{"id":3961,"date":"2013-09-23T13:26:26","date_gmt":"2013-09-23T12:26:26","guid":{"rendered":"http:\/\/emilkirkegaard.dk\/en\/?p=3961"},"modified":"2014-10-09T18:51:39","modified_gmt":"2014-10-09T17:51:39","slug":"review-making-sense-of-heritability","status":"publish","type":"post","link":"https:\/\/emilkirkegaard.dk\/en\/2013\/09\/review-making-sense-of-heritability\/","title":{"rendered":"Review: Making sense of heritability"},"content":{"rendered":"

Download: http:\/\/www.libgen.net\/search.php?search_type=magic&search_text=making+sense+of+heritability&submit=Dig+for<\/p>\n

 <\/p>\n

This is a GREAT book, which goes down to the basics about heritability and the various claims people have made against it. Highly recommended. Best book of the 29 i have read this year.<\/p>\n

 <\/p>\n

The denial of genetically based psychological differences is the kind of sophisti-<\/span><\/p>\n

cated error normally accessible only to persons having Ph.D. degrees.<\/span><\/p>\n

David Lykken<\/span><\/p>\n

 <\/p>\n

Quote checks out. http:\/\/edge.org\/conversation\/-how-can-educated-continue-to-be-radical-environmentalists<\/a><\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

I was introduced to the nature\u2013nurture debate by reading Ned Block<\/span><\/p>\n

and Gerald Dworkin\u2019s well-known and widely cited anthology about<\/span><\/p>\n

the IQ controversy (Block & Dworkin 1976a). This collection of arti-<\/span><\/p>\n

cles has long been the main source of information about the heredity\u2013<\/span><\/p>\n

environment problem for a great number of scientists, philosophers, and<\/span><\/p>\n

other academics. It is not an exaggeration to say that the book has been<\/span><\/p>\n

the major in\ufb02uence on thinking about this question for many years. Like<\/span><\/p>\n

most readers, I also left the book with a feeling that hereditarianism (the<\/span><\/p>\n

view that IQ differences among individuals or groups are in substantial<\/span><\/p>\n

part due to genetic differences) is facing insuperable objections that strike<\/span><\/p>\n

at its very core.<\/span><\/p>\n

 <\/p>\n

There was something very satisfying, especially to philosophers, about<\/span><\/p>\n

the way hereditarianism was criticized there. A strong emphasis was on<\/span><\/p>\n

conceptual and methodological dif\ufb01culties, and the central arguments<\/span><\/p>\n

against hereditarianism appeared to have full destructive force indepen-<\/span><\/p>\n

dently of empirical data, which are, as we know, both dif\ufb01cult to evaluate<\/span><\/p>\n

and inherently unpredictable.<\/span><\/p>\n

 <\/p>\n

So this looked like a philosopher\u2019s dream come true: a scienti\ufb01c issue<\/span><\/p>\n

with potentially dangerous political implications was defused not through<\/span><\/p>\n

an arduous exploration of themessy empiricalmaterial but by using a dis-<\/span><\/p>\n

tinctly philosophical method of conceptual analysis and methodological<\/span><\/p>\n

criticism. It was especially gratifying that the undermined position was<\/span><\/p>\n

often associated with politically unacceptable views like racism, toler-<\/span><\/p>\n

ation of social injustice, etc. Besides, the defeat of that doctrine had a<\/span><\/p>\n

certain air of \ufb01nality. It seemed to be the result of very general, a priori<\/span><\/p>\n

considerations, which, if correct, could not be reversed by \u201cunpleasant\u201d<\/span><\/p>\n

discoveries in the future.<\/span><\/p>\n

 <\/p>\n

But very soon I started having second thoughts about Block and<\/span><\/p>\n

Dworkin\u2019s collection. The reasons are worth explaining in some detail<\/span><\/p>\n

I think, because the book is still having a considerable impact, especially<\/span><\/p>\n

on discussions in philosophy of science.<\/span><\/p>\n

 <\/p>\n

First, some of the arguments against hereditarianism presented there<\/span><\/p>\n

were just too successful. The refutations looked so utterly simple, elegant,<\/span><\/p>\n

and conclusive that it made me wonder whether competent scientists<\/span><\/p>\n

could have really defended a position that was somanifestly indefensible.<\/span><\/p>\n

Something was very odd about the whole situation.<\/span><\/p>\n

 <\/p>\n

 <\/p>\n

There is indeed something about this. This book is a premier case of what Weinberg called mentioned with his comment \u201c\u2026a knowledge of philosophy does not seem to be of use to physicists \u2013 always with the exception that the work of some philosophers helps us to avoid the errors of other philosophers.\u201d<\/p>\n

 <\/p>\n

See: http:\/\/www.abstractdelights.com\/no-respect<\/a><\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

Of course,Bouchardwould be justi\ufb01ed in notworrying toomuch about<\/span><\/p>\n

these global methodological criticisms if the only people who made a<\/span><\/p>\n

fuss over them were philosophers of science. Even with this unfriendly<\/span><\/p>\n

stance becoming a consensus in philosophy of science, scientists might<\/span><\/p>\n

still remain unimpressed because many of them would probably be sym-<\/span><\/p>\n

pathetic to JamesWatson\u2019s claim: \u201cI do not like to suffer at all from what<\/span><\/p>\n

