Discussions onGenius and Intelligence
Discussions onGenius and Intelligence    Mega Foundation Interview       with Arthur JensenChristopher Langan and Dr. Gina...
Mega Press                 Eastport, New York     Copyright © 2002 by Mega Foundation, Inc.         Published by Mega Foun...
Table of Contents     Forward     Question 1 - IQs of Famous Persons     Question 2 - g-loading Across Abilities     Quest...
Question 16 - Flynn Effect and Black IQ DistributionQuestion 17 - Regression and “Late Bloomers”Question 18 - Actualizing ...
ForwardArthur R. Jensen is a prominent educational psychologist whoreceived his PhD from Columbia in 1956. He did hispostd...
where it could be satisfactorily explored and challenged in thelight of day.    We contacted Dr. Jensen in May, 2001 and i...
Question #1Christopher Langan for the Mega Foundation: It is reportedthat one of this century’s greatest physicists, Nobel...
famous persons at all seriously. They are often fictitious andare used to make a point - typically a put-down of IQ test a...
talents or become known for socially significant intellectual orartistic achievements. This bare minimum threshold isproba...
without which they probably would not have becomegenerally recognized as scientific and inventive geniuses. So-called inte...
relationships. Two of these men knew each other very welland often discussed problems with each other. Each thoughtthe oth...
Question #2Chris Langan: For practical purposes, psychologists define“intelligence” as problem-solving ability. But there ...
to all mental abilities. “Mental abilities” is a more useful termand the various mental abilities measured by all sorts of...
g ability is necessary, though it may not be sufficient. A highlevel of some special ability combined with very low gdescr...
practical purposes, because they require individual testingwith special laboratory equipment and require a longertesting s...
intelligence is the discovery of the nature of this property ofthe brain that accounts for the empirical fact of g. It is ...
Question #3Chris Langan: As already observed, intelligence is the abilityto solve problems. But while one psychologist tal...
correspondences with Gardner, has he ever explicitlyrepudiated the mathematics of factor analysis?Arthur Jensen: It would ...
although it turns out that no tests known, so far, exclude somedegree of correlation with g. The g factor, however can bem...
musical instrument, for example, had an average IQ of 127.Does anyone want to bet that you could find a concertviolinist o...
interest to members of the Mega Foundation. This book alsoreinforces my view that eminence depends very much onother facto...
Question #4Chris Langan:     Given that intelligence is problem-solvingability, scant attention is paid to perhaps the mos...
Arthur Jensen: This is a very important point and it is mostimportant    in   the   up    bringing    and    development  ...
while others of comparable or even lesser intelligences maydo so. And those who do so in the extreme (e.g., Beethoven,Darw...
inculcate all the necessary qualities of the particularconstellation in any given individual picked on the basis ofjust on...
leading researcher on this topic is Professor Dean K. Simontonin his three fascinating books Scientific Genius, Greatness,...
Question #5Chris Langan: The study of neural networks suggests that assoon as we can explore the microscopic structure of ...
decades. And it will be possible to measure g physically interms of brain variables. The practical measurement ofabilities...
Question #6Chris   Langan:   Certain   high-ceiling   intelligence   tests,generically called “power tests”, are composed ...
Arthur Jensen: There are many power tests (i.e., non-speededor untimed tests) in psychometrics, although not of the kindde...
can only examine its products after the fact. At present, thereare much more tractable problems for research in the realm ...
Question #7Chris Langan: In science, theories and the definitionscomprising them are required to have models, and thesemod...
Arthur Jensen: This is a profound question and gets right atthe heart of many of the problems of psychology and makingit t...
measured in New York in the year 2050, just as we can saythat the average height of 18-year old male U.S. Army recruitsin ...
use for mind-body dualism. I think I was born opposed tothat notion.                           29
Question #8Chris Langan: As academic performance falls, there is agrowing tendency among educational theorists to claim th...
Arthur   Jensen:   The    purported    decline   in   academicperformance in schools and colleges is a terribly complexphe...
discover just how the required diversity can be accomplished.But each of the proposed approaches must be clearlydescribed ...
Question #9Chris Langan: The founders of Mensa, regarded by many asthe original high IQ club, complained that the group ha...
social change or carry out a large project with a unified aim.On the other hand, a group of persons with a wide range ofIQ...
is estimated that some 15 to 20 percent of the populationvariance in IQ is attributable to the effect of assortativemating...
Question #10Chris Langan:       Intelligence is about solving problems.Because problems consist of constraints to be satis...
main reason that a fairly high level of g acts as a threshold isthat to be creative in most fields, one has to master the ...
Question #11Chris Langan: Many people believe that genius and insanityare closely related. Indeed, history provides numero...
creativity. Psychoticism is not itself a psychiatric disorder ordisabling condition (although it is associated with a pron...
Question #12Chris Langan: Even IQ tests with moderate ceilings can beupwardly extrapolated, and there exist experimental h...
more meaningful and +4σ (IQ of 160) may well be the highestlevel in which we can have much confidence that it is g that is...
dependent on the possession of a fairly high level of g, in thesense of superior performance on the kinds of tests that ar...
or so above the average of U. C., Berkeley, undergraduates. Iwas interested in whether the Mensa subjects would alsoshow f...
Question #13Chris Langan: Intelligence is the ability to reason, i.e. to solveproblems. Problems are solved according to p...
Arthur Jensen: Yes, certainly. Various thinking or problem-solving algorithms can be trained and even automatizedthrough e...
tests. A test in algebra, for example, may be a poor way ofassessing g, but a good way to find out where a person standsin...
limited by an individual’s level of g. Before children areexposed to any kind of maths, for example, one can makefairly go...
Question #14Chris Langan: In The g Factor, you state (regarding the FlynnEffect) that “Whatever causes the rise in IQ, it ...
and IQ = 15z + 100]. The ratio IQ becomes increasingly suspectas children get older. It is based on the presumed (ordemons...
lower portion under the bell curve received more educationalattention and better education, and also probably better pre-a...
but were expressed as ranks, their rank order would coveyless information than the raw scores themselves. A true ratioscal...
Question #15Chris Langan: Why are IQs measured on relative scalesrather than in absolute terms? Saying that someone is bri...
that person stands with reference to some "normative" groupon the trait in question. A pediatrician can rather preciselyme...
with the g factor per se. A combination of such chronometricand physical variables will one day yield ratio-scale measures...
Question #16Chris Langan: On most IQ tests, ceiling effects begin to occurabove the two-sigma level. Thus, ceiling effects...
Arthur Jensen: This is a clever thought, although it hasbecome increasingly difficult to get IQ data on blacks, at leastin...
Question #17Chris Langan: It has been argued that the deviations from anormal curve that occur among child IQs are simply ...
Arthur Jensen: Yes, the variation in IQ (or relative standing insome normative group) as individuals grow up from aboutage...
Question #18Chris Langan: It seems that research on the profoundly giftedhas not only been very limited, but that virtuall...
fully utilize their potential nor rewarded in proportion to theirabilities. One might expect this to detract from theirent...
even more so in our modern technological society than in themore agrarian past. Higher IQ is always an advantage in themul...
Question #19Chris Langan: Aside from social ineptitude, perhaps the traitmost    often   associated    with   IQ    >   +4...
on the survivors of academic bureaucracy to solve our mosturgent problems. Unfortunately, academic politics is not avalid ...
IQ or level of education, Id pick the IQ, assuming the jobdoesnt require some specialized skills that can only beacquired ...
Question #20Chris Langan: In working with some of the profoundlygifted, Ive encountered a few hints about how theirextraor...
college with classmates who are six or seven years older. Thechanneling that takes place in college and thereafter in thew...
large majority of these "Termanites" became fairly ordinaryadults and some were less successful in life than are manyperso...
Question #21Chris Langan: As students, doctors and lawyers take tests likethe LSAT, their average IQs are found to be arou...
do such research. There are plenty of anecdotes that one hearsof, but I havent come across any bona fide research studiest...
any studies that can provide a more definite answer to yourquestion. But the issue is so contaminated by the need forpolit...
Question #22Chris Langan: The “generality” of g reflects the fact that g isfound      in     conjunction   with   every   ...
those who, being more enamored of political correctness thancommon sense, deny the existence of g despite its scientificba...
Question #23Chris Langan: With each passing year, it seems that popularculture places a lower value on high intelligence. ...
the conditions of Third World countries. The advancing frontof future civilization may well gravitate eastwardly. I cantsa...
Question #24Chris Langan: There is a certain amount of evidencesupporting the hypothesis that intelligent people, being be...
nothing about it. But a dysgenic trend that affects the overalllevel of g in the society would have ill-fated consequences...
Question #25Chris Langan: Modern civilization grows increasinglydependent on complex technology, and thus on people withth...
even the lower one-third) of the IQ distribution, as we knowits mental capabilities today, will have a hard time findingga...
Question #26Chris Langan: For some time now, Robert Plomin has beenlocating genes associated with high IQ. The evolution o...
progressing at an accelerating rate as the technology foridentifying differences in specific sections of DNA (notnecessari...
Plomins effort, I believe, is one of the most worthwhilepursuits in present-day behavioral science.                       ...
Question #27Chris Langan: It was suggested some time ago thatpharmacological methods, e.g. neurotransmitter loading,could ...
from generation to generation, whereas the chemical effectsmust be continually reinstated anew in every generation. In ape...
Question #28Chris Langan: Because genetic testing and engineering costsmoney, only the wealthy can easily afford it. This ...
nots" in this country, to say nothing of the world at large, is, Ifear, already great enough to be "a potential threat to ...
Question #29Chris Langan: Just as the human brain excels at certainintellectual tasks, computers excel at solving other ki...
Question #30Chris Langan: As far as the evidence is concerned, theexistence of g is scientifically indisputable. But let’s...
Arthur Jensen: I sense a growing tendency in our society infavor of treating all persons as individuals, and I believe tha...
Question #31Chris Langan: You’re working on a new book. Can youplease tell us briefly what the working title is and what i...
previous question regarding measurement problems, I believewe must measure individual differences in mental abilities byme...
Chronometric variables are fare more sensitive to subtle drugeffects than are any psychometric tests. Chronometricmethods ...
Christopher Langan and Gina LoSassoAbout the Mega FoundationChristopher     Michael Langan was identified as “severelygift...
