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Brun_0471443956_4p_09_r1.qxd 6/27/02 1:46 PM Page 134 134 PSYCHOLOGY 4. Step-by-step instructions for operating a microwave oven provide an example of a. a heuristic approach b. a means-end analysis c. an algorithm d. an insight analysis 5. Let’s say you figure out the square root of 12 without a formula. Instead, you rely on your understanding of the concept of a square root. What kind of a problem-solving approach are you using? a. An algorithm b. A heuristic approach c. A means-end analysis d. An operant reflection 6. Which of the following correctly defines a mental set? a. A conscious conditioned reflex b. An unconscious wish c. A subconscious determining tendency d. A false negative 7. What exists when there is a need to use a tool or familiar object in a novel way and one can’t perceive the novel way? a. Cognitive slippage b. Mental facilitation c. Functional fixedness d. Transformational perception 8. What kind of reasoning is characterized by making observations and gathering information until a general conclusion is reached? a. Inductive reasoning b. Deductive reasoning c. If-then reasoning d. Relational reasoning 9. Deductive reasoning is reasoning in which a. a premise follows from a conclusion b. a premise follows from a hyperpremise c. a conclusion follows from a metaconclusion d. a conclusion follows from a premise 10. What is the core feature of the creative process? a. Convergent thinking b. Divergent thinking c. Congruent thinking d. Reliable facts Brun_0471443956_4p_09_r1.qxd 6/27/02 1:46 PM Page 135 Thinking: Exploring Mental Life 135 ANSWERS TO THE SELF-TEST 1-d 2-d 3-a 4-c 5-b 6-c 7-c 8-a 9-d 10-b ANSWERS TO THE TRUE-OR-FALSE PREVIEW QUIZ 1. True. 2. True. 3. False. Heuristic approaches employ principles, rules-of-thumb, and insights to solve problems. 4. False. It is correct that functional fixedness is a type of mental set. However, functional fixedness exists when there is a need to use a tool or familiar object in a novel way and one can’t perceive the novel way. Consequently, such fixedness interferes with solving a problem. 5. False. The core feature of the creative process is divergent thinking. KEY TERMS algorithm inductive reasoning analogy logical thinking appeal to authority means-end analysis arguing in circles mental set attack on character metathought concept negative exemplar conjunctive concept originality convergent thinking overgeneralization deductive reasoning paleological thought definition of the problem positive exemplar disjunctive concept predicate thinking divergent thinking preparation false analogy productive thinking false assumption productivity flexibility rational thought functional fixedness relational concept hasty generalization symbol heuristic approaches thinking illumination verification incubation Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 136 10 Intelligence: In Pursuit of Rational Thought and Effective Action PREVIEW QUIZ True or False 1. T F The concept of intelligence is associated with the ability to think clearly and to function effectively in the environment. 2. T F The Stanford-Binet Intelligence Scale is based on the performance method of measuring intelligence. 3. T F Information, or general knowledge, is not associated with intelligence. 4. T F An intelligence quotient (IQ) score of 100 is evidence of superior intelligence. 5. T F A valid test is one that measures what it is supposed to measure. (Answers can be found on page 152.) Thinking, the subject matter of the previous chapter, plays a significant role in intelligence. Indeed, as the subtitle of this chapter suggests, rational thought is at the core of intelligence. We will now examine the concept of intelligence and the ways in which it can be measured. 136 Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 137 Intelligence: In Pursuit of Rational Thought and Effective Action 137 Objectives After completing this chapter, you will be able to • • • • • define intelligence; describe the approach of the Stanford-Binet Intelligence Scale; specify key features of the Wechsler Intelligence Scales; explain the concept of an intelligence quotient (IQ); compare and contrast the concepts of validity and reliability in psychological testing. Consider how you might use the word intelligent in a short sentence. Here are some answers that were obtained from members of an introductory psychology class: “I want to marry an intelligent person.” “Is there intelligent life on Earth?” “I want to raise intelligent children.” “To be intelligent is both a curse and a blessing.” “It’s difficult to make intelligent decisions.” “I always have the feeling that that my friends are more intelligent than I am.” “I’m intelligent when it comes to math, but not in my way of relating to other people.” As you can see from these statements, the concept of intelligence is a pervasive one entering into most aspects of behavior and life. Although the concept of intelligence is as familiar, in a way, as an old shoe, it has a quality of mystery about it. Familiarity should not breed contempt in this case. We shouldn’t be confident that we really understand intelligence until we explore its more important features. Intelligence: What Is It? Intelligence is the global ability of the individual to think clearly and to function effectively in the environment. This definition of intelligence is based on the thinking and writing of the clinical psychologist David Wechsler (1896–1981), author of the widely used Wechsler Intelligence Scales. (There will be more about the Wechsler Scales later.) Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 138 138 PSYCHOLOGY If we examine the definition clearly, several important points emerge. First, intelligence is, to some extent, global. This means that it has a general quality that has an impact on many facets of life. When we think of someone as “smart,” we expect him or her to be a smart businessperson, a smart parent, a smart student, and so forth. (Subsequently we will reexamine the global, or general, nature of intelligence and compare it with specific mental abilities.) Second, intelligence is associated with the ability to think clearly. This means the ability to use both inductive and deductive logic in an appropriate manner. The core feature of intelligence, unlike creativity, is the ability to employ convergent thinking, defined in chapter 9 as the ability to think along conventional pathways. When a question is asked on an intelligence test, there is only one best answer. Consequently, intelligence tests measure convergent thinking. When one learns the basic information associated with a trade or profession, one is required to learn well-established facts and principles. (a) Intelligence is the global ability of the individual to think in the environment. and to function (b) The core feature of intelligence, unlike creativity, is the ability to employ what kind of thinking? Answers: (a) clearly; effectively; (b) Convergent thinking. Third, intelligence implies the ability to function effectively in the environment. A person with normal intelligence has survival skills. He or she can get things done correctly—everything from pumping gas to cooking a meal. The word environment includes almost any aspect of an individual’s surrounding world. Therefore, it includes the social environment, the world of other people. A person with normal intelligence is able to get along reasonably well with others. Note that the definition of intelligence says nothing about heredity and environment. The concept of intelligence, in and of itself, is a functional one. It refers to what a person can do. The question of how heredity and environment contribute to intelligence is, of course, an important one, and is treated in a later section in this chapter. Returning to the global aspect of intelligence, in the first decade of the twentieth century the British researcher Charles Spearman concluded that there is a general factor running through all aspects of intelligence. He called this general factor g. Spearman also recognized that there were specific mental abilities, and he called this factor s. (a) The word includes almost any aspect of an individual’s surrounding world. (b) The concept of intelligence is a one. It refers to what a person can do. Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 139 Intelligence: In Pursuit of Rational Thought and Effective Action (c) Spearman concluded that there is a intelligence. He called this factor 139 factor running through all aspects of . Answers: (a) environment; (b) functional; (c) general; g. Interested in the nature of specific mental abilities, the American researcher Louis Thurstone made a factor analysis of intelligence tests in the 1930s. Factor analysis is a mathematical tool that allows a researcher to pull meaningful clusters out of a set of data. Based on his analysis, Thurstone concluded that there are at least nine primary mental abilities. These include (1) inductive reasoning, (2) deductive reasoning, (3) word fluency, (4) speed of perception, (5) verbal comprehension, (6) verbal fluency, (7) memory, (8) spatial visualization, and (9) mathematics. More recently, the research psychologist Howard Gardner has suggested that we speak of multiple intelligences in preference to global intelligence. Taking this approach, one kind of intelligence may be more or less independent of another kind of intelligence. An example of what Gardner means is kinesthetic intelligence, the ability to comprehend the position of one’s body in space. Such intelligence is important in athletic performance and dancing. (a) What kind of analysis did Thurstone make of intelligence tests? (b) Gardner has suggested that we speak of intelligence. in preference to global Answers: (a) A factor analysis; (b) multiple intelligences. It is possible to bring together the concept of a general ability with the concept of specific abilities. The general factor, or g, is like the palm of a hand. It can be small or large. The specific abilities are like the fingers of a hand, and they can vary in length. This allows for many possibilities. Kurt has an unusually high level of general intelligence, but finds it difficult to comprehend mathematical concepts. Rita has an average level of general intelligence; however, she makes her living as a