intelligence

(ĭn-tĕl'ə-jəns)
n.

1. 1. The capacity to acquire and apply knowledge.
   2. The faculty of thought and reason.
   3. Superior powers of mind. See synonyms at mind.
2. An intelligent, incorporeal being, especially an angel.
3. Information; news. See synonyms at news.
4. 1. Secret information, especially about an actual or potential enemy.
   2. An agency, staff, or office employed in gathering such information.
   3. Espionage agents, organizations, and activities considered as a group: "Intelligence is nothing if not an institutionalized black market in perishable commodities" (John le Carré).

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General mental ability due to the integrative and adaptive functions of the brain that permit complex, unstereotyped, purposive responses to novel or changing situations, involving discrimination, generalization, learning, concept formation, inference, mental manipulation of memories, images, words and abstract symbols, eduction of relations and correlates, reasoning, and problem solving.

Intelligence tests are diverse collections of tasks (or items), graded in difficulty. The person's performance on each item can be objectively scored (for example, pass or fail); the total number of items passed is called the raw score. Raw scores are converted to some form of scaled scores which can be given a statistical interpretation.

The first practical intelligence test for children, devised in 1905 by the French psychologist Alfred Binet, converted raw scores to a scale of “mental age,” defined as the raw score obtained by the average of all children of a given age. Mental age (MA) divided by chronological age (CA) yields the well known intelligence quotient or IQ. When multipled by 100 (to get rid of the decimal), the average IQ at every age is therefore 100, with a standard deviation of approximately 15 or 16. Because raw scores on mental tests increase linearly with age only up to about 16 years, the conversion of raw scores to a mental-age scale beyond age 16 must resort to statistical artifices. Because of this problem and the difficulty of constructing mental-age scales which preserve exactly the same standard deviation of IQs at every age, all modern tests have abandoned the mental-age concept and the calculation of IQ from the ratio of MA to CA. Nowadays the IQ is simply a standardized score with a population mean of 100 and a standard deviation (σ) of 15 at every age from early childhood into adulthood. The middle 50%, considered “average,” fall between IQs of 90 and 110. IQs below 70 generally indicate “mental retardation,” and above 130, “giftedness.”

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(1) Having processing capability. In this context, every computer is "intelligent;" however, that is often not the case with the software! See smart.

(2) Information. See DOD intelligence glossary.

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Although there is no universally accepted definition of intelligence, it is generally regarded as an ability to act purposefully, to think rationally, and to deal effectively with new situations. There have been many attempts to measure intelligence, the best known being the standardized test which scores an individual's intelligence quotient (IQ). An IQ is the ratio of mental age to actual age (usually expressed as a percentage). It is often used as an index of intellectual development.

In recent years much research has been conducted on the possible influence of vitamins and minerals on intelligence. It has been claimed that vitamin supplementation can significantly improve a child's learning ability. It is generally accepted that vitamin and mineral deficiencies may retard intellectual development (e.g. iron-deficient children have reduced verbal ability, perform poorly in IQ tests, and have lower powers of concentration). However, the claim that supplements can increase the intelligence of children who show no clinical signs of vitamin or mineral deficiency, are hotly disputed. Until we are all able to agree on a definition of intelligence and on a universally accepted means of testing it, the controversy will continue.

What is intelligence? Ability to learn? Success in adapting to new situations? The number and originality of mental associations? Skill in reasoning or producing abstract ideas or problem-solving? All of these definitions have been proposed but none has yet become definitive, either for professional psychologists or for the lay public. In general, intelligence most often refers to practical problem-solving ability, verbal ability, social competence, and effective adaptation to one's environment and to new situations and changes within it. There is often a quantitative dimension as well: some individual or group or species has more or less of it than some other. Cross-cultural studies have revealed significant differences in the ways in which various groups define the sets of characteristics associated with something like overall mental ability. And historically, even in the West, intelligence has meant a number of things. It was used most often until the twentieth century to refer simply to all the intellective functions of the mind, as distinguished from the will and the emotions, universal human properties little associated with measurable individual ability.

Francis Galton in England and Alfred Binet in France were among the most significant within psychology in developing the modern conception of intelligence. Beginning in the 1860s, Galton pursued a programme of investigating individual differences in mental ability by measuring reactions to various physical stimuli and then showing that those measurements were distributed, like height or weight, according to the normal or bell-shaped curve. Although Galton's anthropometric approach was soon abandoned, his insistence that intelligence was a biological entity that was inheritable, and normally distributed in populations, persisted, and became linked to a very different method of assessing intelligence devised by Binet. In response to a governmental education commission, Binet and his colleague Théodore Simon created a set of tests, individually administered, which were designed to track normal intellectual progress. Oriented toward the higher mental processes, the Binet-Simon Intelligence Scale (1905, 1908, 1911) was able to produce a number, the mental age (MA), that characterized the intellectual level of each child administered the examination. Not only did it allow test-takers to be ranked according to the level of their intelligence, but it suggested that intelligence itself was a discrete and measurable entity.

