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AT PRESENT, IT IS IMPOSSIBLE TO KNOW THE DEGREE OF GENETIC DETERMINATION OF INDIVIDUAL CHARACTERISTICS, IE, THEIR HERITABILITY. MAJOR PROBLEMS OF RELIABILITY ARE MANIFOLD. A CHILD WITH GENOTYPICALLY HIGH INTELLIGENCE MAY MAGNIFY HIS ADVANTAGE BY SHAPING HIS OWN ENVIRONMENT, WHICH THUS MAY BECOME MORE RESPONSIVE TO HIS NEEDS. A CHILD WITH GENOTYPICALLY LOW INTELLIGENCE, BEING AT A DISADVANTAGE, MAY NOT RESPOND TO HIS OWN ENVIRONMENT IN WAYS WHICH CAN AMPLIFY HIS EXPERIENCES. THIS RAISES A QUESTION AS TO THE JUSTICE OF ADULT RESPONSE TO CHILDREN WHICH ENCOURAGES SOME & DISCOURAGES OTHERS. NO MEANINGFUL ESTIMATE OF THE IMPORTANCE OF SUCH INDIRECT GENETIC EFFECTS CAN BE MADE. WHERE IQ IS CONCERNED, IQ'S HERITABILITY MAY BE CALCULATED EVEN THOUGH WE DO NOT KNOW WHAT IQ REALLY IS, OR WHAT VALUE IT HAS. HERITABILITY ESTIMATES ARE USEFUL ONLY IN THAT THEY RELATE TO POSSIBILITIES FOR CHANGE IN PRESENT CIRCUMSTANCES; THEY HAVE NO FUNCTION IN PREDICTING POTENTIAL CHANGES ARISING FROM NEW ENVIRONMENTAL SITUATIONS. WHERE DYSGENICS IS CONCERNED, GIVEN THE SUSPICION THAT IQ TESTS HAVE LIMITED VALUE IN JUDGING INTELLIGENCE, ANY EUGENIC PROGRAM SEEMS FRAUGHT WITH PROFOUND MORAL QUESTIONS. ARGUMENTS REGARDING SOCIAL STRATIFICATION & ITS INEVITABLE STRENGTHENING THROUGH GENETIC REINFORCEMENT ARE SOPHISTICATED BUT FALLACIOUS. WHILE SOME R DOES SEEM TO EXIST BETWEEN IQ & SOCIAL STANDING, THIS MIGHT BE DETERMINED BY A GREAT MANY NONGENETIC FACTORS RELATING TO THE ENVIRONMENT WHICH STATUS & MONEY IN OUR SOCIETY PROVIDE. SUCH IDEOLOGICAL & RACIST OVERTONES IN HERITABILITY DISCUSSIONS RAISE SERIOUS QUESTIONS OF SCIENTIFIC ETHICS; THE WIDE DISSEMINATION & POSSIBLE MISINTERPERTATIONS OF THEIR CONCLUSIONS ARE MAJOR PROBLEMS. SCIENTISTS DO HAVE A CERTAIN OBLIGATION TO CONSIDER THE MORAL IMPLICATIONS OF THEIR RESEARCH & THE POSSIBLE MISUSE OF RESULTS. STUDIES OF HERITABILITY OF IQ SHOULD CERTAINLY CONTINUE; STUDIES WHICH EMPLOY RACE AS THEIR MAJOR VARIABLE, HOWEVER, PARTICULARLY IN VIEW OF OUR TREMENDOUSLY IMPERFECT KNOWLEDGE OF THE VALUE OF IQ, SHOULD BE STOPPED. 1 FIGURE. C. LELAND.

