The letter to The Wall Street Journal set out 25 conclusions:
- "Intelligence is a very general mental capability ... it reflects a broader and deeper capability for comprehending our surroundings ..."
- "Intelligence, so defined, can be measured, and intelligence tests measure it well. They are among the most accurate (in technical terms, reliable and valid) of all psychological tests and assessments."
- "While there are different types of intelligence tests, they all measure the same intelligence."
- "The spread of people along the IQ continuum ... can be represented well by the ... ‘normal curve'."
- "Intelligence tests are not culturally biased"
- "The brain processes underlying intelligence are still little understood"
- "Members of all racial-ethnic groups can be found at every IQ level...The bell curves for some groups (Jews and East Asians) are centered somewhat higher than for whites in general. Other groups (blacks and Hispanics) are centered somewhat lower than non-Hispanic whites."
- "The bell curve for whites is centered roughly around IQ 100; the bell curve for American blacks roughly around 85; and those for different subgroups of Hispanics roughly midway between those for whites and blacks. The evidence is less definitive for exactly where above IQ 100 the bell curves for Jews and Asians are centered"
- "IQ is strongly related, probably more so than any other single measurable human trait, to many important educational, occupational, economic, and social outcomes ... Whatever IQ tests measure, it is of great practical and social importance"
- "A high IQ is an advantage because virtually all activities require some reasoning and decision-making"
- "The practical advantages of having a higher IQ increase as life’s settings become more complex"
- "Differences in intelligence certainly are not the only factor affecting performance in education, training, and complex jobs ... but intelligence is often the most important"
- "Certain personality traits, special talents, [etc] are important ... in many jobs, but they have narrower (or unknown) applicability or ‘transferability’ across tasks and settings compared with general intelligence"
- "Heritability estimates range from 0.4 to 0.8 ... indicating genetics plays a bigger role than environment in creating IQ differences"
- "Members of the same family also tend to differ substantially in intelligence"
- "That IQ may be highly heritable does not mean that it is not affected by the environment ... IQs do gradually stabilize during childhood, however, and generally change little thereafter"
- "Although the environment is important in creating IQ differences, we do not know yet how to manipulate it"
- "Genetically caused differences are not necessarily irremediable"
- "There is no persuasive evidence that the IQ bell curves for different racial-ethnic groups are converging"
- "Racial-ethnic differences in IQ bell curves are essentially the same when youngsters leave high school as when they enter first grade ... black 17-year-olds perform, on the average, more like white 13-year-olds"
- "The reasons that blacks differ among themselves in intelligence appear to be the same as those for why whites ... differ among themselves"
- "There is no definitive answer as to why bell curves differ across racial-ethnic groups. The reasons for these IQ differences between groups may be markedly different from the reasons for why individuals differ among themselves within any particular group"
- "Racial-ethnic differences are somewhat smaller but still substantial for individuals from the same socio-economic backgrounds"
- "Almost all Americans who identify themselves as black have white ancestors – the white admixture is about 20% ... research on intelligence relies on self-classification into distinct racial categories"
- "The research findings neither dictate nor preclude any particular social policy, because they can never determine our goals. They can, however, help us estimate the likely success and side-effects of pursuing those goals via different means."
Περισσότερα, εδώ.
Intelligence is a very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience. It is not merely book-learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surroundings "catching on," "making sense" of things, or "figuring out" what to do.