I call the German disease, an interest in philosophy\u201d (Watson 1986: 19).<\/span><\/p>\n

 <\/p>\n

Source is: Watson, J. D. 1986, \u201cBiology: A Necessarily Limitless Vista,\u201d in S. Rose and L.<\/p>\n

Appignanesi (eds.), Science and Beyond, Oxford, Blackwell.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

At this point I am afraid I may lose some of my scienti\ufb01c readers.<\/span><\/p>\n

Remembering Steven Weinberg\u2019s statement that the insights of philoso-<\/span><\/p>\n

phers have occasionally bene\ufb01ted scientists, \u201cbut generally in a negative<\/span><\/p>\n

fashion \u2013 by protecting them from the preconceptions of other philoso-<\/span><\/p>\n

phers\u201d (Weinberg 1993: 107), they might conclude that it is best just to<\/span><\/p>\n

avoid reading any philosophy (including this book), and that in this way<\/span><\/p>\n

they will neither contract preconceptions nor need protection fromthem.<\/span><\/p>\n

But the problemis that the preconceptions discussed here do not originate<\/span><\/p>\n

from a philosophical armchair. Scientists should be aware that to a great<\/span><\/p>\n

extent these preconceptions come from some of their own. Philosophers<\/span><\/p>\n

of science uncritically accepted these seductive but ultimately fallacious<\/span><\/p>\n

arguments from scientists, repackaged them a little, and then fed them<\/span><\/p>\n

back to the scienti\ufb01c community, which often took them very seriously.<\/span><\/p>\n

Bad science was mistaken for good philosophy.<\/span><\/p>\n

 <\/p>\n

Sesardic clearly saw the same connection to Weinberg\u2019s comments as i did. :)<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

It may seem surprising that Jones dismissed the views of the founder<\/span><\/p>\n

of his own laboratory (Galton Laboratory, University College London)<\/span><\/p>\n

in such amanner. But then again this should perhaps not be so surprising.<\/span><\/p>\n

One can hardly be expected to study seriously the work of a man whom<\/span><\/p>\n

one happens to call publicly \u201cVictorian racist swine\u201d \u2013 the way Jones<\/span><\/p>\n

referred to Galton in an interview (Grove 1991). Also, in Jones\u2019s book<\/span><\/p>\n

Genetics for Beginners (Jones & Van Loon 1993: 169), Galton is pictured<\/span><\/p>\n

in a Nazi uniform, with a swastika on his sleeve.<\/span><\/p>\n

 <\/p>\n

The virulent antinazism among these lefties is extraordinary. It targets everybody having the least to do with ideas the nazis also liked. It is a wonder no one attacks vegetarians or people who campaign against smoking for being nazis…<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

Arthur Jensen once said that \u201ca heritability study may be regarded<\/span><\/p>\n

as a Geiger counter with which one scans the territory in order to \ufb01nd<\/span><\/p>\n

the spot one can most pro\ufb01tably begin to dig for ore\u201d (Jensen 1972b:<\/span><\/p>\n

243). That Jensen\u2019s advice as to how to look upon heritability is merely<\/span><\/p>\n

an application of a standard general procedure in causal reasoning is<\/span><\/p>\n

con\ufb01rmed by the following observation from an introduction to causal<\/span><\/p>\n

analysis: \u201cthe decomposition of statistical associations represents a \ufb01rst<\/span><\/p>\n

step. The results indicate which effects are important and which may be<\/span><\/p>\n

safely ignored, that is, where we ought to start digging in order to uncover<\/span><\/p>\n

the nature of the causal mechanisms producing association between our<\/span><\/p>\n

variables\u201d (Hellevik 1984: 149). High heritability of a trait (in a given<\/span><\/p>\n

population) often signals that it may be worthwhile to dig further, in the<\/span><\/p>\n

sense that an important geneticmechanismcontrolling differences in this<\/span><\/p>\n

trait may thus be uncovered.8<\/span><\/p>\n

 <\/p>\n

Another great Jensen insight.<\/p>\n

 <\/p>\n

Citation is to: 1972b, \u201cDiscussion,\u201d in L. Ehrman, G. S. Omenn, E. Caspari (eds.), Genetics,<\/p>\n

Environment and Behavior, New York, Academic Press.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

Second, even if a trait is shared by all organisms in a given population<\/span><\/p>\n

it can still be heritable \u2013 if we take a broader perspective, and compare<\/span><\/p>\n

that populationwith other populations. The critics of heritability are often<\/span><\/p>\n

confused, and switch from one perspective to another without noticing it.<\/span><\/p>\n

Consider the following \u201cproblem\u201d for heritability:<\/span><\/p>\n

 <\/p>\n

the heritability of \u201cwalking on two legs\u201d is zero.And yetwalking on two legs<\/em><\/span><\/p>\n

is clearly a fundamental property of being human, and is one of the more<\/em><\/span><\/p>\n

obvious biological differences between humans and other great apes such<\/em><\/span><\/p>\n

as chimpanzees or gorillas. It obviously depends heavily on genes, despite<\/em><\/span><\/p>\n

having a heritability of zero. (Bateson 2001b: 565; cf. Bateson 2001a: 150\u2013<\/em><\/span><\/p>\n