sculptor, and she displays an unusually high level of ability in the area of spatial visualization. As you can see, it is difficult to pin intelligence down and say with any kind of finality what it is. This in part is due to the fact that intelligence has the status of a hypothetical construct. In science, a hypothetical construct is “constructed” by the mind of the scientist in order to explain a set of facts. In physics, the concept of an electromagnetic field is sometimes said to be such a construct. Science freely employs hypothetical constructs. Intelligence as experienced by you is not, of course, hypothetical. However, intelligence as measured by a psychologist with an intelligence test is hypothetical. The intelligence has to be inferred from scores, and Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 140 140 PSYCHOLOGY there is room for error whenever one makes an inference. (See the section on validity and reliability on pages 145–147.) (a) It is possible to bring together the concept of a general ability with the concept of abilities. (b) In scientific terms, intelligence has the status of a (c) Intelligence has to be construct. from scores. Answers: (a) specific; (b) hypothetical; (c) inferred. The Stanford-Binet Intelligence Scale: Intelligent Is as Intelligent Does One of the first people to attempt to measure intelligence in an objective manner was the English scientist Sir Francis Galton (1822–1911). Working somewhat over one hundred years ago, he used the biometric method, meaning he tried to measure intelligence directly by evaluating such physiological measures as strength of grip and perceptual-motor speed. He found that there was little correlation between these measures and intelligence. Discouraged, he discontinued his research in this particular area of human behavior. Only a few years after Galton abandoned the effort to measure intelligence, Alfred Binet, director of the psychological laboratory at the Sorbonne in Paris, was asked by France’s Minister of Public Instruction to devise a way to detect subnormal intelligence. The aim was to give extra instruction and assistance to children with cognitive problems. Binet, working in collaboration with the scientist Theodore Simon, published the Binet-Simon Scale in 1905. This was the first modern intelligence test, and today’s tests still use its basic method—the performance method. In brief, the subject is asked to demonstrate the existence of intelligence by giving answers to questions. Correct answers reflect the existence of intelligence. Informally, the Binet-Simon Scale was based on the premise that intelligence is as the intelligent individual does. (a) What method did Galton use in his unsuccessful attempt to measure intelligence? (b) What method did Binet and Simon use in their successful attempt to measure intelligence? Answers: (a) The biometric method; (b) The performance method. Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 141 141 Intelligence: In Pursuit of Rational Thought and Effective Action The Binet-Simon Scale established a measure called mental age, or MA. Mental age is determined by comparing one subject’s score on the Binet-Simon Scale with the scores of a group of subjects of the same age. Let’s say that a group of nineyear-old subjects is able, on average, to answer fifteen questions correctly on the Scale. If seven-year-old Alice is able to answer fifteen questions correctly, her mental age is nine even though her chronological age is seven. Binet and Simon expected mental age to rise over time, and it does. In view of the fact that mental age is a changeable number, this created a problem. (The way in which this problem was solved with the concept of an intelligence quotient, or IQ, will be discussed later.) The Binet-Simon Scale was translated into English by the Stanford psychologist Lewis Terman. In 1916, only eleven years after Binet and Simon published their test, the Stanford-Binet Intelligence Scale (SBIS) was published in the United States. The SBIS became a popular way in which to measure intelligence, and it is still used today in revised form. One of the questions that interested Terman was: Do highly intelligent children do, overall, better in life than children of normal intelligence? In order to answer the question, Terman started a longitudinal study, a research project that measures behavior over a span of time. In this case, the Stanford project, carried on after Terman’s death, continued for more than seventy years. The results are clear. On the whole, highly intelligent children grew into highly intelligent adults. They fared better in general in all aspects of life. They had better health, fewer divorces, and better mental and emotional adjustment than subjects with average intelligence. This result should not be surprising. If intelligence is to mean anything at all as a concept, it must mean that it has value to the individual and society. As already indicated in the definition of intelligence, the ability to think clearly and to function effectively is part and parcel of what it means to be intelligent. (a) What measure, abbreviated MA, is associated with the Binet-Simon Scale? (b) Terman