Genius intelligents
Genius intelligents
Genius intelligents
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Genius intelligents

  1. 1. Discussions onGenius and Intelligence
  2. 2. Discussions onGenius and Intelligence Mega Foundation Interview with Arthur JensenChristopher Langan and Dr. Gina LoSasso and Members of the Mega Foundation, Mega International and the Ultranet Eastport, New York Mega Press 2002
  3. 3. Mega Press Eastport, New York Copyright © 2002 by Mega Foundation, Inc. Published by Mega Foundation, Inc. P. O. Box 894 Eastport, NY 11941 http://www.MegaPress.org Mega Press and Mega Foundation Press are trademarks of the Mega Foundation, Inc. All rights reserved. No part of this publication may be reproduced or transmitted, in any form or by any means, electronic, mechanical, photocopying, recorded, or otherwise, without the prior permission of the Mega Foundation.Graphic design and book layout by Gina Lynne LoSasso
  4. 4. Table of Contents Forward Question 1 - IQs of Famous Persons Question 2 - g-loading Across Abilities Question 3 - Multiple Intelligences Question 4 - Real World Problem-Solving Question 5 - Physiological Basis of g Question 6 - Power Tests Question 7 - Mind-Body Connection Question 8 - Scholastic Achievement Question 9 - High IQ Societies Question 10 - Creativity and IQ Question 11 - Genius and Insanity Question 12 - The Upper Limit of IQ Question 13 - Problem-Solving Algorithms Question 14 - Flynn Effect and IQ Measurement Question 15 - Relative vs. Absolute Measures
  5. 5. Question 16 - Flynn Effect and Black IQ DistributionQuestion 17 - Regression and “Late Bloomers”Question 18 - Actualizing IQ PotentialQuestion 19 - Financial Success and HumanitarianismQuestion 20 - Falling Through the CracksQuestion 21 - IQ and Professional CompetencyQuestion 22 - The Existence of the g-FactorQuestion 23 - Intellectual DegeneracyQuestion 24 - Dysgenic TrendsQuestion 25 – Eugenics and Social StructureQuestion 26 - IQ GenesQuestion 27 - Smart DrugsQuestion 28 - Genetic EngineeringQuestion 29 - BiocyberneticsQuestion 30 – Minorities and QuotasQuestion 31 - Mental ChronometryAbout the Mega FoundationAbout Mega Press
  6. 6. ForwardArthur R. Jensen is a prominent educational psychologist whoreceived his PhD from Columbia in 1956. He did hispostdoctoral research in London with Hans J. Eysenck, authorof the absorbing HIQ must-read Genius: The Natural History ofCreativity. Jensen is best known for a very controversial essayon genetic heritage that was first published in the February,1969 issue of the Harvard Educational Review, in which hisresearch on individual differences in intelligence led him toconclude that intelligence is 80% due to heredity and 20% dueto environmental influences. Even more controversial werehis findings regarding robust and replicable ethnic differencesin fluid intelligence. Coming on the heels of Herrnstein &Murrays controversial bestseller The Bell Curve, the extremelywell-conceived and well-executed research findings thatJensen revealed in The g Factor: The Science of Mental Ability(1998) finally moved the heritability debate into an arena
  7. 7. where it could be satisfactorily explored and challenged in thelight of day. We contacted Dr. Jensen in May, 2001 and introduced himto the Mega Foundation, our work, and our communities,asking him if we might forward to him a few of our members’questions on the topic of intelligence. Although he was in theprocess of writing a new book, Dr. Jensen very kindly tookthe time out of his busy schedule to answer all of ourquestions. (Special thanks to Dr. Robert N. Seitz, AndreaLobel, Bob Williams and our other members, for contributingquestions, ideas and feedback.) This extensive and fascinatinginterview, as transcribed by Kelly Self and edited byChristopher Langan and Dr. Gina LoSasso, was excerpted inNoesis-E prior to its publication of this electronic book. Thosewho wish to print out the interview may prefer the single-spaced excerpts available at the UltraHIQ website.
  8. 8. Question #1Christopher Langan for the Mega Foundation: It is reportedthat one of this century’s greatest physicists, Nobelist RichardFeynman, had an IQ of 125 or so. Yet, a careful reading of hiswork reveals amazing powers of concentration andanalysis…powers of thought far in excess of those suggestedby a z score of well under two standard deviations above thepopulation mean. Could this be evidence that somethingmight be wrong with the way intelligence is tested? Could itmean that early crystallization of intelligence, orspecialization of intelligence in a specific set of (sub-g) factors– i.e., a narrow investment of g based on a lopsidedcombination of opportunity and proclivity - might put itbeyond the reach of g-loaded tests weak in those specificfactors, leading to deceptive results?Arthur Jensen: I don’t take anecdotal reports of the IQs of 1
  9. 9. famous persons at all seriously. They are often fictitious andare used to make a point - typically a put-down of IQ test andthe whole idea that individual differences in intelligence canbe ranked or measured. James Watson once claimed an IQ of115; the daughter of another very famous Nobelist claimedthat her father would absolutely “flunk” any IQ test. It’s allridiculous. Furthermore, the outstanding feature of anyfamous and accomplished person, especially a reputedgenius, such as Feynman, is never their level of g (or their IQ),but some special talent and some other traits (e.g., zeal,persistence). Outstanding achievement(s) depend on theseother qualities besides high intelligence. The special talents,such as mathematical, musical, artistic, literary, or any otherof the various “multiple intelligences” that have beenmentioned by Howard Gardner and others are more salient inthe achievements of geniuses than is their typically high levelof g. Most very high-IQ people, of course, are not recognizedas geniuses, because they haven’t any very outstandingcreative achievements to their credit. However, there is athreshold property of IQ, or g, below which few if anyindividuals are even able to develop high-level complex 2
  10. 10. talents or become known for socially significant intellectual orartistic achievements. This bare minimum threshold isprobably somewhere between about +1.5 sigma and +2 sigmafrom the population mean on highly g-loaded tests.Childhood IQs that are at least above this threshold can alsobe misleading. There are two famous scientific geniuses, bothNobelists in physics, whose childhood IQs are very wellauthenticated to have been in the mid-130s. They are onrecord and were tested by none other than Lewis Termanhimself, in his search for subjects in his well-known study ofgifted children with IQs of 140 or above on the Stanford-Binetintelligence test. Although these two boys were brought toTerman’s attention because they were mathematicalprodigies, they failed by a few IQ points to meet the one andonly criterion (IQ>139) for inclusion in Terman’s study.Although Terman was impressed by them, as a good scientisthe had to exclude them from his sample of high-IQ kids. Yetnone of the 1,500+ subjects in the study ever won a NobelPrize or has a biography in the Encyclopedia Britannica asthese two fellows did. Not only were they giftedmathematically, they had a combination of other traits 3
  11. 11. without which they probably would not have becomegenerally recognized as scientific and inventive geniuses. So-called intelligence tests, or IQ, are not intended to assess thesespecial abilities unrelated to IQ or any other traits involved inoutstanding achievement. It would be undesirable for IQ teststo attempt to do so, as it would be undesirable for a clinicalthermometer to measure not just temperature but somecombination of temperature, blood count, metabolic rate, etc.A good IQ test attempts to estimate the g factor, which isn’t amixture, but a distillate of the one factor (i.e., a unitary sourceof individual differences variance) that is common to allcognitive tests, however diverse. I have had personal encounters with three Nobelists inscience, including Feynman, who attended a lecture I gave atCal Tech and later discussed it with me. He, like the other twoNobelists I’ve known (Francis Crick and William Shockley),not only came across as extremely sharp, especially inmathematical reasoning, but they were also rather obsessiveabout making sure they thoroughly understood the topicunder immediate discussion. They at times transformed myverbal statements into graphical or mathematical forms and 4
  12. 12. relationships. Two of these men knew each other very welland often discussed problems with each other. Each thoughtthe other was very smart. I got a chance to test one of theseNobelists with Terman’s Concept Mastery Test, which wasdeveloped to test the Terman gifted group as adults, and heobtained an exceptionally high score even compared to theTerman group all with IQ>139 and a mean of 152. I have written an essay relevant to this whole question:“Giftedness and genius: Crucial differences.” In C. P.Benbow & D. Lubinski (Eds.) Intellectual Talent: Psychometricand Social Issues, pp. 393-411. Baltimore: Johns HopkinsUniversity Press. 5
  13. 13. Question #2Chris Langan: For practical purposes, psychologists define“intelligence” as problem-solving ability. But there are manykinds of problem, and some of them appear to involve factorsnot measured by standard IQ tests. For example, the“problem” of how to execute a complex series of dance stepsor athletic maneuvers clearly involves a cerebellar “factor”.Some experts would object that intelligence implies a level ofabstraction not required to solve kinesthetic “problems”. But ifproblems must be abstract in order to qualify for inclusion inintelligence tests, why the correlation of IQ with chronometricindices involving sensorimotor components and virtually noabstraction, e.g. simple reaction time?Arthur Jensen: This is the trouble with defining“intelligence.” If IQ tries to estimate g, it’s not going toestimate every particular ability, because g is a factor common 6
  14. 14. to all mental abilities. “Mental abilities” is a more useful termand the various mental abilities measured by all sorts of testscan classified hierarchically by means of factor analysis interms of their generality, that is, the amount of variance theyhave in common with other tests and other factors. The factorcalled g (for general) is at the top of the hierarchy onlybecause it is the one factor that all other mental abilities havein common (this is explained in detail in Chapters 3 and 4 ofmy book The g Factor). The g loading of a given test or of some lower-order factorin the factor hierarchy isn’t a measure of importance of thegiven ability but of its generality. Pitch discrimination is anability with a low g loading i.e., (it is correlated only about .30with), but it is a crucially important ability for a musician andis totally unimportant for a mathematician. The ability todiscriminate hues also has a g loading of about .30 and it isvery important for an artist, but not at all for a musician or amathematician. Various abilities differ markedly in g loading,but one of the interesting things about g that can’t be saidabout other ability factors, is that to succeed in almost anykind of intellectual pursuit, some minimum threshold level of 7
  15. 15. g ability is necessary, though it may not be sufficient. A highlevel of some special ability combined with very low gdescribes an idiot savant, but not a mathematician, musician,or artist in any socially important sense. For many types ofsubject matter and intellectual skills, achieving a high level offacility or mastery depends upon a fairly high g threshold.Abstract types of problems are usually included in IQ testsbecause they tend to be more highly g loaded than simpler orless abstract problems, and it is more efficient in terms of testlength to include high-g items in IQ tests that are intended toestimate an individual’s standing on g in some referencepopulation. However, it is possible to measure g withoutusing abstract test items or even anything that seems very“cognitive”. The inspection time (IT) paradigm is a goodexample. IT is the average the speed (visual or auditoryexposure time) with which a person can correctly make anexceedingly simple discrimination. This measure correlatesabout + .50 with IQ as measured by complex and abstract testitems. A combination of several such sensory-speed tests willrank-order people about the same as does the conventionalIQ. But these chronometric tests are less efficient for most 8