151; 2002: 2212)<\/em><\/span><\/p>\n

 <\/p>\n

When Bateson speaks about the differences between humans and other<\/span><\/p>\n

great apes, the heritability of walking on two legs in that population<\/span><\/p>\n

(consisting of humans, chimpanzees, and gorillas) is certainly not zero.<\/span><\/p>\n

On the other hand, within the human species itself the heritability may<\/span><\/p>\n

well be zero. So, if it is just made entirely clear which population is<\/span><\/p>\n

being discussed, no puzzling element remains. In the narrower popula-<\/span><\/p>\n

tion (humans), the question \u201cDo genetic differences explain why some<\/span><\/p>\n

people walk on two legs and some don\u2019t?\u201d has a negative answer because<\/span><\/p>\n

there are no such genetic differences. In the broader population (humans,<\/span><\/p>\n

chimpanzees, and gorillas) the question \u201cDo genetic differences explain<\/span><\/p>\n

why some organisms walk on two legs and some don\u2019t?\u201d has an af\ufb01rma-<\/span><\/p>\n

tive answer. All this neatly accords with the logic of heritability, and cre-<\/span><\/p>\n

ates no problem whatsoever. The critics of hereditarianism like to repeat<\/span><\/p>\n

that heritability is a population-relative statistic, but when they raise this<\/span><\/p>\n

kind of objection it seems that they themselves forget this important<\/span><\/p>\n

truth.<\/span><\/p>\n

 <\/p>\n

Things like the number of finger is also heritable within populations. There are rare genetic mutations that cause supernumerary body parts: https:\/\/en.wikipedia.org\/wiki\/Supernumerary_body_part<\/a><\/p>\n

 <\/p>\n

However, these are very rare, so to spot them, one needs a huge sample size. Surely the heritability of having 6 fingers is high, while the heritability of having 4 fingers is low, but not zero. Of the people who have 4 fingers, most of the casesare probably caused by unique environment (i.e. accidents), but some are caused by genetics.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

(4) It is often said that in individual cases it is meaningless to compare<\/span><\/p>\n

the importance of interacting causes: \u201cIf an event is the result of the joint<\/span><\/p>\n

operation of a number of causative chains and if these causes \u2018interact\u2019<\/span><\/p>\n

in any generally accepted meaning of the word, it becomes conceptually<\/span><\/p>\n

impossible to assign quantitative values to the causes of that individual<\/span><\/p>\n

event\u201d (Lewontin 1976a: 181).But this is in fact not true.Take, for example,<\/span><\/p>\n

the rectangle with width 2 and length 1 (from Figure 2.3). Its area is 2,<\/span><\/p>\n

which is considerably below the average area for all rectangles (around<\/span><\/p>\n

100). Why is that particular rectangle smaller than most others? Is its<\/span><\/p>\n

width or its length more responsible for that? Actually, this question is<\/span><\/p>\n

not absurd at all. It has a straightforward and perfectlymeaningful answer.<\/span><\/p>\n

The rectangleswith thatwidth (2) have on average the area that is identical<\/span><\/p>\n

to the mean area for all rectangles (100.66), so the explanation why the<\/span><\/p>\n

area of that particular rectangle deviates so much from the mean value<\/span><\/p>\n

cannot be in its width. It is its below-average length that is responsible.<\/span><\/p>\n

 <\/p>\n

Even the usually cautious David Lykken slips here by condemning<\/span><\/p>\n

the measurement of causal in\ufb02uences in the individual case as inherently<\/span><\/p>\n

absurd: \u201cIt is meaningless to ask whether Isaac Newton\u2019s genius was due<\/span><\/p>\n

more to his genes or his environment, as meaningless as asking whether<\/span><\/p>\n

the area of a rectangle is due more to its length or its width\u201d (Lykken<\/span><\/p>\n

1998a: 24). Contrary to what he says, however, it makes perfect sense to<\/span><\/p>\n

inquire whether Newton\u2019s extraordinary contributions were more due to<\/span><\/p>\n

his above-average inherited intellectual ability or to his being exposed<\/span><\/p>\n

to an above-average stimulating intellectual environment (or to some<\/span><\/p>\n

particular combination of the two). The Nuf\ufb01eld Council on Bioethics<\/span><\/p>\n

makes a similar mistake in its report on genetics and human behavior:<\/span><\/p>\n

\u201cIt is vital to understand that neither concept of heritability [broad or<\/span><\/p>\n

narrow] allows us to conclude anything about the role of heredity in the<\/span><\/p>\n

development of a characteristic in an individual\u201d (Nuf\ufb01eld 2002: 40). On<\/span><\/p>\n

the contrary, if the broad heritability of a trait is high, this does tell us<\/span><\/p>\n

that any individual\u2019s phenotypic divergence from the mean is probably<\/span><\/p>\n

more caused by a non-standard genetic in\ufb02uence than by a non-typical<\/span><\/p>\n

environment. For a characteristically clear explanation of why gauging<\/span><\/p>\n

the contributions of heredity and environment is not meaningless even in<\/span><\/p>\n

an individual case, see Sober 1994: 190\u2013192.<\/span><\/p>\n

 <\/p>\n

This is a good point. The reason not to talk about the causes of a particular level of g<\/em> in some person is not that it is a meaningless question, it is that it is difficult to know the answer. But in some cases, it is clearly possible, cf. my number of fingers scenario above.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