A NEW LOOK AT THE CONCEPT OF 'INTELLIGENCE TESTS' IS REQUIRED, IN VIEW OF THE CONTROVERSIAL 'GENETIC INEQUALITY OF THE RACES' & 'STERILIZATION OF THE LOW IQ' THEORIES FOSTERED IN SOME PLACES TODAY. INTELLIGENCE IS MOST AMBIGUOUSLY DEFINED, YET POPULARLY SO, AS "WHAT IQ TESTS MEASURE." THIS LACK OF CLEAR DEFINITION FOR THE TERM IMPLIES A REAL LACK OF A THEORY OF INTELLIGENCE & AN ATTENDANT VALIDITY QUESTION IN REGARD TO WHAT IQ TESTS DO MEASURE. SOME R DOES EXIST BETWEEN THE IQ TEST SCORE & SUCCESS IN SCHOOL & SOCIETY, BUT ARE WE REALLY MEASURING INTELLIGENCE WITH IQ TESTS, OR IS IT FACTORS OF MOTIVATION, 'TEST-WISENESS', CULTURAL BACKGROUND, ETC? IQ TESTS ARE FOUNDED ON AN UNSTATED THEORY: THEY TEST KNOWLEDGE & DEVELOPED SKILLS ON THE ASSUMPTION THAT THOSE QUALITIES MEASURE INTELLIGENCE. THEY MAKE NO ALLOWANCES FOR THE DIFFERENTIAL IN SUBJECT'S ACCESS TO INFORMATION, OR FOR VARIABLES IN MOTIVATION, INTEREST, ETC. NO ACCOUNT IS TAKEN OF INDIVIDUAL'S VARYING CAPACITIES TO DEMONSTRATE KNOWLEDGE OF THE TYPE DEMANDED BY THE TEST, WHILE SUCH ASPECTS OF INTELLIGENCE AS CREATIVITY ARE IGNORED ENTIRELY. THE TESTS ASSUME THE EXISTENCE OF 'GENERAL INTELLIGENCE'--SOMETHING LIKE ABSTRACT REASONING ABILITY--DESPITE THE FACT THAT PSYCHOMETRICIANS THEMSELVES ARE DEEPLY DIVIDED AS TO THE EXISTENCE OF THIS ENTITY. 3 FIGURES. C. LELAND.

Using a small sample of monozygotic and same-sex dizygotic twins, estimates of the heritability of certain parameters of sexual development were obtained. In the majority of instances significant values of h2 were found, suggesting that genetic factors play an important role in psychosexual development. The significance of these results is discussed in the light of current pro-environmental attitudes.

With a sample of stemmed projectile points, the nonredundant description of archeological characteristics is demonstrated by principal‐axes factor analysis. The obtained dimensions of the artifacts are tested for cultural significance by variance techniques. The concept of "culturability," or c2, is introduced as the total predictable variance of a measurement of an artifact from a knowledge of its location in time and space. Both the psychologically derived factor‐analytic model and c2, analagous to the concept of heritability in population genetics, are found to be useful in interpreting archeological data. The use of available programs and high‐speed digital computers allows a complete analysis with a small expenditure of time.

A critical examination is undertaken of the major arguments which have been advanced in support of the hyp that the 15-point X IQ gap between black & white Amer's is largely determined by genetic factors, & the conclusion is reached that they are all specious & valid. The a priori argument, which suggests that it is highly likely that such genetic diff's between the 2 pop's do exist, is shown to be illogical on 2 counts & based on an empirically unsubstantiated premise; furthermore, a more persuvsive a priori hyp in the opposite direction is formulated & defended. Attention is called to the much-neglected direct evidence, based on comparisons of the IQ scores of black people with known %'s of white ancestry, & it is shown that this evidence does not confirm the genetic hyp. The argument from compensatory educ is examined, & it is pointed out that the evidence is irrelevant even if it is reliable. The heritability argument, which is based on the findings of twin studies, is challenged by the evidence on intrauterine effects on later intellectual development, which make possible a plausible non-genetic interpretation of the findings of twin studies, & by the logical point that the heritability of a character within a pop does not bear on the origin of diff's between pop's. 2 versions of the "culture fairness" argument are criticized on the grounds that they ignore the most signif environmental influences of performance in IQ tests among the various minority groups in the US, & also pay no attention to the phenomenon of "passing for white." Finally, the ideological character of the geneticist doctrine is examined, with particular reference to the writings of A. R. Jensen (see SA 0312/B4540) & H. J. Eysenck (RACE INTELLIGENCE AND EDUCATION, London, England: Temple Smith, 1971). AA.

