107
(2) East Asians | 105
(3) white Europeans | 100
(4) Inuit-Eskimos | 91
(5) South East Asians | 87
(6) Native American Indians | 87
(7) South Asians & North Africans | 84
(8) Sub-Saharan Africans | 82.
Notably, the most recent metastudy of Wicherts et al. (2010) finds that the average IQ of sub-Saharan Africans is just 82.

It would appear that these differences in average IQ between populations may well have an evolutionary, genetic and environmental explanation, not just a purely environmental one.
Everywhere we look modern science is exploding the religious cult of blank slateism and social constructivism, as can be seen here, here, and here. But blank slateism remains a fanatical quasi-religious article of faith for Liberals, Leftists and even some Conservatives.

For example, take the case of violence in human societies. Contrary to Leftist mythology, the finding of modern social science is actually that violence cannot be properly explained by poverty or unemployment (see Pinker 2011: 142; Zimring 2007: 63; Levitt 2004). If you think about it and look at the data, the “poverty” explanation is absurd: for example, women are subject in all societies to extreme poverty to varying degrees, but why is it the case that women commit hardly any violent crime at all?

Instead, it is very likely that the general phenomenon of violence is explained by biology: it is a combination of certain genetically-determined cognitive traits that causes a human being to be violent and aggressive. These traits are likely to be as follows:
(1) low impulse control + high time preference;

(2) a high genetically-determined predisposition to aggression and violence, driven either by high levels of testosterone, or the Warrior gene (MAOA-L) and other undiscovered polygenetic factors, and

(3) low IQ.
Notably, it is men who commit the overwhelming majority of violence, not women, and men who are most affected by these traits, which are distributed unevenly in the male population. But the combination of these traits in certain men is deadly: most violence will be from the minority of men who have the misfortune to have inherited these traits, and so most violence in society, fundamentally, has a biological explanation.

At any rate, the hysterical attacks on Sam Harris (or Charles Murray) over IQ and average IQ differences are absurd, because Sam Harris isn’t the source of the scientific data on IQ and genetics that are discrediting the blank slateist Left: the actual source is just mainstream science itself.

But Cultural Leftists and Liberals need a figure of hate to blame their own humiliation and intellectual failure on. That figure is Sam Harris at the moment.

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  1. The Ezra Klein article you link to is not really with-hunty in nature. It links to:

    which to my (non-specialist in this area) mind presents a serious and well argued challenge to Murray's theories.

    1. Sure it is. The whole bit about how presumptuous and awful it is for “two white men” to even discuss the issue; explicitly timing a discussion of fact to morality; innuendo. It's genteel, “not one of us” witch-hunting.

  2. This discussion thread from Coyne's site will interest you.