The Binet-Simon Intelligence Scale set the standard for all further developments in the field. Lews M. Terman's 1916 revision of the Binet-Simon scale, the Stanford-Binet, quickly became the benchmark instrument for the assessment of intelligence, and helped to introduce the concept of the intelligence quotient (IQ), a ratio of mental age to chronological age which was adopted from German psychologist Wilhelm Stern and designed to produce a measure of intelligence which was constant over time. Revised in 1937 and again in 1960, the Stanford-Binet has remained one of the pre-eminent individual measures of intelligence. Its main rivals have been the tests of child (WISC) and adult (WAIS) intelligence developed by David Wechsler, starting in the 1940s, which provide, in addition to an overall measure of IQ, individual assessments of verbal and non-verbal ability.

Wechsler's provision of two additional scores highlights one of the persistent theoretical issues pursued in studies of intelligence: whether it is one thing or many. Using factor analysis, British psychologist Charles Spearman (1904) argued that performance on intelligence tests could be explained on the basis of two factors, general intelligence (g) and task-specific abilities (s). Spearman's theory was challenged during the 1920s and 1930s, by L. L. Thurstone in the US and Godfrey Thomson in the UK, both of whom also employed factor analysis, but who used it to argue against g and in favour of the existence of a small number of relatively independent abilities. During the post-war period, Philip E. Vernon, among others, attempted to arbitrate between these competing theories using a hierarchical conception of intelligence, which depicted intelligence as extending from a single overall ability down to a large number of specific skills. This approach was rejected by Joy P. Guilford, however, who proposed instead a three-dimensional model that initially posited 120 independent mental factors and subsequently posited 150. Commencing in the 1970s, various cognitively-based models have been put forward, including most prominently those by Howard Gardner, with his seven discrete types of intelligence, and Robert J. Sternberg, with his triarchic theory of intelligence. These cognitive approaches owe a great deal to the influence of the psychometric tradition and also to developmental studies of intelligence, particularly those associated with Jean Piaget (stages of intellectual development) and Lev Vygotsky (social influences on intellectual development).

The second major theoretical issue in intelligence studies has been over the relative weights of nature and nurture. Galton's work on individual intelligence began with the assumption that intelligence was both biological and inheritable, a belief that ran strong during the heyday of eugenics (1900s-20s), and was used to support such programs as immigration restriction and sterilization of the mentally deficient. Research during the 1930s and 1940s, however, especially at the Iowa Child Welfare Research Station, emphasized the importance of nurture: IQ, for example, was found to change when children were placed in different environments. After the war, studies continued to show the powerful effects of both nature and nurture on IQ. Research on identical twins has led some psychologists to conclude that at least 60% of IQ results from heredity. At the same time, a great deal of data has been collected indicating the influence of nutrition, kind of education received, and degree of sensory stimulation on IQ score.

The enormous professional interest in intelligence has been sustained by its many practical applications. As part of mobilization for World War I, American psychologists created new instruments that could be group administered, and tested approximately 1.75 million army recruits. This programme served to introduce the nation to standardized intelligence testing, and during the 1920s intelligence testing boomed, adopted by schools and industry as a means of efficient placement and assessment of students and personnel. Although some of the infatuation with testing receded by the end of the decade, intelligence and its measurement had by then become permanent features of the social and intellectual landscape. Debates over the provision of educational opportunities, the capabilities of various ethnic or racial groups, and the value of affirmative action have all been conducted at least in part through the language of native intelligence. However ill-defined, intelligence has become a concept of much consequence within the contemporary world.

— John Carson

Bibliography

• Ceci, S. J. (1996). On intelligence: a bioecological treatise on intellectual development. Harvard University Press, Cambridge, MA.
• Sokal, M. M. (ed.) (1987). Psychological testing and American society, 1890-1930. Rutgers University Press, New Brunswick

noun

1. The faculty of thinking, reasoning, and acquiring and applying knowledge: brain (often used in plural), brainpower, intellect, mentality, mind, sense, understanding, wit. Slang smart (used in plural). See ability/inability, thoughts.
2. That which is known about a specific subject or situation: data, fact (used in plural), information, knowledge, lore. See knowledge/ignorance.
3. New information, especially about recent events and happenings: advice (often used in plural), news, tiding (often used in plural), word. Informal scoop. See knowledge/ignorance, words.

n

Definition: ability to perceive, understand
Antonyms: ignorance, inability, ineptness

n

Definition: perception
Antonyms: stupidity

Definition

Intelligence is an abstract concept whose definition continually evolves and often depends upon current social values as much as scientific ideas. Modern definitions refer to a variety of mental capabilities, including the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience, as well as the potential to do these things.

Description

Several theories about intelligence emerged in the twentieth century and with them debate about the nature of intelligence and whether it determined by hereditary factors, the environment, or both. As methods developed to assess intelligence, experts theorized about the measurability of intelligence, its accuracy, and the field known as psychometrics, a branch of psychology dealing with the measurement of mental traits, capacities, and processes. Publication in 1994 of The Bell Curve: Intelligence and Class Structure in American Life by Richard J. Herrnstein and Charles Murray stirred the controversy. Their findings pointed to links between social class, race, and intelligence quotient (IQ) scores, despite questions by many about the validity of IQ tests as a measurement of intelligence or a predictor of achievement and success.

Part of the problem regarding intelligence stems from the fact that nobody has adequately defined what intelligence really means. In everyday life, people have a general understanding that some people are "smart," but when they try to define "smart" precisely, they often have difficulty because a person can be gifted in one area and average or below in another. To explain this phenomenon, some psychologists have developed theories to include multiple components of intelligence.