  16. 16. practical purposes, because they require individual testingwith special laboratory equipment and require a longertesting session. One can get essentially the same result with a15-minute paper-and-pencil test that can be administered to alarge number of people at the same time. Psychometrics hastwo main aspects: (1) theoretical and research-oriented, and(2) practical and applied. They are related, of course, but oftenlook very different and are usually engaged in by differentpersonnel. The key question is why are reaction times and simplesensory-motor types of performance correlated at all with IQderived from tests composed entirely of complex, abstractproblems. The simple answer is that such different types oftests are correlated because they all reflect g to some extent. Itis the next question to which we still have no good answer:What is this g? There are theories and hypotheses, but nonethat has proved entirely convincing, empirically proved, orgenerally accepted by experts in the field. It has to be someproperty (or properties) of the brain that enters into everykind of behavior that involves a conscious discrimination,choice, or decision. The main focus of present-day research on 9
  17. 17. intelligence is the discovery of the nature of this property ofthe brain that accounts for the empirical fact of g. It is alreadyknown that a number of different physically measured brainvariables are correlated with g; but how they work together tocause individual differences in abilities and theirintercorrelations is still mysterious. Several chapters of The gFactor are devoted to this subject. Another recent bookdevoted entirely to this question is excellent, but quitetechnical: Deary, I. J (2000). Looking down on humanintelligence: From psychometrics to the brain. OxfordUniversity Press. 10
  18. 18. Question #3Chris Langan: As already observed, intelligence is the abilityto solve problems. But while one psychologist talks aboutfluid g, a general intelligence factor that affects the solution ofany problem at all, another talks about multiple intelligencesapplying to different kinds of problem. To some extent, thedistinction between intelligence factors and multipleintelligences appears to be semantic; as you have observed, itis easy to overlook with regard to the kinds of problem foundon IQ tests, e.g. verbal problems, spatial problems andquantitative problems. So aside from the fact that themultiple-intelligences school effectively expands the meaningof intelligence by expanding the meaning of “problem” toinclude those encountered by (e.g.) athletes and dancers, what(if any) is the difference between the two approaches…which,as you point out in The g Factor (p. 128), rely equally on the“threshold nature” of g? In your conversations or 11
  19. 19. correspondences with Gardner, has he ever explicitlyrepudiated the mathematics of factor analysis?Arthur Jensen: It would be better to call “multipleintelligences” multiple factors. Some of the “multipleintelligences” named by Howard Gardner haven’t yet beenincluded along with a variety of other tests in any large-scalefactor analyses, so we don’t know if they would show up onalready establishes factors or would add new factors to theoverall map of the factor structure of human abilities. In anycase, several of Gardner’s “multiple intelligences” would atbest qualify as lower-order factors (most probably first-orderfactors) in the well establishes 3-stratum hierarchy of humanability factors (Carroll, J. B [1993] Human cognitive abilities: Asurvey of factor analytic studies. Cambridge UniversityPress). They are not measured by IQ tests (although they mayhave low correlations with IQ) because IQ tests are intendedto assess the g factor and therefore they include mainly testitems that best reflect g. There’s something to be said formeasuring g in as pure a form as possible and using othertests to measure various other factors as purely as possible, 12
  20. 20. although it turns out that no tests known, so far, exclude somedegree of correlation with g. The g factor, however can bemathematically “regressed out” of a measure of some otherfactor that one wishes to measure independently of g. Becausethe basic musical aptitudes (e.g., discrimination of pitch,duration of tones, timbres, and memory for rhythms) are allcorrelated with g, one may be interested in measuring theseindependently of an individual’s level of g. This would bedone, for example, in a study of the heritability of musicalaptitudes. Because g is highly heritable, the investigatorwould want to know if the musical aptitude variables areheritable independently of g and would use the statisticaltechniques of regression or partial correlation to answer thisquestion. As far as I know, Gardner doesn’t measure hisproposed “multiple intelligences” in any psychometricfashion, but I would bet that the development of any of themto a degree that would make for expert or professional levelsof performance requires an above-average threshold level ofg. The children who attended Yehudi Menuhin’s school formusically talented students and had been selected solely onthe basis of their demonstrated musical talent on some 13
  21. 21. musical instrument, for example, had an average IQ of 127.Does anyone want to bet that you could find a concertviolinist or pianist with a low IQ? The talent without the gingredient to go with it results at best in an idiot savant kindof performance, not a “musically intelligent” performance.The same goes for art, and most probably dance, althoughthat has not been tested, to my knowledge. I have taken part in two symposia with Howard Gardnerand have also had correspondence with him regarding g. Hisposition at that time (and also probably today) is thatalthough he believes in the existence of psychometric g, hesimply doesn’t think it is very interesting or important. I, andmany others, on the other hand, think that discovering thenature of g is one of the scientifically most interesting andimportant subjects in the quest to understand human nature.Others, such as Professor Linda Gottfredson are especiallyinterested in the “sociology of intelligence,” or the effects ofindividual and group differences on educational, social, andeconomic aspects of the human condition. I should add that I do enjoy reading Gardner’s books. Iespecially recommend Creating Minds (1993) as of special 14
  22. 22. interest to members of the Mega Foundation. This book alsoreinforces my view that eminence depends very much onother factors besides g. Gardner admits, however, that just onthe basis of IQ alone at least 90% of the general populationwould be excluded from the category of the creative geniuseshe writes about in his book. To then try to minimize theimportance of g and its critical threshold property is, I think, aserious mistake. That is my chief complaint with Gardner,along with his disregard for any form of quantitativetreatment of the variables he discusses but which is necessaryif his claims are to be objectively tested by himself or by otherresearchers. 15
  23. 23. Question #4Chris Langan: Given that intelligence is problem-solvingability, scant attention is paid to perhaps the most importantproblem of all: selecting a problem worthy of one’s time.Historically, the term “genius” has been associated withpeople who have solved this problem, and having solved it,went on to solve the very urgent, very complex problem(s)they had chosen. Indeed, many of our best minds considerthemselves too busy with important problems to bother withthe relatively trivial items in IQ tests. This suggests that amore realistic measure of genius might be obtained bystudying a brilliant subject in his or her “natural habitat”,analyzing the importance and computational complexity ofthe real-world problems that he or she has solved or failed tosolve (and with further research, perhaps even the intelligencefactors required). What do you think of this alternative? 16
  24. 24. Arthur Jensen: This is a very important point and it is mostimportant in the up bringing and development ofintellectually gifted children. I know of true prodigies -children with IQs in the 170-190 range - who were able tograduate from major universities, with majors in math andscience, when most children their age are in junior highschool, yet their early adult lives have been spent in trivial,but often quite lucrative, activities. It is interesting to note thatnot one of the four financially most successful adults who aschildren had been selected for Terman’s study of giftedchildren (IQs>139) ever went to college. The moral of thisstory seems to be that if you are really very bright and yourmain aim in life is to make loads of money, you should getstarted early and don’t waste your time going to college. But Isurely wouldn’t say that J. D. Rockefeller, Henry Ford, BillGates and their lives are not of great value to society. Theyare geniuses in their way, and they have made greatcontributions to the society. No one really knows why some children never acquire ordevelop the important kinds of values, ambitions, and goalsthat we consider laudable and most beneficial to society, 17
  25. 25. while others of comparable or even lesser intelligences maydo so. And those who do so in the extreme (e.g., Beethoven,Darwin, Gandhi, Einstein, and other stars of the lastmillennium) are an exceptionally rare minority among anycohorts with a comparable level of sheer cognitive ability. It is known that interests and values, as assessed byquestionnaires and inventories, have considerably highheritability, as shown by the high correlations betweenparents and their biological as compared with the lowercorrelations between adoptive parents and their adoptedchildren, and by comparing the correlations between fullsiblings with the correlations between unrelated childrenreared together. Most of us feel disappointed to seeindividuals with conspicuously high innate abilitiesaccompanied by a set of interest and values that scarcelycorrespond to what we would deem the best fulfillment of theindividual’s potential for achievement. The issue boils downto the question of to what degree interests and values can beinculcated in young people. It may well be that what wewould consider “greatness” is such a unique constellation ofabilities and traits that it would be virtually impossible to 18
  26. 26. inculcate all the necessary qualities of the particularconstellation in any given individual picked on the basis ofjust one of these qualities, such as a high IQ, or special abilitysuch as musical talent. This is an example of what behavioralgeneticists now refer to as emergenesis: the exceptionalachievement results from a particular constellation of traits(including interests and values), and does not emerge if anyone of them is lacking. Thus, for example, the differencebetween Richard Wagner and his son Siegfried Wagner (alsoa composer and conductor, though light-years from hisfather’s level of creativity) could have been Siegfried’s lack ofone or two traits in the rare constellation that permittedRichard Wagner to become recognized as one of the worldsgreat geniuses. It might well have been Richard Wagner’snotably high level of the trait “psychoticism,” which was notevident in his son’s relatively normal, low-key, mild-mannered, and modest character (see the reference in myanswer to Question #1 and my answer to Question #11). Thekind of study you propose is, in effect, the biographicalanalysis of persons of great accomplishment. There are anumber of such biographical studies in the literature. The 19
  27. 27. leading researcher on this topic is Professor Dean K. Simontonin his three fascinating books Scientific Genius, Greatness, andOrigins of Genius (also of interest: Genius, Creativity, andLeadership: Histriometric Inquiry - Editors). The subject istreated in a much more biographical and anecdotal, thoughvery insightful, way in Howard Gardner’s Creating Minds(1993). 20
  28. 28. Question #5Chris Langan: The study of neural networks suggests that assoon as we can explore the microscopic structure of thehuman brain and its sensory pathways, including neuralconnectivity and neurotransmitter concentrations, in vivo –e.g., through new medical scanning procedures – we canachieve what amounts to a purely biological measure ofintelligence. Do you think that such a measure will ever bewholly sufficient, or do you think that refinement byperformance-based tests will always be necessary?Arthur Jensen: I’m not at all sure about “intelligence,” whichis a poorly defined term, but the g factor, I believe, willeventually be explainable completely in terms of brainphysiology along the lines suggested in your question. Giventhe present technology and with a concerted effort this couldprobably be accomplished within the next two or three 21