Nesardic mentions two studies that fysical attractiveness is not<\/em> correlated with intelligence. That goes against what i believe(d?). He cites:<\/p>\n

 <\/p>\n

Feingold, A. 1992, \u201cGood-looking People Are NotWhatWe Think,\u201d Psycholog-<\/p>\n

ical Bulletin 111: 304\u2013341.<\/p>\n

 <\/p>\n

Langlois, J. H., Kalakanis, L., Rubenstein, A. J., Larson, A., Hallam, M., and<\/p>\n

Smoot, M. 2000, \u201cMaxims or Myths of Beauty? A Meta-Analytic and Theo-<\/p>\n

retical Review,\u201d Psychological Bulletin 126: 390\u2013423.<\/p>\n

http:\/\/emilkirkegaard.dk\/en\/wp-content\/uploads\/Maxims-or-Myths-of-Beauty.pdf<\/a><\/p>\n

 <\/p>\n

But i apparently dont have access to the first one. But the second one i do have. In it one can read:<\/p>\n

 <\/p>\n

According to this maxim, there is no necessary correspondence<\/span><\/p>\n

between external appearance and the behavior or personality of an<\/span><\/p>\n

individual (Ammer, 1992). Two meta-analyses have examined the<\/span><\/p>\n

relation between attractiveness and some behaviors and traits<\/span><\/p>\n

(Feingold, 1992b2; L. A. Jackson, Hunter, & Hodge, 1995). Fein-<\/span><\/p>\n

gold (1992b) reported significant relations between attractiveness<\/span><\/p>\n

and measures of mental health, social anxiety, popularity, and<\/span><\/p>\n

sexual activity but nonsignificant relations between attractiveness<\/span><\/p>\n

and sociability, internal locus of control, freedom from self-<\/span><\/p>\n

absorption and manipulativeness, and sexual permissiveness in<\/span><\/p>\n

adults. Feingold also found a nonsignificant relation between at-<\/span><\/p>\n

tractiveness and intelligence (r = .04) for adults, whereas L. A.<\/span><\/p>\n

Jackson et al. found a significant relation for both adults (d = .24<\/span><\/p>\n

overall, d = .02 once selected studies were removed) and for<\/span><\/p>\n

children (d = .41).<\/span><\/p>\n

 <\/p>\n

These meta-analyses suggest that there may be a relation be-<\/span><\/p>\n

twe^n behavior and attractiveness, but the inconsistencies in re-<\/span><\/p>\n

sults call for additional attention. Moreover, the vast majority of<\/span><\/p>\n

dependent variables analyzed by Feingold (1992b) and L. A.<\/span><\/p>\n

Jackson et al. (1995) assessed traits as defined by psychometric<\/span><\/p>\n

tests (e.g., IQ) rather than behavior as defined by observations of<\/span><\/p>\n

behaviors in actual interactions. Thus, to fully understand the<\/span><\/p>\n

relations among appearance, behaviors, and traits, it is important to<\/span><\/p>\n

broaden the conception of behavior beyond that used by Feingold<\/span><\/p>\n

and L. A. Jackson et al. If beauty is only skin-deep, then a<\/span><\/p>\n

comprehensive meta-analysis of the literature should find no sig-<\/span><\/p>\n

nificant differences between attractive and unattractive people in<\/span><\/p>\n

their behaviors, traits, or self-views.<\/span><\/p>\n

 <\/p>\n

So, maybe. It seems difficult that g<\/em> and pa<\/em> (phy. attract.) is NOT associated purely by effect of mating choices, since females prefer males with high SES and males prefer females with have pa<\/em>. Then comes the mutational load hypothesis, and the fact that smarter people presumably are better at taking care of their bodies, which increases pa<\/em>. I find it very difficult indeed to believe that they arent correlated.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

In my opinion, this kind of deliberate misrepresentation in attacks on<\/span><\/p>\n

hereditarianism is less frequent than sheer ignorance. But why is it that a<\/span><\/p>\n

number of peoplewho publicly attack \u201cJensenism\u201d are so poorly informed<\/span><\/p>\n

about Jensen\u2019s real views? Given the magnitude of their distortions and<\/span><\/p>\n

the ease with which these misinterpretations spread, one is alerted to<\/span><\/p>\n

the possibility that at least some of these anti-hereditarians did not get<\/span><\/p>\n

their information about hereditarianism\ufb01rst hand, fromprimary sources,<\/span><\/p>\n

but only indirectly, from the texts of unsympathetic and sometimes quite<\/span><\/p>\n

biased critics.8In this connection, it is interesting to note that several<\/span><\/p>\n

authors who strongly disagree with Jensen (Longino 1990; Bowler 1989;<\/span><\/p>\n