Since about 1970, psychologists have expanded the notion of what constitutes intelligence. Newer definitions of intelligence encompass more diverse aspects of thought and reasoning. For example, American psychologist Robert Sternberg developed a three-part theory of intelligence which states that behaviors must be viewed within the context of a particular culture; that a person's experiences impact the expression of intelligence; and that certain cognitive processes control all intelligent behavior. When all these aspects of intelligence are viewed together, the importance of how people use their intelligence becomes more important than the question of "how much" intelligence a person has. Sternberg has suggested that some intelligence tests focus too much on what a person has already learned rather than on how well a person acquires new skills or knowledge.

Another multifaceted approach to intelligence is Howard Gardner's proposal that people have eight intelligences:

• Musical: Children with musical intelligence are always singing or tapping out a beat. They are aware of sounds others miss. Musical children are discriminating listeners.
• Linguistic: Children with linguistic intelligence excel at reading, writing, telling stories, and doing crossword or other word puzzles.
• Logical-Mathematical: Children with this type of intelligence are interested in patterns, categories, and relationships. They are good at mathematic problems, science, strategy games, and experiments.
• Bodily-Kinesthetic: These children process knowledge through their senses. They usually excel at athletics and sports, dance, and crafts.
• Spatial: These children think in images and pictures. They are generally good at mazes and jigsaw puzzles. They often spend lots of time drawing, building (with blocks, Legos, or erector sets), and daydreaming.
• Interpersonal: This type of intelligence fosters children who are leaders among their peers, are good communicators, and understand the feelings and motives of others.
• Intrapersonal: These children are shy, very aware of their own feelings, and are self-motivated.
• Naturalist: This type of intelligence allows children to distinguish among, classify, and use features of the environment. These children are likely to make good farmers, gardeners, botanists, geologists, florists, and archaeologists. Naturalist adolescents can often name and describe the features of every make of car around them.

Intelligence Tests

There are many different types of intelligence tests, and they all do not measure the same abilities. Although the tests often have aspects that are related with each other, one should not expect that scores from one intelligence test that measures a single factor will be similar to scores on another intelligence test that measures a variety of factors. Many people are under the false assumption that intelligence tests measure a person's inborn or biological intelligence. Intelligence tests are based on an individual's interaction with the environment and never exclusively measure inborn intelligence. Intelligence tests have been associated with categorizing and stereotyping people. Additionally, knowledge of one's performance on an intelligence test may affect a person's aspirations and motivation to obtain goals. Intelligence tests can be culturally biased against certain groups.

STANFORD-BINET INTELLIGENCE SCALES. Consisting of questions and short tasks arranged from easy to difficult, the Stanford-Binet measures a wide variety of verbal and nonverbal skills. Its fifteen tests are divided into the following four cognitive areas: verbal reasoning (vocabulary, comprehension, absurdities, verbal relations); quantitative reasoning (math, number series, equation building); abstract/visual reasoning (pattern analysis, matrices, paper folding and cutting, copying); and short-term memory (memory for sentences, digits, and objects, and bead memory). A formula is used to arrive at the intelligence quotient, or IQ. An IQ of 100 means that the child's chronological and mental ages match. Traditionally, IQ scores of 90–109 are considered average; scores below 70 indicate mental retardation. Gifted children achieve scores of 140 or above. Revised in 1986, the Stanford-Binet intelligence test can be used with children starting at age two. The test is widely used to assess cognitive development and often to determine placement in special education classes.

WECHSLER INTELLIGENCE SCALES. The Wechsler intelligence scales are divided into two sections: verbal and nonverbal, with separate scores for each. Verbal intelligence, the component most often associated with academic success, implies the ability to think in abstract terms using either words or mathematical symbols. Performance intelligence suggests the ability to perceive relationships and fit separate parts together logically into a whole. The inclusion of the performance section in the Wechsler scales is especially helpful in assessing the cognitive ability of children with speech and language disorders or whose first language is not English. The test can be of particular value to school psychologists screening for specific learning disabilities because of the number of specific subtests that make up each section.

KAUFMAN ASSESSMENT BATTERY FOR CHILDREN. The Kaufman Assessment Battery for Children (KABC) is an intelligence and achievement test for children ages 2.5–12.5 years. It consists of 16 subtests, not all of which are used for every age group. A distinctive feature of the KABC is that it defines intelligence as problem-solving ability rather than knowledge of facts, which it considers achievement. This distinction is evident in the test's division into two parts—intelligence and achievement—which are scored separately and together. The test's strong emphasis on memory and lesser attention to verbal expression are intended to offset cultural disparities between black and white children. In addition, the test may be given to non-native speakers in their first language and to hearing impaired children using American Sign Language.