  29. 29. decades. And it will be possible to measure g physically interms of brain variables. The practical measurement ofabilities, however, may remain at the psychometric level,because of its demonstrated practical validity and ease ofobtaining measures, as compared with MRI brain scans, PETscans, evoked potentials, laboratory tests of brain chemistry,etc. Performance-based tests will always be necessary forassessing learned skills and achievements (for which the rateand depth of acquisition will inevitably be related to g as wellas to motivational and personality variables andenvironmental circumstances). But much of what is nowunder the purview of psychometric assessment will be takenover by chronometric measurement, which will have morescientifically meaningful links to brain physiology than doconventional psychometric tests (see my answer to Question#31). 22
  30. 30. Question #6Chris Langan: Certain high-ceiling intelligence tests,generically called “power tests”, are composed of extremelydifficult items requiring higher levels of problem-solvingability than the items on ordinary IQ tests. Since these itemsusually have no known algorithms, their solutions cannot belooked up in a textbook, and where subjects do not know eachother, one must rely on intrinsic problem solving ability.However, by virtue of their difficulty, these problems takelonger to solve… sometimes days or even weeks. Accordingly,power tests are untimed and unsupervised. This opens thedoor to factors like motivation and persistence, which are notamong the factors primarily measured by standard IQ tests.On the other hand, virtually every significant intellectualachievement of mankind has involved these factors in greatmeasure. So why does the psychometric community still payno attention to power tests or the statistics derived fromthem? 23
  31. 31. Arthur Jensen: There are many power tests (i.e., non-speededor untimed tests) in psychometrics, although not of the kinddescribed in this question. Such tests would have littlepractical use, although they could be of scientific interest instudying the nature of high-level problem solving. But peopleeven capable of taking such tests could be identified withsome conventional tests, such as a combination of theAdvanced Raven Matrices and Terman’s Concept MasteryTest. People with high scores on such tests can demonstratetheir problem solving ability in their careers. What is the needfor prior selection? They can make it into college and graduateschool if they’ve got high IQs, and it will be their virtuallyunique constellation of traits (g + special abilities + motivation+ character, etc.) that will determine whether the will, first ofall, identify important problems, and secondly, be able tosolve them or at least materially contribute to their eventualsolution. Solving problems, or even thinking up problems, forwhich there are presently no algorithms, takes us into therealm of the nature of creativity. There are as yet nopsychometric tests for creativity in a nontrivial sense. We can’t(yet) predict creativity or measure it as an individual trait, but 24
  32. 32. can only examine its products after the fact. At present, thereare much more tractable problems for research in the realm ofhuman abilities, the most important of which, I believe, isdiscovering the physical basis of g. 25
  33. 33. Question #7Chris Langan: In science, theories and the definitionscomprising them are required to have models, and thesemodels are required to fit into an overall model of reality. Forexample, in physics, the predicate “velocity” must besemantically connected to real physical objects in relativemotion, which must in turn be embedded in a model of spaceand time supporting a mathematical definition of “motion”(e.g. the analytic geometry of classical mechanics). But thisbecomes problematic with respect to psychological predicateswith subjective components for which we lack objectivemodels, e.g. consciousness, qualia and emotions. Intelligence,which is studied strictly in terms of its effectual correlates, isto some extent such a predicate. Can we achieve a trueunderstanding of intelligence without a model of realitytranscending the absolute separation of mind and bodyassociated with Cartesian dualism? 26
  34. 34. Arthur Jensen: This is a profound question and gets right atthe heart of many of the problems of psychology and makingit truly a natural science. Of the important variables inpsychology, “intelligence” is one of the few that may lenditself to being researched strictly as a natural science. Much ofpresent-day psychology is, at best, a kind of appliedtechnology, some of it highly useful. But even more ofpsychology is a kind of shamanism, which will always be herein one form or another, with a relationship to science muchlike that of alchemy and astrology. Unfortunately this pseudo-scientific kind of psychology, is the only side of psychologyknown to the general public, and it is something of anembarrassment to those who are striving to advancepsychology as a natural science. A Serious part of the problem is the importance ofmeasurement in the sense of measuring the behavioralphenomena of interest by means of true physical scales, i.e., aratio scale that is standardized to be invariant across earthlytime and space, so that something measured in, say, Bombayin the year 2001 can be directly compared with something 27
  35. 35. measured in New York in the year 2050, just as we can saythat the average height of 18-year old male U.S. Army recruitsin 1916 was, say, 5’9” and in 2000 was 5’10”. There are almostno psychological variables that can be measured on such atrue scale on which values can be expressed as ratios or onwhich nominally equal differences between pairs of values indifferent ranges of the scale can be treated as truly equalintervals. The mathematical and statistical treatment of datawithout these true scale properties is thereby seriouslyhandicapped. The most natural scale of true measurement forsome psychological variables, e.g. mental abilities, is in unitsof time. It is now well established that certain kinds of timedperformance, measured in seconds or milliseconds, arecorrelated with scores on psychometric tests, which are thebest ordinal (i.e., rank-order) scales of performance. I believefurther developments in the use of time-measuredpsychological variables, such as various reaction time andinspection time paradigms (see Chapter 8 in The g Factor),can help to advance truly scientific research on individualdifferences in mental abilities. (See my answer to Question#31.) Of course, psychology as a natural science can have no 28
  36. 36. use for mind-body dualism. I think I was born opposed tothat notion. 29
  37. 37. Question #8Chris Langan: As academic performance falls, there is agrowing tendency among educational theorists to claim thatthere is no such thing as a bad student, only bad teachers(common sense, of course, says that there are both). Learningtheory, currently the vogue among educators, distinguishesthe different “learning styles” of students and offers variousprescriptions for helping students perform up to capacity. Iwas recently told by several graduating teachers that (1) IQ israpidly becoming a forbidden topic in educational curricula,and (2) the current vogue is a combination of “brain-basedlearning” (inspired by the Multiple Intelligences model) and“cooperative learning”, in which students with different“learning styles” (e.g. graphic, visual, auditory or kinesthetic)contribute to each other’s learning process. What is your takeon these strains of learning theory? Do they constitute a validapproach to the problem of declining scholastic achievement? 30
  38. 38. Arthur Jensen: The purported decline in academicperformance in schools and colleges is a terribly complexphenomenon to get a handle on for serious discussion. Itundoubtedly has many causes, mainly associated with thevery concept of universal education and the difficulttransition from different kinds and levels of education fordifferent segments of society and an increasing uniformity ofeducation for the entire population. Individual differences inabilities are largely ignored by the educational system and theconspicuously continuing effects of their presence in theeducational process therefore has given rise to forms of denialthat blames teachers, curricula, and institutions. It has alsogiven currency to theories that deny or minimize the reality ofindividual differences or attributes their causes to supposedfaults of the schools and of society in general. The now knownscientific facts about individual differences (and I emphasizethe word “individual” here) have to be faced and dealt within the design of education. (Group differences basically aresimply aggregated individual differences.) In general, a muchmore highly diversified educational system is called for. It isstill too early to give up trying different approaches to 31
  39. 39. discover just how the required diversity can be accomplished.But each of the proposed approaches must be clearlydescribed and its results assessed in the nature of a trueexperiment. Educational practices tend to be a parade of fadsand we see new ones come around every year to replace lastyear’s. Few if any of these trial balloons face the real problemsconfronting public education. In the whole scene, I believe theindividual classroom teachers are the least deserving ofblame. 32
  40. 40. Question #9Chris Langan: The founders of Mensa, regarded by many asthe original high IQ club, complained that the group hadforsaken its original purpose…that instead of pooling itsintellectual talent to solve the most urgent problems ofsociety, it had fallen into aimless socializing and dilettantism.Since then, a small number of more rarified groups, knowncollectively as the UltraHIQ Community, have advocated areturn to the original vision. What is your opinion regardingthe concept of a pool of intellectual talent based strictly onhigh levels of g and dedicated to finding solutions for some ofsociety’s more urgent problems?Arthur Jensen: It’s hard to imagine how a group of high-IQpeople with little else in common besides their IQ andprobably differing in many other ways perhaps even morethan a random sample of the population can do much to effect 33
  41. 41. social change or carry out a large project with a unified aim.On the other hand, a group of persons with a wide range ofIQs from average to very high who have come together as agroup because they all have a similar philosophy and somerealistic goal based on it could be a force for some concertedkind of achievement. If there were a subgroup of UltraHIQindividuals all with a similar vision, aim, and dedication toachieve their common purpose, that would be something! But I wouldn’t apologize in the least for any High-IQsociety that was intended as a purely social organization thatqualified people could join simply because the find eachothers’ company more congenial than that of most of thepeople they would be apt to meet in other social groups. Isuspect that the “zone of tolerance” for the intelligence levelsof one’s friends and spouses is probably, at the outside, aboutone’s own IQ +/- 20. People in the upper-half of the IQdistribution are more closely assortative in this respect thanare those in the lower half. In the general population, spousesimilarity in IQ is about the same as full-sibling similarity.Assortative mating for a given trait has the effect of increasingthe genetic variance in that trait in the offspring generation. It 34
  42. 42. is estimated that some 15 to 20 percent of the populationvariance in IQ is attributable to the effect of assortativemating. 35