Allen 1990; Billings et al. 1992; McInerney 1996; Beckwith 1993; Kassim<\/span><\/p>\n

2002) refer to his classic paper from 1969 by citing the volume of the<\/span><\/p>\n

Harvard Educational Review incorrectly as \u201c33\u201d (instead of \u201c39\u201d). What<\/span><\/p>\n

makes this mis-citation noteworthy is that the very same mistake is to<\/span><\/p>\n

be found in Gould\u2019s Mismeasure of Man (in both editions). Now the<\/span><\/p>\n

fact that Gould\u2019s idiosyncratic lapsus calami gets repeated in the later<\/span><\/p>\n

sources is either an extremely unlikely coincidence or else it reveals that<\/span><\/p>\n

these authors\u2019 references to Jensen\u2019s paper actually originate from their<\/span><\/p>\n

contact with Gould\u2019s text, not Jensen\u2019s.<\/span><\/p>\n

 <\/p>\n

Gotcha. A nice illustrating case of the thing map makers used to use to prove plagiarism. https:\/\/en.wikipedia.org\/wiki\/Copyright_trap<\/a><\/p>\n

 <\/p>\n

Incidentally, in this case it ended up having another use! :)<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

Nesardic quotes:<\/p>\n

 <\/p>\n

In December 1986 our newly-born daughter was diagnosed to be suffering<\/em><\/p>\n

from a genetically caused disease called Dystrophic Epidermolysis Bullosa<\/em><\/p>\n

(EB). This is a disease in which the skin of the sufferer is lacking in certain<\/em><\/p>\n

essential \ufb01bers. As a result, any contact with her skin caused large blisters<\/em><\/p>\n

to form, which subsequently burst leaving raw open skin that healed only<\/em><\/p>\n

slowly and left terrible scarring. As EB is a genetically caused disease it<\/em><\/p>\n

is incurable and the form that our daughter suffered from usually causes<\/em><\/p>\n

death within the \ufb01rst sixmonths of life . . .Our daughter died after a painful<\/em><\/p>\n

and short life at the age of only 12 weeks. (quoted in Glover 2001: 431 \u2013<\/em><\/p>\n

italics added)<\/em><\/p>\n

 <\/p>\n

from: Glover, J. 2001, \u201cFuture People, Disability, and Screening,\u201d in J. Harris (ed.),<\/p>\n

Bioethics, Oxford, Oxford University Press.<\/p>\n

 <\/p>\n

Nasty disease indeed. Only eugenics can avoid such atrocities.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

On the contrary, empirical evidence suggests that for many important<\/span><\/p>\n

psychological traits (particularly IQ), the environmental in\ufb02uences that<\/span><\/p>\n

account for phenotypic variation among adults largely belong to the non-<\/span><\/p>\n

shared variety. In particular, adoption studies of genetically unrelated<\/span><\/p>\n

children raised in the same family show that for many traits the adult<\/span><\/p>\n

phenotypic correlation among these children is very close to zero (Plomin<\/span><\/p>\n

et al. 2001: 299\u2013300). This very surprising but consistent result points<\/span><\/p>\n

to the conclusion that we may have greatly overestimated the impact<\/span><\/p>\n

of variation in shared environmental in\ufb02uences.6The fact that variation<\/span><\/p>\n

within a normal range does not have much effect was dramatized in the<\/span><\/p>\n

following way by neuroscientist Steve Petersen:<\/span><\/p>\n

 <\/p>\n

At a minimum, development really wants to happen. It takes very impov-<\/em><\/span><\/p>\n

erished environments to interfere with development because the biological<\/em><\/span><\/p>\n

system has evolved so that the environment alone stimulates development.<\/em><\/span><\/p>\n

What does this mean? Don\u2019t raise your children in a closet, starve them, or<\/em><\/span><\/p>\n

hit them in the head with a frying pan. (Quoted in Bruer 1999: 188)<\/em><\/span><\/p>\n

 <\/p>\n

But if social reforms are mainly directed at eliminating precisely these<\/span><\/p>\n

between-family inequalities (economic, social, and educational), and if<\/span><\/p>\n

these differences are not so consequential as we thought, then egalitar-<\/span><\/p>\n

ianism will \ufb01nd a point of resistance not just in genes but also in the<\/span><\/p>\n

non-heritable domain, i.e., in those uncontrollable and chaotically emerg-<\/span><\/p>\n

ing environmental differences that by their very nature cannot be an easy<\/span><\/p>\n

object for social manipulation.<\/span><\/p>\n

 <\/p>\n

All this shows that it is irresponsible to disregard constraints on mal-<\/span><\/p>\n

leability and fan false hopes about what social or educational reforms can<\/span><\/p>\n

do. As David Rowe said:<\/span><\/p>\n

 <\/p>\n

As social scientists, we should be wary of promisingmore than we are likely<\/em><\/span><\/p>\n

to deliver. Physicists do not greet every new perpetual motion machine,<\/em><\/span><\/p>\n

created by a basement inventor, with shouts of joy and claims of an endless<\/em><\/span><\/p>\n

source of electrical or mechanical power; no, they know the laws of physics<\/em><\/span><\/p>\n