translated the Binet-Simon Scale into English and called it . (c) A research project that measures behavior over a span of time is called what kind of a study? Answers: (a) Mental age; (b) the Stanford-Binet Intelligence Scale (SBIS); (c) A longitudinal study. The Wechsler Scales: Comparing Verbal Intelligence and Performance Intelligence Working for a number of years as the chief psychologist for the Bellevue Psychiatric Hospital in New York City, David Wechsler conducted a substantial amount Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 142 142 PSYCHOLOGY of research on intelligence. His work culminated in a set of highly regarded intelligence tests called collectively the Wechsler Scales. There are three individual tests, and in revised editions they are still used today. The three tests are: (1) the Wechsler Preschool and Primary Scale of Intelligence (WPPSI), (2) the Wechsler Intelligence Scale for Children (WISC), and (3) the Wechsler Adult Intelligence Scale (WAIS). The Wechsler Scales have a clear-cut advantage over the Stanford-Binet Scale. The Stanford-Binet measures general intelligence without regard to specific mental abilities. The Wechsler Scales recognize that there are different kinds of intelligence. Two in particular are emphasized: verbal intelligence and performance intelligence. Verbal intelligence includes such abilities as word fluency, abstract reasoning, and mathematical ability. Performance intelligence includes such abilities as visualization, the perception of the relationship of parts to a whole, and the capacity to relate well to other people. As a consequence, it is possible to obtain two separate IQ scores, a verbal IQ and a performance IQ. The two IQ scores can be combined for an overall IQ score. (a) What does the abbreviation WAIS stand for? (b) What two kinds of intelligence are clearly identified in the Wechsler Scales? Answers: (a) Wechsler Adult Intelligence Scale; (b) Verbal intelligence and performance intelligence. The following description is based on the Wechsler Adult Intelligence Scale. Not only is the Scale divided into two large areas, it is also subdivided into a set of eleven subtests, six under the Verbal Scale and five under the Performance Scale. Keep in mind that the word scale is used because sets of questions proceed from easy to difficult. Evaluation is based on how high the subject can climb on the ladder of psychological difficulty. Here is the breakdown: The Verbal Scale: Each of the following tests consists of a group of questions designed to assess a different area. Information: level of general knowledge. Comprehension: ability to understand questions and grasp concepts. Arithmetic: capacity to grasp and employ mathematical concepts. Similarities: ability to employ abstract thought. Digit Span: tasks designed to measure attention span. Vocabulary: grasp of the meaning of words. The Performance Scale: Each of the following tests is a set of tasks designed to assess a different area. Brun_0471443956_4p_10_r1.qxd 6/27/02 1:46 PM Page 143 Intelligence: In Pursuit of Rational Thought and Effective Action 143 Digit Symbol: mental flexibility and ability to employ arbitrary symbols. Picture Completion: ability to detect the missing parts of an organized whole (i.e., a Gestalt). Block Design: ability to relate a printed pattern to a physical construction. Picture Arrangement: ability to comprehend the “before and after” aspect of time. Also useful in evaluating the subject’s level of social intelligence. Object Assembly: ability to place parts in a correct relationship to a whole. Under optimal conditions, a trained psychologist administers the Wechsler Adult Intelligence Scale to a given to a subject on an individual basis. The results of the test, when properly scored and evaluated, provide a clear picture of the individual’s level of cognitive functioning at both a general level and at the level of specific mental abilities. (a) The Wechsler Adult Intelligence Scale consists of a set of how many subtests? (b) What subtest in the Verbal Scale is designed to assess the subject’s ability to understand questions and grasp concepts? (c) What subtest in the Verbal Scale is designed to assess the subject’s grasp of the meaning of words? (d) What subtest in the Performance Scale is designed to assess the subject’s mental flexibility and ability to employ arbitrary symbols? (e) What subtest in the Performance Scale is designed to assess the subject’s ability to relate a printed pattern to a physical construction? Answers: (a) Eleven; (b) Comprehension; (c) Vocabulary; (d) Digit Symbol; (e) Block Design. The Concept of an Intelligence Quotient: Following the Bell-Shaped Curve As already noted, the concept of mental age (MA) is of limited value because it is unstable. As one’s chronological age (CA) increases, so does one’s mental age. Consequently, a German psychologist named William Stern suggested that a ratio based on the comparison of mental age with chronological age would tend to be relatively stable. Stern proposed the following formula: MA IQ = ᎏᎏ × 100 CA IQ stands for intelligence quotient. The IQ is a quotient because it is the result of a division process.