Infancy

Babies were once thought to enter the world with minds that were blank slates that developed through a lifetime of experiences. It is as of the early 2000s known that newborns have brains as sophisticated as the most powerful supercomputers, pre-wired with a large capacity for learning and knowledge. In the first few months of life, a baby's brain develops at an amazing rate. At birth, infants have the senses of sight, sound, and touch. At about three or four months, infants begin to develop memory, and it expands quickly. Modern brain imaging techniques have confirmed that children's intelligence is not just hereditary but is also affected greatly by environment. Babies' brains develop faster during their first year than at any other time. By three months, babies can follow moving objects with their eyes, are extremely interested in their surroundings, and can recognize familiar sounds, especially their parents' voices. At six months, infants begin to remember familiar objects, react to unfamiliar people or situations, and realize that objects are permanent. At seven months, babies can recognize their own name. Parents can help their infants develop their intelligence by talking and reading to them, playing with them, and encouraging them to play with a variety of age-appropriate toys.

Toddlerhood

Toddlers' lives generally revolve around experimenting with and exploring the environment around them. The primary source of learning for toddlers is their families. During their third year, toddlers should be able to sort and group similar objects by their appearance, shape, and function. They also start to understand how some things work, and their memory continues to improve rapidly. They are able to remember and seek out objects that are hidden or moved to a different location. Toddlers should be able to follow two-step instructions and understand contrasting ideas, such as large and small, inside and outside, opened and closed, and more and less. Toddlers also develop a basic understanding of time in relation to their regular activities, such as meals and bedtime.

Preschool

At age three, preschoolers can say short sentences, have a vocabulary of about 900 words, show great growth in communication, tell simple stories, use words as tools of thought, want to understand their environment, and answer questions. At age four, children can use complete sentences, have a 1,500-word vocabulary, frequently ask questions, and learn to generalize. They are highly imaginative, dramatic, and can draw recognizable simple objects. Preschoolers also should be able to understand basics concepts such as size, numbers, days of the week, and time. They should have an attention span of at least 20 minutes. Children this age are still learning the difference between reality and fantasy. Their curiosity about themselves and the world around them continues to increase.

School Age

At age five, children should have a vocabulary of more than 2,000 words. They should be able to tell long stories, carry out directions well, read their own name, count to ten, ask the meaning of words, know colors, begin to know the difference between fact and fiction, and become interested in their surrounding environment, neighborhood, and community. Between the ages of seven and 12, children begin to reason logically and organize their thoughts coherently. However, generally, they can only think about actual physical objects; they cannot handle abstract reasoning. They also begin to lose their self-centered way of thinking. During this age range, children can master most types of conservation experiments and begin to understand that some things can be changed or undone. Early school-age children can coordinate two dimensions of an object simultaneously, arrange structures in sequence, change places or reverse the normal order of items in a series, and take something such as a story, incident, or play out of its usual setting or time and relocate it in another.

Starting at about age 12, adolescents can formulate hypotheses and systematically test them to arrive at an answer to a problem. For example, they can formulate hypotheses based on the phrase "what if." They can think abstractly and understand the form or structure of a mathematical problem. Another characteristic of the later school-age years is the ability to reason contrary to fact. That is, if they are given a statement and asked to use it as the basis of an argument, they are capable of accomplishing the task. Until they reach the age of 15 or 16, adolescents are generally not capable of reasoning as an adult. High school-age adolescents continue to gain cognitive and study skills. They can adapt language to different contexts, master abstract thinking, explore and prepare for future careers and roles, set goals based on feelings of personal needs and priorities, and are likely to reject goals set by others.

Common Problems

Autism

Autism is a profound mental disorder marked by an inability to communicate and interact with others. The condition's characteristics include language abnormalities, restricted and repetitive interests, and the appearance of these characteristics in early childhood. As many as two-thirds of children with autistic symptoms are mentally deficient. However, individuals with autism can also be highly intelligent. Autistic individuals typically are limited in their ability to communicate nonverbally and verbally. About half of all autistic people never learn to speak. They are likely to fail in developing social relationships with peers, have limited ability to initiate conversation if they do learn how to talk, and show a need for routine and ritual. Various abnormalities in the autistic brain have been documented. These include variations in the frontal lobes of the brain that focus on control and planning and in the limbic system, a group of structures in the brain that are linked to emotion, behavior, smell, and other functions. Autistic individuals may suffer from a limited development of the limbic system. This would explain some of the difficulties faced by autistic individuals in processing information.

Mental Retardation

Mental retardation usually refers to people with an IQ below 70. According to the American Psychiatric Association, a mentally retarded person is significantly limited in at least two of the following areas: self-care, communication, home living, social-interpersonal skills, self-direction, use of community resources, functional academic skills, work, leisure, health, and safety. Mental retardation affects roughly 1 percent of the U.S. population. According to the U.S. Department of Education, about 11 percent of school-aged children were enrolled in special education programs for students with mental retardation. There are four categories of mental retardation: mild, moderate, severe, and profound. There are many different causes of mental retardation, both biological and environmental. In about 5 percent of cases, retardation is transmitted genetically, usually through abnormalities in chromosomes, such as Down syndrome or fragile X syndrome. Children with Down syndrome have both mental and motor retardation. Most are severely retarded, with IQs between 20 and 49. Fragile X syndrome, in which a segment of the chromosome that determines gender is abnormal, primarily affects males.