would prevent it. (Rowe 1997: 154)<\/em><\/span><\/p>\n

 <\/p>\n

I will end this chapter with another quali\ufb01cation.Although heritability<\/span><\/p>\n

puts constraints on malleability it is, strictly speaking, incorrect to say<\/span><\/p>\n

that the heritable part of phenotypic variance cannot be decreased by<\/span><\/p>\n

environmentalmanipulation. It is true that if heritability is, say, 80 percent<\/span><\/p>\n

then at most 20 percent of the variation can be eliminated by equalizing<\/span><\/p>\n

environments. But if we consider redistributing environments, without<\/span><\/p>\n

necessarily equalizing them, a larger portion of variance than 20 percent<\/span><\/p>\n

can be removed.<\/span><\/p>\n

 <\/p>\n

Table 5.5 gives an illustration how this might work.<\/span><\/p>\n

In this examplewith just two genotypes and two environments (equally<\/span><\/p>\n

distributed in the population), themain effect of the genotype on the vari-<\/span><\/p>\n

ation in the trait (say, IQ) is obviously stronger than the environmental<\/span><\/p>\n

effect. Going from G2 to G1 increases IQ 20 points, while going from the<\/span><\/p>\n

less favorable environment (E2) to the more favorable one (E1) leads<\/span><\/p>\n

to an increase of only 10 points. Heritability is 80 percent, the genetic<\/span><\/p>\n

variance being 100 and the environmental variance being 25. Now if we<\/span><\/p>\n

expose everyone to the more favorable environment (E1) we will com-<\/span><\/p>\n

pletely remove the environmental variance (25), and the variance in the<\/span><\/p>\n

new population will be 100. The genetic variance survives environmental<\/span><\/p>\n

manipulation unscathed.<\/span><\/p>\n

 <\/p>\n

Table:<\/span><\/p>\n

http:\/\/emilkirkegaard.dk\/en\/wp-content\/uploads\/ScreenHunter_90-Sep.-23-13.57.png<\/span><\/a><\/p>\n

 <\/p>\n

But there is a way to make an incursion into the \u201cgenetic territory.\u201d<\/span><\/p>\n

Suppose we expose all those endowed with G1 to the less favorable<\/span><\/p>\n

environment (E2) and those with G2 to the more favorable environment<\/span><\/p>\n

(E1). In this way we would get rid of the highest and lowest score, and<\/span><\/p>\n

we would be left only with scores of 95 and 105. In terms of variance, we<\/span><\/p>\n

would have succeeded in eliminating 80 percent of variance by manipu-<\/span><\/p>\n

lating environment, despite heritability being 80 percent.<\/span><\/p>\n

 <\/p>\n

How is this possible? The answer is in the formula for calculating vari-<\/span><\/p>\n

ance in chapter 1 (see p. 21). One component of variance is genotype\u2013<\/span><\/p>\n

environment correlation, which can have a negative numerical value.<\/span><\/p>\n

This is what has happened in our example. The phenotype-increasing<\/span><\/p>\n

genotype was paired with the phenotype-decreasing environment, and<\/span><\/p>\n

the phenotype-decreasing genotype was paired with the phenotype-<\/span><\/p>\n

increasing environment. This move introduced the negative G\u2013E corre-<\/span><\/p>\n

lation and neutralized the main effects, bringing about a drastic drop in<\/span><\/p>\n

variation.<\/span><\/p>\n

 <\/p>\n

The strategy calls to mind the famous Kurt Vonnegut story \u201cHarrison<\/span><\/p>\n

Bergeron,\u201d where the society intervenes very early and suppresses the<\/span><\/p>\n

mere expression of superior innate abilities by imposing arti\ufb01cial obsta-<\/span><\/p>\n

cles on gifted individuals. Here is just one short passage from Vonnegut:<\/span><\/p>\n

 <\/p>\n

And George, while his intelligence was way above normal, had a little<\/em><\/span><\/p>\n

mental-handicap radio in his ear \u2013 he was required by law to wear it at all<\/em><\/span><\/p>\n

times. It was tuned to a government transmitter and, every twenty seconds<\/em><\/span><\/p>\n

or so, the transmitter would send out some sharp noise to keep people like<\/em><\/span><\/p>\n

George from taking unfair advantage of their brains. (Vonnegut 1970: 7)<\/em><\/span><\/p>\n

 <\/p>\n

We all get a chill from the nightmare world of \u201cHarrison Bergeron.\u201d But<\/span><\/p>\n

in its milder forms the idea that if the less talented cannot be brought<\/span><\/p>\n

up to the level of those better endowed, the latter should then be held<\/span><\/p>\n

back in their development for the sake of equality, is not entirely with-<\/span><\/p>\n

out adherents. In one of the most carefully argued sociological studies<\/span><\/p>\n

on inequality there is an interesting proposal in that direction, about<\/span><\/p>\n

how to reduce differences in cognitive abilities that are caused by genetic<\/span><\/p>\n

differences:<\/span><\/p>\n

 <\/p>\n

Asociety committed to achieving full cognitive equality would, for example,<\/em><\/span><\/p>\n

probably have to exclude genetically advantaged children from school. It<\/em><\/span><\/p>\n