  43. 43. Question #10Chris Langan: Intelligence is about solving problems.Because problems consist of constraints to be satisfied by theirsolutions, those with high IQs are good at working within thebounds of more or less complex constraints. Yet someproblems, especially those involving “lateral thinking”,require creativity…the ability to break free of apparentconstraints. So to some extent, attributes like creativity,novelty and originality seem paradoxically related tointelligence. Have we had any success in relating creativity toIQ, and specifically to g?Arthur Jensen: About all I can say on this is that the level of gacts as threshold for the possibility of creativity and that thisthreshold differs somewhat for different fields of creativity,particularly to the extent that the field calls for a special talentthat somewhat outweighs the relative importance of g. The 36
  44. 44. main reason that a fairly high level of g acts as a threshold isthat to be creative in most fields, one has to master the basicknowledge, techniques, and skills needed just to be able towork in the field, to say nothing of being creative in it. Thecognitive demands on achieving the essential level of masteryof the working tools are typically considerable and are oftenhighly g-loaded. Hence you don’t find truly creativescientists, writers, musicians, etc., with low or even averageIQs. A music composer, for example, must master suchabstract and complex subjects as harmony, counterpoint,orchestrations, and so on -- all g-loaded subjects. Plus anincredible amount of assiduous practice, so that much of thisknowledge and skill repertoire becomes automatized, therebyfreeing the individual for creative expression. Read thebiographies of any of the importantly creative people inhistory and you’ll find that the prerequisites and necessarypersonal conditions for creativity are above-average g plus anunusual capacity for work and persistence in the face ofdifficulty or adversity. 37
  45. 45. Question #11Chris Langan: Many people believe that genius and insanityare closely related. Indeed, history provides numerousexamples of creativity and insanity or (near-insanity) in closeconjunction. Statistically, does intelligence correlate eitherpositively or negatively with any kind of insanity or mentalinstability?Arthur Jensen: The supposed relationship between creativityand mental disorder has been well researched and is provento be a fact. Depression and bipolar disorder have a higherincidence among creative writers and artists than in thegeneral population; schizothymic characteristics aresomewhat more frequent among philosophers,mathematicians, and scientists. The late Professor Hans J.Eysenck hypothesized a trait he called “psychoticism” whichhe thought was an essential ingredient in major-league 38
  46. 46. creativity. Psychoticism is not itself a psychiatric disorder ordisabling condition (although it is associated with a pronenessfor such), but a constellation of intercorrelated personalitytraits, most of which I have found in virtually every famouscreative genius I’ve read about. Eysenck’s theory and theevidence for it is the most interesting I have come across inthis field. This is a complex subject and I couldn’t possibly doit justice by trying to explain it all here, but I will recommendthe following two books, which are the best I’ve come acrosson this topic: H. J. Eysenck, Genius: The Natural History of Creativity.1995, Cambridge University Press. M.A. Runco & R. Richards (Eds.), Eminent Creativity,Everyday Creativity, and Health. 1998, Ablex. 39
  47. 47. Question #12Chris Langan: Even IQ tests with moderate ceilings can beupwardly extrapolated, and there exist experimental high-ceiling tests that appear to have much higher ranges thanstandard IQ tests when anchor-normed on those samestandard tests. Indeed, whatever the limitations on itsmeasurement, there would seem to be no a priori ceiling onintelligence itself. Yet, some claim that the very idea of an IQin excess of +4σ is “meaningless”. In your opinion, can it befruitful to consider IQs in excess of +4σ? What, if any, is theabsolute upper limit on the measurement of IQ?Arthur Jensen: I believe we have no means at present ofdetermining a ceiling for intelligence or for extrapolatingexisting scales to a theoretically derived ceiling. I’m not evensure if the idea of a ceiling for intelligence is a meaningfulconcept. An upper limit for the measurement of g may be 40
  48. 48. more meaningful and +4σ (IQ of 160) may well be the highestlevel in which we can have much confidence that it is g that isbeing measured. It has long been known that various testsbecome less g loaded the higher one goes in the IQdistribution. That is, if we gave a large battery of diverse teststo people with IQs above, say, 120 (i.e., the top 10% of thepopulation) and to people with IQs below IQ 80 (the bottom10%), we will find that the correlations among the tests areconsiderably smaller in the high IQ group than in the low IQgroups, and consequently the tests have less in common (i.e.,their general factor g) and hence lower g loadings in the highthan in the low group. This appears to be quite a linear effectas we move up the IQ scale. If the IQ scale were a true intervalscale (we only assume it to be such), we could extrapolate thelinear trend to the point at which g loadings = 0. That, then,would be the ceiling of the g factor. High IQ persons’ abilitiesbecome more highly differentiated and specialized, hence areless correlated with one another and afford a weaker basis ofprediction of any particular ability from a knowledge of theindividual’s standing on some other ability. Yet this diverse ordifferential development of mental abilities itself seems 41
  49. 49. dependent on the possession of a fairly high level of g, in thesense of superior performance on the kinds of tests that arethe most g loaded. The problem in researching the uppermost region ofhuman abilities is that the further we go above the mean IQ,the smaller is the proportion of the population that we canobtain as research subjects, and, since research in this fielddepends a lot on statistical inference, we would find itexceedingly difficult, or even impossible, to obtain largeenough subject samples to permit statistically significantconclusions. The more highly selected the subject sample, thesmaller is the variance of the test scores and their reliability.There are more tractable and scientifically more importantthings to be researched at present. Because there is little if anypractical value in measuring ability levels above the 99thpercentile in the general population, hardly anyone, least ofall the producers of mental tests, is interested in doing so. Theonly interest I have ever seen has been among some membersof the high IQ clubs that are offshoots of Mensa. I once testeda group of some 20 to 30 volunteers from Mensa. On astandard psychometric test they averaged about 20 IQ points 42
  50. 50. or so above the average of U. C., Berkeley, undergraduates. Iwas interested in whether the Mensa subjects would alsoshow faster reaction time (RT) than Berkeley undergrads, whoon our RT averaged about +1 s above the general populationmean on such tests. The Mensa subjects averagedconsiderably faster RT than the Berkeley students. The factthat RT is monotonically related to IQ throughout an 80-points IQ range, from about IQ 60 to at least IQ 140, suggeststhat it might be a useful tool in studying the upper reaches ofability, strange as that may seem. But of course there is aphysiological limit to RT, determined in part by the limits ontime for sensory transduction of the stimulus and afferent andefferent nerve conductive velocity. But RT has the advantagesof measurement on a ratio scale and also of being based onthe very same test at all levels of IQ (beginning at a mentalage of about 3 years, below which subjects typically havedifficulty in performing the RT tasks without training). 43
  51. 51. Question #13Chris Langan: Intelligence is the ability to reason, i.e. to solveproblems. Problems are solved according to proceduralschemata called algorithms. Algorithms can be learned. Ergo,intelligence can to some extent be learned. Equivalently, amathematician specializing in neural networks might say thatsince the intelligence which becomes “crystallized” insynaptic weighting patterns is algorithmic in both form andcontent, neural nets can be trained for “intelligence”. Thebrains of children undergo structural development, and evenadult brains retain a certain amount of neural plasticity. Soeven though statistics indicate that IQ tends to be stablethroughout the human lifespan, does it remain possible thatunder the proper conditions, IQ can to some extent belearned…that a general set of high-level algorithms can beburned into cerebral synapses? Would such an IQ boostnecessarily be “hollow” with respect to g? 44
  52. 52. Arthur Jensen: Yes, certainly. Various thinking or problem-solving algorithms can be trained and even automatizedthrough extensive practice. These phenomena are associatedwith neural plasticity and the innate capacity for learning. It isindividual differences in these brain attributes, rather than theacquisition of specific algorithms for thinking and problem-solving per se, that are the basis of the g factor. Algorithmictraining is remarkably specific to a particular subject-matterand has surprisingly little transfer beyond the material onwhich it has been trained. This is one of the problems withmost conventional IQ tests, verbal and nonverbal tests alike:two things are being measured: g + learned algorithmicthinking and problem-solving skills, and these are completelyconfounded in the total score on the test. Chapter 10 in The gFactor deals with just this problem, which is described as theconfounding of the vehicle (e.g., the knowledge and skilldemands of a particular test) for measuring a given constructand the construct itself (e.g., the g factor). This is a bigproblem, often insufficiently recognized by the users mentalability tests. It is much less a problem in explicit achievement 45
  53. 53. tests. A test in algebra, for example, may be a poor way ofassessing g, but a good way to find out where a person standsin knowledge and use of algebra. If everyone tested had takenequivalent courses in algebra, the scores on the algebra testwould also be quite highly g-loaded (i.e., correlated with g).For persons who have completed high school, tests of readingcomprehension measure g about as well as most IQ tests,except for true dyslexics. One of the potential advantages ofchronometric tests (e.g., reaction time and inspection time) isthat they have some g loading yet have virtually nointellectual or algorithmic content. Their disadvantage is thatthey also measure, besides g, a large component of purelysensory-motor abilities that fall entirely outside the domain ofmental abilities (as shown by their lack of correlation with anyother kinds of cognitive tests). The learning of problem-solving and other algorithms iscrucial in most realms of intellectual work and it can beinculcated to a considerable degree through training. It mayeven improve certain test scores to some extent. But this is notthe same as improving whatever it is that makes for g. In fact,the level of algorithmic complexity that can be acquired is 46
  54. 54. limited by an individual’s level of g. Before children areexposed to any kind of maths, for example, one can makefairly good predictions on the basis if IQ of which ones will orwill not top out in various levels of higher abstractmathematics, regardless of educational opportunity, effort,and the like. Only persons in the top 15% of the IQdistribution are employed as mathematicians; that seem to bethe absolute minimum threshold for this occupation. Manystudents entering college whose ambitions are to be rocketscientists or engineers soon discover they can’t make the mathrequirements despite their most earnest efforts to do so. 47
  55. 55. Question #14Chris Langan: In The g Factor, you state (regarding the FlynnEffect) that “Whatever causes the rise in IQ, it has its greatesteffect on those at the lower end of the scale, with acorresponding shrinkage of the standard deviation.”However, since it is unclear how adult IQ scores above 100were normed on older IQ tests that relied on mental age, it isunclear whether the distribution to which you refer is thatcharacterizing ratio IQ or deviation IQ, where ratio IQ isthought by some theorists to be lognormally rather thannormally distributed (e.g. Vernon Sare, University of London,1951). Can you clarify this point?Arthur Jensen: The Mental Age/Chronological Age, or100(MA/CA) = IQ, has been virtually defunct since the 1940’s.All professionally constructed and published IQ tests todayare based on deviation IQ [i.e., z = (Raw Score - Mean )/SD, 48