Parental Concerns

Autism symptoms begins in infancy, but typically the condition is diagnosed between the ages of two to five. The symptoms of mental retardation are usually evident by a child's first or second year. In the case of Down syndrome, which involves distinctive physical characteristics, a diagnosis can usually be made shortly after birth. Mentally retarded children lag behind their peers in developmental milestones such as sitting up, smiling, walking, and talking. They often demonstrate lower than normal levels of interest in their environment and less responsiveness to others, and they are slower than other children in reacting to visual or auditory stimulation. By the time a child reaches the age of two or three, retardation can be determined using physical and psychological tests. Testing is important at this age if a child shows signs of possible retardation because alternate causes, such as impaired hearing, may be found and treated. There is no cure for autism or mental retardation.

When to Call the Doctor

Parents should consult a healthcare professional if their child's intellectual development appears to be significantly slower than their peers. Children suspected of having intelligence development problems should undergo a comprehensive evaluation to identify their difficulties as well as their strengths. Since no specialist has all the necessary skills, many professionals might be involved. General medical tests as well as tests in areas such as neurology (the nervous system), psychology, psychiatry, special education, hearing, speech and vision, and physical therapy may be needed. A pediatrician or a child and adolescent psychiatrist often coordinates these tests.

Parents should pay close attention to possible symptoms in their children. Autism is diagnosed by observing the child's behavior, communication skills, and social interactions. Medical tests should rule out other possible causes of autistic symptoms. Criteria that mental health experts use to diagnose autism include problems developing friendships, problems with make-believe or social play, endless repetition of words or phrases, difficulty in carrying on a conversation, obsessions with rituals or restricted patterns, and preoccupation with parts of objects. A diagnosis of mental retardation is made if an individual has an intellectual functioning level well below average and significant limitations in two or more adaptive skill areas. If mental retardation is suspected, a comprehensive physical examination and medical history should be done immediately to discover any organic cause of symptoms. If a neurological cause such as brain injury is suspected, the child may be referred to a neurologist or neuropsychologist for testing.

Resources

Books

Armstrong, Thomas, and Jennifer Brannen. You're Smarter than You Think: A Kid's Guide to Multiple Intelligences. Minneapolis, MN: Free Spirit Publishing, 2002.

Brill, Marlene Targ. Raising Smart Kids for Dummies. New York: Wiley Publishing, 2003.

Deary, Ian J. Intelligence: A Very Short Introduction. Oxford, UK: Oxford University Press, 2001.

Georgas, James, et al. Culture and Children's Intelligence: Cross-Cultural Analysis of the WISC-III. Burlington, MA: Academic Press, 2003.

Periodicals

Bailey, Ronald. "The Battle for Your Brain: Science Is Developing Ways to Boost Intelligence, Expand Memory, and More. But Will You be Allowed to Change Your Own Mind?" Reason (February 2003): 25–31.

Bower, Bruce. "Essence of G: Scientists Search for the Biology of Smarts-General Factor Used to Determine Intelligence Level." Science News (February 8, 2003): 92–3.

Furnham, Adrian, et al. "Parents Think Their Sons Are Brighter than Their Daughters: Sex Differences in Parental Self-Estimations and Estimations of their Children's Multiple Intelligences." Journal of Genetic Psychology (March 2002): 24–39.

Gottfredson, Linda S. "Schools and the G Factor." The Wilson Quarterly (Summer 2004): 35–45.

Stanford, Pokey. "Multiple Intelligences for Every Classroom." Intervention in School & Clinic (November 2003): 80–85.

Organizations

Child Development Institute. 3528 E Ridgeway Road Orange, CA 92867. Web site: www.cdipage.com.

National Academy of Child & Adolescent Psychiatry. 3615 Wisconsin Ave. NW, Washington, DC 20016. Web site: www.aacap.org.

Web Sites

Rosenblum, Gail. "Baby Brainpower." Sesame Workshop, 2004. Available online at www.sesameworkshop.org/babyworkshop/library/article.php?contentId=860 (accessed November 10, 2004).

"The Theory of Multiple Intelligences." Human Intelligence, Fall 2001. Available online at www.indiana.edu/~intell/mitheory.shtml (accessed November 10, 2004).

[Article by: Ken R. Wells]

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The roles of genes and environment in the determination of intelligence have been controversial for more than 100 years. Studies of the question have often been marred by untested assumptions, poor design, and even racism, faults that more modern studies have striven to avoid. Nonetheless, examining the biology of intelligence is an enterprise that continues to be fraught with difficulty, and there remains no real consensus even on how to define the term.

Iq Tests

Conventional measures of intelligence are obtained using standard tests, called intelligence quotient tests or, more commonly, IQ tests. These tests have been shown to be reliable and valid. Reliability means that they measure the same thing from person to person, whereas validity means that they measure what they claim to measure. IQ tests measure a person's ability to reason and to solve problems. These abilities are frequently called general cognitive ability, or "g."

Almost all genetic studies of the heritability of intelligence (how much is due to genetics and how much is due to the environment) have been obtained from IQ tests. To understand the studies, therefore, it is important to understand what IQ tests measure, and how their use and interpretation have changed over time.

The standard IQ-measurement approach to intelligence is among the oldest of approaches and probably began in 1876, when Francis Galton investigated how much the similarity between twins changed as they developed over time. Galton's study was concerned with measuring psychophysical abilities, such as strength of handgrip or visual acuity. The concept of general cognitive ability was first described by Charles Spearman in 1904. Later, Alfred Binet and Theophile Simon (1916) evaluated intelligence based on judgment, involving adaptation to the environment, direction of one's efforts, and self-criticism.

