Research has shown that differences among ordinary people in intelligence and personality depend equally on individual genetic variability and on differences in the environments that siblings experience within the same family, not differences in the neighborhood, school, and community environments. As of yet, there are no adequate theories to…

Reviews the furor and reaction to Arthur Jensen's controversial genetic theory of intellectual differences. The cases of Shockley, Eysenck, and Herrnstein are also discussed as instances in which intellectual debate was supplanted by academic persecution and impassioned rhetoric. (EH)

Intelligence tests were administered to a stratified sample of 4058 school children from Palermo, Sicily. I.Q. scores were found to be positively correlated with socioeconomic status and negatively related to family size. As birth order increased, mental development decreased. Implications for future research were discussed. (EH)

Authors were invited to comment on the implications for the British teacher of Jensen's article. (Editor/MB)

From the monthly Saturday Review supplement, "Education in America, sponsored by the Charles F. Kettering Foundation.

The purpose of this paper is to clarify some of the conceptual issues involved in discussions of psychology and education which rely on the assumption that biological factors serve as a basis or are responsible for human intelligence. (Author/ND)

Comparing group intelligence according to racial or geographic orgin has neither social nor scientific value; the emphasis in education and the social economy is not the creation of equality but the development of each individual to his maximum performance. (Author/JM)

Findings from a study reported in this paper indicate that the differences in family background that affect IQ are largely the result of genetic differences among parents, which affect the parents' own status attainment and which are passed on genetically to their offspring, whose status attainments are subsequently affected. (Author/EB)

"The Bell Curve" declares that studies of separated identical twins--the "purest" of "direct" methods for estimating IQ heritability--indicate a value of +.75-+.80. But, the main study cited suggests a heritability of "two-thirds" for the middle class, and Herrnstein and Murray neglect to mention numerous…

Finds that the available data for the heretability of intelligence is inadequate to settle the question conclusively. Argues that the benefits of diversity can only be realized if equality of opportunity is complimented by equality of status. (EH)

This paper presents the results of a study which examined heritability ratios for the major ethnic and socioeconomic groups in the Los Angeles Unified School District. Scores on three measures (the Cooperative Primary Reading Test, the Comprehensive Test of Basic Skills, and a composite set of intelligence tests) were compared for twins from…

A classification of natal influences is proposed with a model of their operation. Natal influences affect maternal capacity, maternal load, and maternal efficiency. Since maternal load is increased in twin pregnancy, results of twin studies must be generalized with caution. The method of co-twin control is exemplified by examination of a small…