might also have to impose other handicaps on them, like denying them<\/em><\/span><\/p>\n

access to books and television. Virtually no one thinks cognitive equality<\/em><\/span><\/p>\n

worth such a price.Certainlywe do not.But if our goalwere simply to reduce<\/em><\/span><\/p>\n

cognitive inequality to, say, half its present level, instead of eliminating it<\/em><\/span><\/p>\n

entirely, the pricemight bemuch lower. (Jencks et al. 1972: 75\u201376 \u2013 emphasis<\/em><\/span><\/p>\n

added)<\/em><\/span><\/p>\n

 <\/p>\n

So although Jencks and his associates concede that excluding geneti-<\/span><\/p>\n

cally advantaged children from school and denying them access to books<\/span><\/p>\n

may be too drastic, they appear to think that the price of equality could<\/span><\/p>\n

become acceptable if the goalwas lowered andmeasuresmademoremod-<\/span><\/p>\n

erate. Are they suggesting that George keeps the little mental-handicap<\/span><\/p>\n

radio in his ear but that the noise volume should be set only at half<\/span><\/p>\n

volume?<\/span><\/p>\n

 <\/p>\n

I wonder if someone cud make a good video based on this… Oh that’s right…<\/p>\n

 <\/p>\n

https:\/\/www.youtube.com\/watch?v=F1eHkbmUJBQ<\/a><\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

David Lykken had a good comment on this tendency of some<\/span><\/p>\n

Darwinians (he had John Tooby and Leda Cosmides in mind) to pub-<\/span><\/p>\n

licly dissociate themselves from behavior genetics, in the hope that this<\/span><\/p>\n

move would make their own research less vulnerable to political criti-<\/span><\/p>\n

cisms: \u201cAre these folks just being politic, just claiming only the minimum<\/span><\/p>\n

they need to pursue their own agenda while leaving the behavior geneti-<\/span><\/p>\n

cists to contend with the main armies of political correctness?\u201d (Lykken<\/span><\/p>\n

1998b).<\/span><\/p>\n

 <\/p>\n

There are some obvious, and other less obvious, consequences of polit-<\/span><\/p>\n

ically inspired, vituperative attacks on a given hypothesisH.On the obvi-<\/span><\/p>\n

ous side, many scientists who believe that H is true will be reluctant to<\/span><\/p>\n

say so, many will publicly condemn it in order to eliminate suspicion that<\/span><\/p>\n

they might support it, anonymous polls of scientists\u2019 opinions will give<\/span><\/p>\n

a different picture from the most vocal and most frequent public pro-<\/span><\/p>\n

nouncements (Snyderman & Rothman 1988), it will be dif\ufb01cult to get<\/span><\/p>\n

funding for research on \u201csensitive\u201d topics,19the whole research area will<\/span><\/p>\n

be avoided by many because one could not be sure to end up with the<\/span><\/p>\n

\u201cright\u201d conclusion,20texts insuf\ufb01ciently critical of \u201ccondemned\u201d views<\/span><\/p>\n

will not be accepted for publication,21etc.<\/span><\/p>\n

 <\/p>\n

On the less obvious side, a nasty campaign against H could have the<\/span><\/p>\n

unintended effect of strengthening H epistemically, and making the criti-<\/span><\/p>\n

cism of H look less convincing. Simply, if you happen to believe that H is<\/span><\/p>\n

true and if you also know that opponents of H will be strongly tempted<\/span><\/p>\n

to \u201cplay dirty,\u201d that they will be eager to seize upon your smallest mis-<\/span><\/p>\n

take, blow it out of all proportion, and label you with Dennett\u2019s \u201cgood<\/span><\/p>\n

epithets,\u201d with a number of personal attacks thrown in for good measure,<\/span><\/p>\n

then if you still want to advocate H, you will surely take extreme care to<\/span><\/p>\n

present your argument in the strongest possible form. In the inhospitable<\/span><\/p>\n

environment for your views, you will be aware that any major error is a<\/span><\/p>\n

liability that you can hardly afford, because it willmore likely be regarded<\/span><\/p>\n

as a re\ufb02ection of your sinister political intentions than as a sign of your<\/span><\/p>\n

fallibility. The last thing onewants in this situation is the disastrous combi-<\/span><\/p>\n

nation of being politically denounced (say, as a \u201cracist\u201d) and being proved<\/span><\/p>\n

to be seriously wrong about science. Therefore, in the attempt to make<\/span><\/p>\n

themselves as little vulnerable as possible to attacks they can expect from<\/span><\/p>\n

their uncharitable and strident critics, those who defendHwill tread very<\/span><\/p>\n

cautiously and try to build a very solid case before committing themselves<\/span><\/p>\n

publicly. As a result, the quality of their argument will tend to rise, if the<\/span><\/p>\n

subject matter allows it.22<\/span><\/p>\n

 <\/p>\n

Interesting effects of the unpopularity of the views.<\/p>\n

 <\/p>\n

–<\/p>\n

 <\/p>\n

First of all, the issue about heritability is obviously a purely empirical<\/span><\/p>\n

and factual one. So there is a strong case for denying that it can affect<\/span><\/p>\n