Most standard test results now include three scores: VIQ, PIQ, and FSIQ. The VIQ score measures verbal ability (verbal IQ), PIQ measures performance ability (performance IQ), and FSIQ provides an overall measurement (full scale IQ). Commonly used IQ tests include the Stanford-Binet Intelligence Scale, the Wechsler Intelligence Scale for Children (WISC), and the Wechsler Adult Intelligence Scales. The results achieved by individual testtakers on one of these IQ tests are likely to be similar to the results they achieve on the others, and they all aim to measure general cognitive ability (among other things). Measures of scholastic achievement, such as the SAT and the ACT correlate highly with "g."

Environmental Effects on Intelligence

The study of intelligence must take environmental effects into account. The Flynn effect describes a phenomenon that indicates that IQ has increased about 3 points per decade over the last fifty years, with children scoring higher than parents in each generation. This increase has been linked to multiple environmental factors, including better nutrition, increased schooling, higher educational attainment of parents, less childhood disease, more complex environmental stimulation, lower birth rates, and a variety of other factors.

Males and females have equivalent "g" scores. The question of racial differences and IQ arose when a 10 point IQ difference between African Americans and Americans of European descent was documented. Two adoption studies indicate that the effect may be in part related to environment factors, including culture. Also, environmental differences similar to those identified with the Flynn effect can be postulated. Studies of black Caribbean children and English children raised in an orphanage in England found that the black Caribbean children had higher IQs than the English children, with mixed racial children in between. A study comparing black children adopted by white families and those who were adopted into black families in the United States showed that black children raised by whites had higher IQ scores, again suggesting that the environment played a role.

Expanded Concepts of Intelligence

Many of the standard measures of IQ, such as the WISC and the Stanford-Binet, have changed their content over the years. Although they both still report verbal, performance, and total scores, the Wechsler model now offers scores for four additional factors (verbal comprehension, perceptual organization, processing speed, and freedom from distractibility). The Stanford-Binet also yields additional scores, including abstract-visual reasoning, quantitative reasoning, and short-term memory.

However, the majority of research into genetic and environmental variance in IQ has centered on the assumption that general cognitive ability is the essence of intelligence. Newer tests that measure specific abilities have not been included in genetic studies. These include, for example, tests that measure creativity in a model for intelligence. The addition of new factors in the Wechsler and Stanford-Binet IQ tests represents a trend toward a broader approach to IQ, and away from the notion that IQ can be understood by the single factor, "g."

Family, Twin, and Adoption Studies

Genetic studies have traditionally used models that evaluate how much of the variability in IQ is due to genes and how much is associated with environment. These studies include family studies, twin studies, and adoption studies.

General cognitive ability runs in families. For first-degree relatives (parents, children, brothers, sisters) living together, correlations of "g" for over 8,000 parent-offspring pairs averaged 0.43 (0.0 is no correlation, 1.0 is complete correlation). For more than 25,000 sibling pairs, "g" correlations averaged 0.47. Heritability estimates range from 40 to 80 percent, meaning that 40 to 80 percent of "g" is due to genes.

In twin studies of over 10,000 pairs of twins, monozygotic (genetically identical) twins averaged an 0.85 correlation of "g," whereas for dizygotic (fraternal, like brothers or sisters) same-sex twins the "g" correlations were 0.60. These twin studies suggest that the heritability (genetic effect) accounts for about half of the variance in "g" scores.

Adoption studies also provide evidence for substantial heritability of "g." The "g" estimate for identical twins raised apart is similar to that of identical twins raised together, proving that for genetically identical individuals, environmental differences did not affect "g." The Colorado Adoption Study (CAP) of first-degree relatives who were adopted also indicated significant heritability of "g." Thus, classical genetic studies indicate that there is a statistically significant and substantial genetic influence on "g."

Newer genetic research on general cognitive ability has focused on developmental changes in IQ, multivariate relations (contributions of multiple factors) among cognitive abilities, and specific genes responsible for the heritability of "g." Developmental changes over time were first studied by Galton in 1876. The CAP study was conducted over twenty-five years and evaluated 245 children who had been separated from their parents at birth and adopted by one month of age. This study, and others, showed that the variance in "g" due to environment for an adopted child in his or her adoptive family is largely unconnected with the shared adoptive family upbringing, that is, a shared parent-sibling environment. For adoptive parents and their adopted children, the parent-offspring correlations for heritability were around zero. For adopted children and their biologic mothers or for children raised with their biologic parents, heritability was the same, increasing with age.

Recent studies indicate that heritability increases over time, with infant measures of about 20 percent, childhood measures at 40 percent, and adult measures reaching 60 percent. Why is there an age effect for the heritability of "g"? Part of this could be due to different genes being expressed over time, as the brain develops. The stability of the heritability measure correlates with changes in brain development, with "maturity" of brain structure achieved after adolescence. Also, it is likely that small gene effects early in life become larger as children and adolescents select or create environments that foster their strengths.