  56. 56. and IQ = 15z + 100]. The ratio IQ becomes increasingly suspectas children get older. It is based on the presumed (ordemonstrated) linear relationship of the test’s raw scores toCA. But this relationship begins to depart from linear ataround 12 to 13 years of age, and after age 15 (it used to be 16)it is so nonlinear that the MA/CA ratio becomes increasinglymeaningless with increasing age. Often the raw scores on atest are converted to normalized z scores and then convertedto IQs, ensuring that the IQs are normally distributed; at leastin the standardization sample. If we assume that intelligenceshould be normally distributed, and if the IQ distribution ismade perfectly normal (i.e., Gaussian), then we can claim thatIQ is an interval scale. But the assumptions are the criticaljoker in this line of reasoning. There is nothing that actuallycompels these assumptions; they are merely plausible andstatistically convenient. The best single study of the Flynn Effect (i.e., the secularrise in IQ over the past several decades) was done in Denmarkwith military conscripts. The lower portion of the IQdistribution showed larger gains than the higher end,probably because in the more recent decades more of the 49
  57. 57. lower portion under the bell curve received more educationalattention and better education, and also probably better pre-and post-natal health care and nutrition. As raw scores on mental tests are based simply onnumber of correct answers (a function of item difficulty, i.e.,percent of population passing an item), which constitutes onlyan ordinal (rank-order) scale of ability on the given test, anytransformation of the scale -- normal, lognormal,hypergeometric, or whatever -- really has the same status asan ordinal scale, i.e., the raw scores or any transformation ofthem could just as well be treated as ranks. These can beconverted to percentile ranks, a given percentile simplyindicating the percent of persons in the standardization groupthat fall below a given raw score (number right). Thesepercentiles can also be transformed to normalized orlognormalized scores (or any other transformation) if onewants to make assumptions about the form of the distributionof the latent trait (e.g. intelligence) in the population; but notan iota more of real information in conveyed by thesetransformed scores than is present in the ranked scores. Nowif our measure were true physical measures (i.e., a ratio scale) 50
  58. 58. but were expressed as ranks, their rank order would coveyless information than the raw scores themselves. A true ratioscale (e.g., height, weight, reaction time) is a necessary andsufficient condition for describing the form of theirdistribution in a given population or random sample of somespecified population. That’s why the “Flynn Effect” for theincrease in the average height in the population has notcreated any controversy as it has in the case of IQ. By having aratio scale, the phenomenon and its magnitude are clearlyestablished by the raw measurements, whatever may be theircause. But no one argues, “Is it really height that hasincreased?” That is the whole argument about the Flynn Effectand IQ -- is it really intelligence that has increased, or only testscores? When we get true ratio scales of mental abilities, wewill be able to answer the kind of question you are asking.The scientific study of developmental trends in mentalgrowth is greatly handicapped by our lack of true ratio scales,without which the shape of the growth curve of mental testscores is almost meaningless beyond saying it is positivelymonotonic between any two points on the scale ofchronological ages, up to about age 20. 51
  59. 59. Question #15Chris Langan: Why are IQs measured on relative scalesrather than in absolute terms? Saying that someone is brighterthan than 99% of the population is no more meaningful thansaying that someone is taller than 99% of the population.While raw scores on tests containing items of low to moderatecomplexity provide an “absolute measure” of sorts, they seemonly indirectly related to intellectual speed and power. Thesolution times of various problems, or the most complexproblems solvable without time constraints, would be moredirect measures of speed and power and thus more acceptableas absolute metrics. Are there other absolute measures ofintelligence, and if so, how do they relate to IQ?Arthur Jensen: This is a continuation of the previousquestion. I think it quite informative to know a personspercentile score (assuming it as accurate), as it tells you where 52
  60. 60. that person stands with reference to some "normative" groupon the trait in question. A pediatrician can rather preciselymeasure an infants head circumference with a tape measure(a ratio scale), but to interpret this measurement he needs tolook it up in a table of norms giving the percentile equivalentof that measurement (and its standard deviation) for theaverage infant of the same age. The only absolute measures ofintelligence I know of that are behavioral are various forms ofreaction time (RT) and inspection time (IT) measures, whichwe know, are related to IQ because of their significantcorrelations with IQ. Interestingly, the longer the average RTfor a task beyond about 1 second (for young adults), the less itcorrelates with IQ. In more complex tasks that take muchmore than 1 second to perform, other, noncognitive factorsenter in and "dilute" the RT measure with sources of variancethat do not represent whatever we mean by generalintelligence. Physiological measurements, which are a truescale, such as latency and amplitude of the evoked brainpotentials and rate of glucose uptake by the brain whilesolving a problem (measure by PET scan), and (in one study)the brains pH level, are all correlated not just with IQ, but 53
  61. 61. with the g factor per se. A combination of such chronometricand physical variables will one day yield ratio-scale measuresof mental ability that are scientifically more meaningful thanthose obtained from conventional IQ tests. The details of thistopic form, in part, my answer to Question #31. 54
  62. 62. Question #16Chris Langan: On most IQ tests, ceiling effects begin to occurabove the two-sigma level. Thus, ceiling effects can occurbefore deviations from a Gaussian distribution becomesignificant, effectively obscuring the deviations. But for (e.g.)blacks, the ceilings are high enough (in standard deviations)that significant differences ought to be apparent andmeasurable. E.g., if the SD for blacks were 12.75 (85/100 X 15),the 5 SD level would come at IQ 149 and the 4.75 SD level(one in a million) would be IQ 145.56. So blacks should beideal for studying the differences between ratio IQs and adultdeviation IQs, which seem to approximate lognormal andnormal distributions respectively. However, this raises somequestions: is the black IQ distribution normal, lognormal orPearson Type IV, i.e. "abnormal"? How has the Flynn Effectacted upon the black IQ distribution (where insulated fromthe heterotic effects of miscegenation)? 55
  63. 63. Arthur Jensen: This is a clever thought, although it hasbecome increasingly difficult to get IQ data on blacks, at leastin sufficient numbers to study the top-level percentile in theblack population. In light of what I said in my answersregarding scales and distributions, I dont think it would befruitful to pursue this issue with conventional tests. I havelooked at a great many distributions of both white and blackIQs in whole school populations. The black distributionsgenerally resemble the Pearson Type IV Distribution; it isconsiderably skewed to the right. Not as much, if any,theoretical significance can be attached to this observation aswould be possible if the mental measurements were a ratioscale. 56
  64. 64. Question #17Chris Langan: It has been argued that the deviations from anormal curve that occur among child IQs are simply afunction of varying rates of mental maturation. Thus, whilethe distribution of childhood ratio IQs looks closer tolognormal than normal, and while the distribution of someadult indices like AGCT-derived IQ scores shows a frequencypattern agreeing closely with childhood ratio-IQ distributions,the distribution of adult IQs is Gaussian. Now, if specificindividuals tend to regress toward the mean as they maturebut the overall distribution remains the same as it is forchildren, then there must be "late bloomers" who rise to taketheir places in order to keep the upper ranges of thedistribution populated. Has this phenomenon been studied?Do very high adult ratio IQs appear with greater-than-Gaussian frequency as they do with children, or are thedistributions different? 57
  65. 65. Arthur Jensen: Yes, the variation in IQ (or relative standing insome normative group) as individuals grow up from aboutage 2 (when IQs are first reliably measured) to maturity hasbeen studied quite thoroughly. (The subject is treated atlength in my book Bias in Mental Testing, Chapter 7, 1980Free Press). (Also see The g Factor, pp. 316-318.) IndividualsIQs fluctuate rather randomly up and down throughout theirdevelopment, but become increasingly stable with eachsuccessive year. This has been studied by looking at thematrix of correlations betweeen IQs measured every yearfrom age 2 to age 18 or so. The correlations are increasinglyhigher as a function of age. Many early bloomers and latebloomers exchange their positions in the IQ distribution, andin about equal numbers. Hence the overall distribution of IQsremains fairly constant throughout the entire developmentalperiod. 58
  66. 66. Question #18Chris Langan: It seems that research on the profoundly giftedhas not only been very limited, but that virtually none of itaddresses the question of how society can bring out the bestin its brightest members. One of our members, Bob Seitz, asks:"During my years with NASA and Georgia Tech, I casuallywondered why there didnt seem to be a national registry ofthe very brightest, with attention to their needs and theirencouragement. But when, two years ago, I finallydiscovered the ragged state of affairs vis-a-vis our brightest, Iwas shocked. It seems that as IQs rise from 75 to 125, dramatic changesoccur in life outcomes and socioeconomic statuses. But onceintelligence exceeds the upper part of that range, there seemsto be little correlation between IQ and success in even themost demanding intellectual pursuits. This raises thepossibility that high-IQ types are being neither allowed to 59
  67. 67. fully utilize their potential nor rewarded in proportion to theirabilities. One might expect this to detract from theirenthusiasm and level of performance. But even though thecosts to society may be immeasurable, no one seems to beaddressing or investigating the situation. Do you have anyopinions on this matter?"Arthur Jensen: This all goes back again to the fact thatachievement in a multiplicative (not additive) function of anumber of critical traits, of which g is only one, though a veryimportant one. Given a range of IQs sufficient for everyonewithin that range to be able to learn the "tools of the trade",then other personal factors become more critical determinantsof achievement. The more unusual the achievement, thegreater the number of different factors that have actedmultiplicatively to produce it. People do not tend toundervalue intelligence so much as they undervalue the othermultiplicative traits that enter into achievement. Ourexpectations for achievement are weighted too much for theneffect of IQ and not enough for other valuable traits. Becauseof its threshold nature, however, a low IQ is a handicap, and 60
  68. 68. even more so in our modern technological society than in themore agrarian past. Higher IQ is always an advantage in themultiplicative combination of factors required for outstandingachievement. One of the things most lacking in education, andoften also in parental upbringing today, is inculcation of thekind of values, including self-discipline, that are among of theessential ingredients in the multiplicative formula involved inoutstanding achievement. 61
  69. 69. Question #19Chris Langan: Aside from social ineptitude, perhaps the traitmost often associated with IQ > +4σ is being amultimillionaire (Bill Gates is a frequently-cited example). Itseems that when the hyper-gifted turn their hands to makingmoney, they succeed in spades. But with respect to socialutility, this is often a waste. We need cures for cancer…betterways to relate to each other…cures for Alzheimers andParkinsons Diseases…a marriage between general relativityand quantum mechanics. In short, we need real works ofgenius. But even though society has a vested interest in fullyutilizing the talents of its geniuses, it continues to let itself bevastly outbid for their services. We encourage “real geniuses”to squander their potential on what often turns out to bepointless, inflationary acceleration of the financial treadmillwhile discouraging those without academic credentials fromparticipating in the social and intellectual mainstream, relying 62