our normative beliefs. But it is worth noting that the idea that a certain<\/span><\/p>\n

heritability value could have political implications was not only criticized<\/span><\/p>\n

for violatingHume\u2019s law, but also for being politically dangerous. Bluntly,<\/span><\/p>\n

if the high heritability of IQ differences between races really has racist<\/span><\/p>\n

implications then it would seem that, after all, science could actually dis-<\/span><\/p>\n

cover that racism is true.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

The dangerwas clearly recognized byDavidHorowitz in his comments<\/span><\/p>\n

on a statement on race that the Genetics Society of America (GSA)<\/span><\/p>\n

wanted to issue in 1975. A committee preparing the statement took the<\/span><\/p>\n

line that racism is best fought by demonstrating that racists\u2019 belief in the<\/span><\/p>\n

heritability of the black\u2013white difference in IQ is disproved by science.<\/span><\/p>\n

Horowitz objected:<\/span><\/p>\n

\u00a0<\/span><\/p>\n

The proposed statement is weak morally, for the following reason: Racists<\/em><\/span><\/p>\n

assert that blacks are genetically inferior in I.Q. and therefore need not<\/em><\/span><\/p>\n

be treated as equals. The proposed statement disputes the premise of the<\/em><\/span><\/p>\n

assertion, but not the logic of the conclusion. It does not perceive that the<\/em><\/span><\/p>\n

premise, while it may be mistaken, is not by itself racist: it is the conclusion<\/em><\/span><\/p>\n

drawn (wrongly) from it that is racist. Even if the premise were correct, the<\/em><\/span><\/p>\n

conclusion would not be justi\ufb01ed …Yetthe proposed statement directs its<\/em><\/span><\/p>\n

main \ufb01re at the premise, and by so doing seems to accept the racist logic.<\/em><\/span><\/p>\n

It places itself in a morally vulnerable position, for if, at some future time,<\/em><\/span><\/p>\n

that the premise is correct, then the whole GSA case collapses, together<\/em><\/span><\/p>\n

with its case for equal opportunity. (Quoted in Provine 1986: 880)<\/em><\/span><\/p>\n

\u00a0<\/span><\/p>\n

The same argument was made by others:<\/span><\/p>\n

\u00a0<\/span><\/p>\n

To rest the case for equal treatment of national or racial minorities on<\/em><\/span><\/p>\n

the assertion that they do not differ from other men is implicitly to admit<\/em><\/span><\/p>\n

that factual inequality would justify unequal treatment. (Hayek 1960:<\/em><\/span><\/p>\n

86)<\/em><\/span><\/p>\n

But to fear research on genetic racial differences, or the possible existence<\/em><\/span><\/p>\n

of a biological basis for differences in abilities, is, in a sense, to grant the<\/em><\/span><\/p>\n

racist\u2019s assumption: that if it should be established beyond reasonable doubt<\/em><\/span><\/p>\n

that there are biological or genetically conditioned differences in mental<\/em><\/span><\/p>\n

abilities among individuals or groups, then we are justi\ufb01ed in oppressing<\/em><\/span><\/p>\n

or exploiting those who are most limited in genetic endowment. This is, of<\/em><\/span><\/p>\n

course, a complete non sequitur. (Jensen 1972a: 329)<\/em><\/span><\/p>\n

If someone defends racial discrimination on the grounds of genetic differ-<\/em><\/span><\/p>\n

ences between races, it is more prudent to attack the logic of his argument<\/em><\/span><\/p>\n

than to accept the argument and deny any differences. The latter stance can<\/em><\/span><\/p>\n

leave one in an extremely awkward position if such a difference is subse-<\/em><\/span><\/p>\n

quently shown to exist. (Loehlin et al. 1975: 240)<\/em><\/span><\/p>\n

But it is a dangerousmistake to premise themoral equality of human beings<\/em><\/span><\/p>\n

on biological similarity because dissimilarity, once revealed, then becomes<\/em><\/span><\/p>\n

an argument for moral inequality. (Edwards 2003: 801)<\/em><\/span><\/p>\n

 <\/p>\n

Good point indeed.<\/p>\n","protected":false},"excerpt":{"rendered":"

Download: http:\/\/www.libgen.net\/search.php?search_type=magic&search_text=making+sense+of+heritability&submit=Dig+for   This is a GREAT book, which goes down to the basics about heritability and the various claims people have made against it. Highly recommended. Best book of the 29 i have read this year.   The denial of genetically based psychological differences is the kind of sophisti- cated error normally accessible only […]<\/p>\n","protected":false},"author":17,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1839,1879,1850,1935,1921],"tags":[2020,1067],"class_list":["post-3961","post","type-post","status-publish","format-standard","hentry","category-psychometics","category-education-politik","category-feminismequality","category-science-politik","category-sociology","tag-heritability","tag-review","entry"],"_links":{"self":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/3961","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/users\/17"}],"replies":[{"embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/comments?post=3961"}],"version-history":[{"count":2,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/3961\/revisions"}],"predecessor-version":[{"id":4380,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/3961\/revisions\/4380"}],"wp:attachment":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/media?parent=3961"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/categories?post=3961"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/tags?post=3961"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}