Multivariate relations among cognitive abilities affect more than general cognitive ability as measured by "g." Current models of cognitive abilities include specific components such as spatial and verbal abilities, speed of processing, and memory abilities. Less is known about the heritabilities of these specific cognitive skills. They also show substantial genetic influence, although this influence is less than what has been found for "g." Multivariate genetic analyses indicate that the same genetic factors influence different abilities. In other words, a specific gene found to be associated with verbal ability may also be associated with spatial ability and other specific cognitive abilities. Four studies have shown that genetic effects on measures of school achievement are highly correlated with genetic effects on "g." Also, discrepancies between school achievement and "g," as occurs with under-achievers, are predominantly of environmental origin.

Genes for Intelligence

The search for specific genes associated with IQ is proceeding at a rapid pace with the completion of the Human Genome Project. While defects in single genes, such as the fragile X gene, can cause mental retardation, the heritability of general cognitive ability is most likely due to multiple genes of small effect (called quantitative trait loci, or QTLs) rather than a single gene of large effect. QTLs contribute additively and interchangeably to intelligence.

Genetic studies have identified QTLs associated with "g" on chromosomes 4 and 6. These studies involved both children with high "g" and children with average "g." QTLs on chromosome 6 have been identified and shown to be active in the regions of the brain involved in learning and memory. The gene identified is for insulin-like growth factor 2 receptor, or IGF2R, the exact function of which is still unknown. One allele (alternative form) of IGR2R was found to be present 30 percent of the time in two groups of children with high "g." This was twice the frequency of its occurrence in two groups of children with average "g," and these findings have been successfully replicated in other studies. QTLs associated with "g" have also been identified on chromosome 4. Future identification of QTLs will allow geneticists to begin to answer questions about IQ and development and gene-environment interaction directly, rather than relying on less specific family, adoption, and twin studies.

In summary, intelligence measurements ranging from specific cognitive abilities to "g" have a complex relationship. Genetic contributions are large, and heritability increases with age. Heritability remains high for verbal abilities during adulthood. Finally, the identification of QTLs associated with "g" and with specific cognitive abilities is just beginning.

Bibliography

Casse, D. "IQ since 'The Bell Curve.'" Commentary Magazine 106, no. 2 (1998): 33-41.

Chiacchia, K. B. "Race and Intelligence." In Encyclopedia of Psychology, 2nd ed., Bonnie Strickland, ed. Farmington Hills, MI: Gale Group, 2001.

Deary, I. J. "Differences in Mental Ability." British Medical Journal 317 (1998): 1701-1703.

Fuller, J. L., and W. R. Thompson. "Cognitive and Intellectual Abilities." In Foundations of Behavior Genetics. St. Louis, MO: C.V. Mosby Co., 1978.

Plomin, R. "Genetics of Childhood Disorders, III: Genetics and Intelligence." Journal of the American Academy of Childhood and Adolescent Psychiatry 38 (1999): 786-788.

Sternberg, R. J., and J. C. Kaufman. "Human Abilities." Annual Review Psychology 49: 479-502.

Sternberg, R. J., and E. L. Grigorenko. "Genetics of Childhood Disorders, I: Genetics and Intelligence." Journal of the American Academy of Childhood and Adolescent Psychiatry 38 (1999): 486-488.

—Harry Wright and Ruth Abramson

Most generally, the capacity to deal flexibly and effectively with practical and theoretical problems. Since peoples' capacities to do this vary with the problem, it may be doubted whether there is a useful level of abstraction at which one thing, intelligence, can be thought of as equally manifested in whatever logical, theoretical, practical, mathematical, linguistic, etc. successes we achieve. Nor is there much confidence left that intelligence tests measure any such general capacity, as opposed to measuring the subject's capacity to take intelligence tests, often of very specific and culturally peculiar kinds. For the question whether humans alone possess intelligence, see animal thought, instinct.

There is no universally accepted definition of intelligence, but it is generally regarded as an ability to act purposefully, to think rationally, and to deal effectively with the environment; it is often measured by an intelligence test. A person of high intelligence has the ability to adapt to new situations that often involves the ability to utilize abstract concepts and to learn to grasp novel relationships. See also sport intelligence.

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This entry consists of the following articles:

• Intelligence: Emotional Intelligence
• Intelligence: Measurement
• Intelligence: A Continuing Field of Debate
• Intelligence: Multiple Intelligences
• Intelligence: Myths, Mysteries, and Realities

Innumerable tests are available for measuring intelligence (see intelligence: measurement), yet no one is quite certain of what intelligence is, or even of just what it is that the available tests are measuring. There have been any number of attempts to resolve these uncertainties, attempts that have differed in their approach to the problem, and in the outcome of applying each given approach.

One time-honoured approach to discovering the meaning of a construct is to seek expert opinion regarding its definition. This is exactly what the editors of a major psychological journal did in 1921, when they sought the opinions of experts in the field of intelligence regarding what they 'conceive "intelligence" to be, and by what means it can best be measured by group tests' (Intelligence and its Measurement, 1921, p. 123). Fourteen experts replied, with definitions of intelligence such as the following: (i) the power of good responses from the point of view of truth or fact (E. L. Thorndike); (ii) the ability to carry on abstract thinking (L. M. Terman); (iii) having learned or having the ability to learn to adjust oneself to the environment (S. S. Colvin); (iv) the ability to adapt oneself adequately to relatively new situations in life (R. Pintner); (v) the capacity for knowledge, and knowledge possessed (V. A. C. Henmon); (vi) a biological mechanism by which the effects of a complexity of stimuli are brought together and given a somewhat unified effect in behaviour (J. Peterson); (vii) the capacity to inhibit an instinctive adjustment, the capacity to redefine the inhibited instinctive adjustment in the light of imaginally experienced trial and error, and the volitional capacity to realize the modified instinctive adjustment into overt behaviour to the advantage of the individual as a social animal (L. L. Thurstone); (viii) the capacity to acquire capacity (H. Woodrow); and (ix) the capacity to learn or to profit by experience (W. F. Dearborn). The other experts did not answer the question directly.

