Arthur Jensen has argued that genetic differences in abstract reasoning ability, not cultural bias in the test item, are the causes of differences in standardized test performance between American Blacks and Whites. He used a study by Frank McGurk to support his argument. McGurk's study used test items judged most cultural or least cultural. These…

This paper repudiates Jensen's hypothesis that differences in IQ scores and scholastic achievement in Negro and white children are genetically based. Specifically, Jensen's identification of IQ scores as a measure of abstract reasoning and problem solving and of levels of ability, and his evaluation of the magnitude of the genetic component in IQ…