Data are presented on the verbal and performance (non-verbal) IQs of a sample of university scientists, their surviving fathers and male sibs.Although mean IQs differ between scientific disciplines the disciplines do not differentially attract scientists from particular socio-economic classes.The verbal IQs of both the scientists and their fathers are positively correlated with socio-economic class but only in the fathers' sample is the performance IQ/class correlation significant. The variance of both verbal and performance IQs increases from Class I to Class IIIM. The overall estimate of heritability for the verbal IQ is higher than that for the performance IQ.Verbal and performance IQs are related to the distance the scientists have moved on the socio-economic scale. The effects of social mobility on the genetic and environmental components of the verbal and performance IQ phenotypic variances are discussed.

The debate about the 'heritability' of IQ will remain inconclusive, it is argued, until we possess vastly more knowledge about (i) the assessment of intellectual skills, (ii) the human environment that facilitates their growth, & (iii) the rapidly evolving culture that lends them shape & meaning. Res interests & educ'al responsibilities coincide here. Both require that we learn to maximize each individual's use of his mental powers, irrespective of the class or race from which he comes. A general law is postulated; Hudson's Law of Selective Attention to Data in Arthur Jensen's review (see SA 0312/E4540) 1969 is taken as a test case of the Law's action; in particular, the account given in it of the genetic abnormality Turner's syndrome, claimed to be 'one of the most striking pieces of evidence for the genetic control of mental abilities.' Detailed reference to the original source shows that the evidence about Turner's syndrome is systematically misrepresented. The lack of normal sexual development in sufferers from the syndrome is ignored, likewise their frequent, gross physical deformities. The confused genetic basis of the syndrome is oversimplified. The small size of the sample is not mentioned, the disparity of ages is ignored, likewise the use, over a 10-yr span, of 3 diff IQ scales. It is claimed that the ability of patients in spatial reasoning is uniformly low. The original evidence contradicts this; & in fact, in a substantial minority of cases, spatial reasoning ability actually equals verbal reasoning or exceeds it. Finally, 'space form blindness' among sufferers is represented as specific; in fact, where weaknesses occur they encompass the whole non-verbal range. Further, obvious soc psychol'al & sociol'al interpretations of the data are ignored. What is lacking is an appropriate model for res into ideological sensitive issues: one which allows both for the interaction of O & observed, & for the interaction of the exp'er's presuppositions with the more formal aspects of his res. Modified AA.

SUMMARY The question of the genetic or environmental determination of human development has always been controversial. Intelligence tests, which assume a very large genetic component continue to be used frequently in the West and increasingly in the developing world as a tool for legitimating the allocation of persons to rôles in society. The results from intelligence tests are also used to demonstrate and explain racial and societal differences in intellectual development. The statistic at the centre of the debate, heritability, is invariably misinterpreted and is of more limited use than many would wish to believe.RESUME Les statistiques et I' "héritocratie"La détermination de l'évolution humaine, sur le plan génétique ou de l'environnement constitute un problème qui a toujours suscité des controverses. Les tests de capacité intellectuelle, censés faire partie très importante de la génétique, continuent à servir, fréquemment dans les pays de l'Ouest et de plus en plus dans le tiers‐monde, aux fins de justifier la désignation de certains individus à des rales spécifiques dans la société. On se sert également des résultats de tests de capacité intellectuelle pour démontrer et expliquer les divergences raciales et d'ordre social dans le développement intellectuel. L'élément statistique sur lequel se concentre le débat, à savoir la transmissibilité. devient infailliblement l'objet d'interprétation trompeuse.RESUMEN Las estadísticas y la heritocraciaLa cuestión de la determinación genética o ambiental del desarrollo humano ha sido siempre objeto de controversia Los tests de inteligencia, que suponen un componente genético muy grande, siguen siendo usados frecuentemente en Occidente y cada vez más en los países en desarrollo como herramienta para legitimar la asignación de personas a diversos roles en la sociedad. Los resultados de tests de inteligencia también se usan para demostrar y explicar diferencias raciales y sociales en el desarrollo intelectual. La estadística que es centro del debate, a saber, la transmisión hereditaria, se interpreta invariablemente en forma errónea y es de uso más limitado de lo que muchos quisieran creer.