Hockenbury Discovering Psychology 5th txtbk

298 CHAPTER 7 Thinking, Language, and IntelligencevalidityThe ability of a test to measure what it isintended to measure.g factor or general intelligenceThe notion of a general intelligence factorthat is responsible for a person’s overallperformance on tests of mental ability.ValidityFinally, a good test must demonstrate validity, which means that the test measureswhat it is supposed to measure. One way to establish the validity of a test is bydemonstrating its predictive value. For example, if a test is designed to measuremechanical aptitude, people who received high scores should ultimately prove moresuccessful in mechanical jobs than people who received low scores.The Nature of IntelligenceKey Theme• Psychologists do not agree about the basic nature of intelligence, includingwhether it is a single, general ability and whether it includes skills andtalents as well as mental aptitude.Key Questions• What is g, and how did Spearman and Thurstone view intelligence?• What is Gardner’s theory of multiple intelligences?• What is Sternberg’s triarchic theory of intelligence?The Wechsler Adult Intelligence Scale and the Stanford-Binet Intelligence Scaleare standardized, reliable, and valid. But do they adequately measure intelligence?The question is not as simple as it sounds. There is considerable disagreementamong psychologists about the nature of intelligence, including how intelligenceshould best be defined and measured (Neisser & others, 1996; Shavinina,2001).Take another look at the chapter Prologue about Tom and his family. In termsof the type of intelligence that is measured by IQ and other standardized tests, Tomis extremely intelligent. But despite his high IQ, Tom can find it extremely difficultto carry out many activities that those with a more “normal” or average intelligencecan perform almost effortlessly. Applying for an after-school job, joining a conversationthat is already in progress, or even knowing why—or whether—a particularjoke is funny are very difficult, if not impossible, tasks for Tom. As you’ll see in thenext section, psychologists have struggled with the challenge of how to defineintelligence for over a century.Theories of IntelligenceMuch of the controversy over the definition of intelligence centers on two keyissues. First, is intelligence a single, general ability, or is it better described as a clusterof different mental abilities? And second, should the definition of intelligence berestricted to the mental abilities measured by IQ and other intelligence tests? Orshould intelligence be defined more broadly?Although these issues have been debated for more than a century, they are farfrom being resolved. In this section, we’ll describe the views of four influential psychologistson both issues.Charles SpearmanIntelligence Is a General AbilitySome psychologists believe that a common factor, or general mental capacity, is atthe core of different mental abilities. This approach originated with British psychologistCharles Spearman. Although Spearman agreed that an individual’sscores could vary on tests of different mental abilities, he found that the scores on