  70. 70. on the survivors of academic bureaucracy to solve our mosturgent problems. Unfortunately, academic politics is not avalid test of intelligence. Is there any effort to understandwhats going wrong in this area?Arthur Jensen: I believe that, generally, multi-billionaires dohave plenty of "social utility" --the Rockefeller, Ford,Carnegie, Sloane-Kettering, and Mellon foundations, forexample, not to mention the industries, jobs, and theirproducts that have benefited the whole society are indeed aboon to the whole society. These foundations built on thefortunes of these billionaires are responsible for many of thegrants made to researchers working on Alzheimers,Parkinsons, caners, AIDS, and a great many other medicaland humanitarian enterprises. The industrial and financialachievements on the scale of Gates, Rockefeller, Ford, Etc., itseems to me, are highly worthy of our admiration. I do agree that in todays world, especially in the UnitedStates, the job market places too much emphasis on academiccredentials, and not enough on the assessment of actualabilities. If I had to choose between knowing a job applicants 63
  71. 71. IQ or level of education, Id pick the IQ, assuming the jobdoesnt require some specialized skills that can only beacquired in college or graduate school. In todays world,however, one has to wonder about a high IQ individual whohas not finished high school or gone to college; one wouldwant to know about other achievements as well as theirpersonality traits. In personnel selection it is most valuable tohave objective test scores both on g and on subjects mostrelevant to the job as well as formal educational credentials.They are usually in fair agreement, but when not, they bearfurther looking into. 64
  72. 72. Question #20Chris Langan: In working with some of the profoundlygifted, Ive encountered a few hints about how theirextraordinary potentialities become derailed. There seem tobe major problems with the extremely gifted in a society thatisnt geared to them, like the plight of an eight-footer in ahouse with six-foot ceilings. How much attention has beengiven to the social and emotional problems of the highlygifted population?Arthur Jensen: I know other psychologists who are better ableto answer this than I can, for example Professors JulianStanley (John Hopkins), David Lubinski, and Camilla Benbow(Vanderbilt). It is true that most super-gifted children,especially as they approach adolescence, are not as challengedor as happy about going to school with their age-mates asthey would be if they were entered into a regular 4-year 65
  73. 73. college with classmates who are six or seven years older. Thechanneling that takes place in college and thereafter in theworld of work is such that people generally find themselvesin the company of others who are not all that different fromthemselves in abilities, interests, and the like. The super-ability types usually come to realize that people differ greatlyin abilities, and that they have to learn to live with this factgracefully. Those who dont learn this lesson pay a price. Ihavent yet seen a good case made for the idea that peoplebecome maladjusted simply because of their having a veryhigh IQ. Although IQ and mental health have only a slightpositive correlation with each other, its not in the leastsurprising to come across high IQ persons with emotional andinter-personal problems. But I doubt that any disability can beblamed on a persons having a high IQ per se. I do feel sorry for those children whose parents have beentold that their child is gifted and never let their child forget itfor one minute. (The singled-out childs siblings suffer as wellin this case.) Its interesting to read the later volumes ofTermans Genetic Studies of Genius (based on subjectsselected as school-age children with Stanford-Binet IQ>139). A 66
  74. 74. large majority of these "Termanites" became fairly ordinaryadults and some were less successful in life than are manypersons of average IQ. I have heard some educators expressconcern that something must have gone terribly wrong in theupbringing or education of many of the Terman group tocause the average level of their apparent achievements asadults to be so considerably less impressive than their IQ. Butthis IQ-achievement discrepancy is exactly what one shouldexpect in terms of the multiplicative theory of achievement Ihave described in my answers to some of the previousquestions. 67
  75. 75. Question #21Chris Langan: As students, doctors and lawyers take tests likethe LSAT, their average IQs are found to be around 127, whilein contrast, mathematicians average around 140. Has anyresearch been done relating test scores to minimallyacceptable professional performance in (e.g.) medicine andlaw, as gauged by (e.g.) deaths attributable to diagnosticerror, cases lost, or judgments overturned? Since certainstudies have found that IQ is a better predictor of jobperformance than educational credentials, shouldn’t we (andour licensing bureaus) be paying more attention to it? Is ourfailure to do so attributable to affirmative action or otherminority preference programs?Arthur Jensen: Excellent question. Probably the answer to itmight be too politically incorrect for anyone to be able to riskthe research that could answer it, or to even obtain a grant to 68
  76. 76. do such research. There are plenty of anecdotes that one hearsof, but I havent come across any bona fide research studiesthat investigated the relationship between test scores andperformance catastrophes at a professional level such as youmention. But it is hard to imagine that such a relationshipdoes not exist, since such a relationship has been amplydemonstrated by research on personnel selection in hundredsof jobs in which test validity has been determined in terms ofactual job performance. The U.S. Employment Service, usingthe General Aptitude Test Battery (GATB), has published theresults of literally hundreds of such test validation studies forpredicting success or failure in various job categories, notincluding doctors or lawyers or other high-level professionals.And it is the g factor of the GATB that carries most of thepredictive power of this battery composed of eleven diversetests. It would be a safe bet that doctors (or otherprofessionals) who are fired because their performance is at asub threshold level of competence have a lower average IQthan the competent majority of their profession. I intend tocirculate this question among some colleagues who are moreexpert on this topic than I and will let you know if there are 69
  77. 77. any studies that can provide a more definite answer to yourquestion. But the issue is so contaminated by the need forpolitical correctness that it may be virtually impossible toobtain a valid answer in the present climate. 70
  78. 78. Question #22Chris Langan: The “generality” of g reflects the fact that g isfound in conjunction with every other intelligencefactor…that, as you posit in The g Factor, it represents acombination of all of the distributive criteria that contribute tointellectual processing everywhere in the brain. Some of thesecriteria clearly have a genetic basis, e.g. neural and synapticdensity, neural conduction velocity, neurotransmitterabundances and control mechanisms, glial density, degree ofaxon myelinization and so on. Just as genetics dictates that arat is more intelligent than an insect and a man is moreintelligent than a rat, human beings differ in geneticconstitution and may therefore differ in these criteria. So g isbiologically plausible as well as empirically confirmed. Butwith the advent of the politically correct Multiple Intelligencestheory, it has fallen into disrepute among educators and beenrendered prematurely obsolescent. What is your opinion of 71
  79. 79. those who, being more enamored of political correctness thancommon sense, deny the existence of g despite its scientificbasis? Do you see a light at the end of the tunnel?Arthur Jensen: My answer to this question must already beobvious. The "light at the end of the tunnel" is simplyobjective empirical science. Those who would belittle the roleof g in human cognition could prove their case simply byshowing that their tests, or measures, or assessments of"multiple intelligences" are more highly correlated with anyimportant "real-life" criteria independently of g than thosecriteria are correlated with g alone. But most researchers of"multiple intelligences" dont actually measure anything at all.Their claims are based on purely literary, armchairpsychology. So there is no means of putting their theories toan empirical test. It is simply non-science and just a part of thepassing parade of untested notions that so frequently attracteducators and dilettantes. That some of these fads are alsoperceived as PC, of course, adds to their popular attraction. 72
  80. 80. Question #23Chris Langan: With each passing year, it seems that popularculture places a lower value on high intelligence. Intelligent orstudious children are called “geeks”, while intellectualmediocrity is regarded as “cool”. So shamelessly do thepopular media encourage this perception that it sometimesseems as though the human race is being systematically lulledinto a state of intellectual degeneracy. In your opinion, willthis trend ever be successfully counteracted? If not, what doyou foresee as the long-term effect on the distribution ofintelligence in the general population?Arthur Jensen: The trend you describe will be (or is alreadybeing) successfully counteracted in some other countries, andas a result, unless we soon get our own house in order, wellbe the losers--scientifically, culturally, and economically.There is nothing in the Book of Nature that says the USA isautomatically immune to the possibility of devolving towards 73
  81. 81. the conditions of Third World countries. The advancing frontof future civilization may well gravitate eastwardly. I cantsay I ever really understood Oswald Spengler, but the title ofhis famous book (Decline of the West, Ed.) seems prophetic. ButI dont worry about it as long as civilization will be preservedand developed somewhere on earth. 74
  82. 82. Question #24Chris Langan: There is a certain amount of evidencesupporting the hypothesis that intelligent people, being betterable to fill their lives without raising families, are havingfewer children. Unfortunately, for every socially responsible,intelligent person who decides to postpone or foregochildbearing, ten others, many with lesser geneticendowments, stand ready to fill his or her place in the genepool with their own progeny. Insofar as the net result wouldappear to be dysgenic, is it ethical to continue to let thishappen?Arthur Jensen: Yes, it is likely that there is a dysgenic trend ing level, at least in the USA. A plausible case can be garneredfrom U.S. Census data over the last 3 decades. I dont knowwhether it is or isnt ethical to neglect seriously investigatingthe possibility of a dysgenic trend or, if it indeed exists, to do 75
  83. 83. nothing about it. But a dysgenic trend that affects the overalllevel of g in the society would have ill-fated consequences forthis countrys future welfare, to say the least. Three facts haveto be much more generally understood: (1) There is a g factor,(2) the distribution and overall level of g in the population iscausally related to the level of civilization and the quality oflife in a modern society, and (3) g is highly heritable (i.e.,influenced by genetic factors). Given these facts, a conclusionregarding dysgenics would depend on examining birth ratesin different segments of the distribution of the g factor in thenations population. Depending on the conclusions from thisexamination, it will be up to informed public opinion and thepublic will need to decide what, if anything, should be done,or could be done, about it in our free society. 76
  84. 84. Question #25Chris Langan: Modern civilization grows increasinglydependent on complex technology, and thus on people withthe intelligence to design, implement and maintain it. Thisplaces a higher level of social utility on high intelligence, andthus on highly intelligent people. This brings to mind a ratherdepressing joke: “The problem with the gene pool is that thereis no lifeguard!” Would intellectual eugenics necessarily be abad thing for humanity? Is there a danger that this would leadto a Brave New World scenario?Arthur Jensen: Right on target! "Brave New World" is ofcourse pure science fiction, which is invariably based on thescience of the past and rarely imagines anything like theactual scientific and technological developments of the future.But there are even worse scenarios - dysgenic ones - than areportrayed in Huxleys novel. The lower one-fourth (perhaps 77
  85. 85. even the lower one-third) of the IQ distribution, as we knowits mental capabilities today, will have a hard time findinggainful employment of the kinds that are needed in a largelytechnological, information-intensive society. The USA isalready having to import workers, mostly from Asia, to fillthese kinds of positions, which would otherwise have to gobegging for applicants. A serious question that is hardly ever put up fordiscussion is whether a society should design itself in terms ofthe level of ability (largely g) and work demands that couldaccommodate the vast majority of its existing population orwork toward raising the overall level of ability toaccommodate the increasing ability demands of our trendtoward a more technological and information-intensivesociety. A number of symposia could be organized about thistheme. 78
  86. 86. Question #26Chris Langan: For some time now, Robert Plomin has beenlocating genes associated with high IQ. The evolution of thehuman genome project raises the possibility that even more ofthese genes will soon be located. Meanwhile, genetic testingand engineering technology promises to let people select theirmates for complementary genetic characteristics, and even to“upgrade” the DNA of their offspring in vitro. Do you see thisas harmful or beneficial to society?Arthur Jensen: American behavioral geneticist Robert Plomin(now a professor in the Behavioral Genetics Research Unit atthe Institute of Psychiatry in London, England), working witha large team of colleagues specializing in genetic research, hasalready identified several different sections of DNA (onchromosome #6) which reliably differ between large groups ofpeople of average IQ and of very high IQ. This research is 79
  87. 87. progressing at an accelerating rate as the technology foridentifying differences in specific sections of DNA (notnecessarily genes per se) is advancing rapidly. Inevitablymany more "IQ genes" will be identified within the very nearfuture. No one in the field is really surprised by Plominsfindings, because the heritability of IQ and of psychometric g(which is the main basis of IQ heritability) has long been wellestablished by the methods of quantitative genetics based onthe correlations of various kinships reared together andreared apart. The importance of Plomins research is that ityields specific information that will be used to trace thepathways of genetic expression, i.e., discovering just how theidentified genes chemically affect the development of thebrain variables that cause individual differences in g. It is anecessary complement to the approaches based on directstudies of brain physiology, affording clues that narrow thesearch for the key causal variables. Knowing precisely what agene does and how it does it is a major step towardunderstanding the workings of brain-behavior phenomena.The history of such advances in scientific knowledge stronglyindicates that they most usually prove beneficial to humanity. 80
  88. 88. Plomins effort, I believe, is one of the most worthwhilepursuits in present-day behavioral science. 81
  89. 89. Question #27Chris Langan: It was suggested some time ago thatpharmacological methods, e.g. neurotransmitter loading,could boost mental performance. More recently, the initialphase of the Human Genome Project has begun to give way tothe secondary “proteomic” phase, i.e. tracing the biochemicalpathways of genetic expression. As some of the involvedproteins are implicated in mental performance, new IQ-boosting drug therapies may be discovered. Is there anyreason to be interested in genetic intellectual endowmentwhen it may soon be possible for the under-endowed toswallow higher intelligence in the form of a pill?Arthur Jensen: One important advantage of the purelygenetic effects on the development of intellectual functions, incontrast to chemically induced effects in individuals, isobviously that the genetic effects can be transmitted naturally 82
  90. 90. from generation to generation, whereas the chemical effectsmust be continually reinstated anew in every generation. In aperiod of large-scale catastrophe many of those who weredependent on the chemical treatment would be deprived. Ithink it essential that the genetic mechanisms involved inmental abilities to be further researched, because even thediscovery of effective chemical interventions for improving apersons level of g will depend in large part on anunderstanding of the chemical pathways through which thegenes affect individual differences in g or other ability factorsthat may also be under genetic influence. 83
  91. 91. Question #28Chris Langan: Because genetic testing and engineering costsmoney, only the wealthy can easily afford it. This raises thepossibility that intelligence will become increasinglycorrelated with socioeconomic status…that the central thesisof the controversial bestseller The Bell Curve will be artificiallyamplified by genetic tampering. Do you see this as a potentialthreat to social stability?Arthur Jensen: This question raises serious concerns aboutthe extent to which, in a democratic society, the governmentshould be involved in control over science, its applications,and the lives of its citizens in general. The thesis of The BellCurve was met with paroxysms of denial and it is doubtfulwhether the problem posed in this question will, in thepresent political atmosphere, receive the kind of seriousdiscussion it deserves. The gap between the "haves" and "have 84
  92. 92. nots" in this country, to say nothing of the world at large, is, Ifear, already great enough to be "a potential threat to socialstability." 85
  93. 93. Question #29Chris Langan: Just as the human brain excels at certainintellectual tasks, computers excel at solving other kinds ofproblem. Hence, the idea of creating a superior intelligence bywiring together brain and machine. Do you regard as ethicalthis potentially dehumanizing “cyborg” approach tointellectual augmentation, which some regard as inevitable?Arthur Jensen: This still looks to me like science fiction. Manyof us are already quite tied to computers (I am in thatcondition at this very moment!), although not through anydirect line into the brains circuitry. That possibility sounds abit awful to me, but as a matter of principle I wont stop it if itbecame a reality. In my personal philosophy I tend to be "pro-choice" all the way, and I only hope we can preserve andpromote that freedom! 86
  94. 94. Question #30Chris Langan: As far as the evidence is concerned, theexistence of g is scientifically indisputable. But let’s face it: thisposes a problem for minorities possessing statistically less ofit per capita. After all, if it is simply accepted that the meanIQs for “colored” people and pure blacks are respectively oneand two standard deviations below the mean white IQ,employers and educators may be tempted to apply thesestatistics in vocational and academic contexts, effectivelyleading to “discriminatory” outcomes in which the minoritiesin question are “underrepresented”. Accordingly, certainremedial principles of social engineering are assigned ahigher priority than the psychometric findings themselves,resulting in reverse discrimination against qualified people ofEuropean and Asian ancestry. Given that this country is runby those with backgrounds in the social sciences rather thanin psychometrics, do you foresee any changes? 87
  95. 95. Arthur Jensen: I sense a growing tendency in our society infavor of treating all persons as individuals, and I believe thatincreasingly individual rights will trump group rights. Thegovernment itself should not discriminate on the basis of face,ethnicity, national origin, religion, sex, or sexual orientation. Ibelieve the same policy should be inculcated in the personalbelief system of all citizens. But of course this is one personsethical philosophy (and I hope also that of a vast majority ofAmericans), although it has nothing to do with scientificevidence. I believe that any kind of quotas or discriminationin education or employment opportunities based on anindividuals group membership rather than on thatindividual’s own characteristics only promote social conflictand instability. A just society can help people in need withoutresorting to discrimination on the basis of irrelevant criteriainvolving group-membership. It also promotes ill will andsocial unrest if members of minority groups have theperceptions that the majority is not making a very real effortto shun group discrimination and to treat people strictly as so-called "Americas race problem." 88
  96. 96. Question #31Chris Langan: You’re working on a new book. Can youplease tell us briefly what the working title is and what it willcover?Arthur Jensen: The working title of the book I am presentlywriting is "Mental Chronometry and Individual Differences."It is not conceived as a "trade book" in the least, but will be ahighly specialized and technical treatise for advancedstudents and professional doing research in this field, orwanting to learn more about it. Mental chronometry bridgesthe interface of brain and behavior and can benefit both ofthese subjects of inquiry. To get a better hold on brain-behavior connections, we need better behavioral measures ofindividual differences than are provided by our presentpsychometric tests that have no true scale and can only rank-order individuals. As mentioned several times in response to 89
  97. 97. previous question regarding measurement problems, I believewe must measure individual differences in mental abilities bymeans of true ratio scales, and these can be made possiblewith mental chronometry. Models of brain activity built onthe time taken by various mental functions are already avenerable area of research in experimental psychology andcan provide a basis for exploring the nature and dimensionsof individual differences. The burgeoning research literatureon this is already surprisingly vast, and it is a big job justgetting it under control, even though I have been working inthis area for some 20 years. This research requires very specialinstrumentation (now greatly aided by computers), andindividual testing of subjects under highly controlledlaboratory conditions. The time measurements obtained makemuch more sense in relation to physiological and electro-physiological brain measurements than do the ordinal-scalescores on psychometric tests. We are dealing here withmeasurements in milliseconds, mostly in the range below oneor two seconds. These chronometric methods are of interestnot only in experimental and differential psychology, but arebeing increasingly used in medical diagnosis and treatment. 90
  98. 98. Chronometric variables are fare more sensitive to subtle drugeffects than are any psychometric tests. Chronometricmethods also can detect insidious brain conditions long beforethey can be recognized through subjective self-awareness,gross behavioral observations, or conventional psychologicaltesting. However, as a useful tool for studying individualdifferences in both their normal and abnormal aspects, mentalchronometry is still in its bare infancy. I believe it shouldbecome a major branch of behavioral science, and I hope myprojected book will help it along this path. 91
  99. 99. Christopher Langan and Gina LoSassoAbout the Mega FoundationChristopher Michael Langan was identified as “severelygifted” while still a young child. As he grew up, he wasnevertheless challenged with inadequate schooling, extremepoverty, bouts of severe abuse, and the responsibility ofhelping care for his younger siblings. Raised to value brawnas highly as brains, Christopher worked at various times as acowboy, firefighter and construction worker, and for the past20+ years, as a bar bouncer in assorted nightclubs across the

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