Viewed narrowly, there seem to be almost as many definitions of intelligence as there were experts asked to define it. Viewed broadly, however, two themes seem to run through at least several of these definitions: the capacity to learn from experience and adaptation to one's environment. Indeed, an earlier definition often cited by these experts viewed intelligence as general adaptability to new problems and conditions of life. (For an update of the 1921 symposium, see Sternberg and Detterman 1986.)

If one is dissatisfied with the heterogeneity in these definitions, one can attempt to answer the question of what intelligence is by begging the question. Edwin Boring (1923) did just that when he defined intelligence as whatever it is that the tests measure. This definition tells us no more than we knew when we started, and it may tell us less: no two tests measure exactly the same thing, so that one is left with as many definitions of intelligence as there are tests (which is certainly a number greater even than that of experts in the field!).

A more recent and sophisticated version of the definitional approach to discovering what intelligence is has been suggested by Ulric Neisser (1979). According to Neisser, the concept of intelligence is organized around a 'prototype', or ideal case. One is intelligent to the extent that one resembles this ideal case:

There are no definitive criteria of intelligence, just as there are none for chairness; it is a fuzzy-edged concept to which many features are relevant. Two people may both be quite intelligent and yet have very few traits in common — they resemble the prototype along different dimensions. ... [Intelligence] is a resemblance between two individuals, one real and the other prototypical. (p. 185)

If there is a single prototype, or ideal case, Neisser's notion will give us a concept of intelligence validated by consensus, if not a concrete definition. There are at least two problems with Neisser's approach, however. First, there exist multiple prototypes, or ideal cases, not just a single one. Different groups of people have somewhat different prototypes. Which one do we use? If we use all of them, including those of various groups of experts and laymen, we end up with as many ideal concepts of intelligence as there are different prototypes, and we are no better off than we were when appealing to experts' definitions. Secondly, the 'ideal case' approach seems to be an excellent way of discovering what people mean by 'intelligence', but not of discovering what 'intelligence' means. Neisser would argue that the two are indistinguishable, but I suspect they are not. Suppose, for example, that people in some culture view their ideal case as able to harmonize with Kron, the god of nature. This description tells us what these people think intelligence is, but it does not tell us much about the nature of intelligence: we still have to find out what it means to harmonize with Kron. In our culture, an analogous notion might be the ability to adapt to natural events. Again, we still need to find out what kinds of mental events and physical behaviours result in the ability to adapt. What is it that people who are able to adapt well do that people who are not able to adapt well do not do?

Questions such as this have led some theorists of intelligence to seek the nature of intelligence by the analysis of individual differences. The question asked here, as above, is what aspects of mental functioning distinguish more intelligent people from less intelligent ones. The nub of this individual-differences approach is to have people perform a large number of tasks that seem to predict intelligent performance (in school, on the job, or wherever), and to analyse patterns of individual differences in task performance. These patterns of individual differences have usually been analysed through the use of a method of statistical analysis called 'factor analysis'. The idea is to identify the 'factors' of human intellect.

The earliest factorial theory of the nature of intelligence was formulated by the inventor of factor analysis, Charles Spearman. Spearman's (1927) analysis of relations among the kinds of mental tests he and other psychologists had been administering led him to propose a 'two-factor' theory of intelligence. According to this theory, intelligence comprises two kinds of factors — a general factor and specific factors. General ability, or g, as measured by the general factor, is required for performance of mental tests of all kinds. Each specific ability, as measured by each specific factor, is required for performance of just one kind of mental test. Thus, there are as many specific factors as there are tests, but only a single general factor. Spearman suggested that the ability underlying the general factor could best be understood as a kind of 'mental energy'.

Godfrey Thomson's (1939) reassessment of Spearman's individual-differences data led him to accept Spearman's hypothesis of a general factor running through the range of mental ability tests; however, it led him to reject Spearman's interpretation of this factor. Thomson disputed Spearman's claim that the general factor represented a single underlying source of individual differences. Instead, he proposed that the appearance of a general factor was due to the workings of a multitude of mental 'bonds', including reflexes, learned associations between stimuli, and the like. Performance of any particular task activates large numbers of these bonds. Some bonds will be required for the performance of virtually any task requiring mental effort, and these bonds will in combination give rise to the appearance of a general factor.

L. L. Thurstone (1938), like Thomson, accepted Spearman's hypothesis of a general factor. But he disputed the importance of this factor. He argued that it is a 'second-order' factor or phenomenon, one which arises only because the primary or 'first-order' factors are related to each other. What are these primary factors, or, as Thurstone called them, 'primary mental abilities'? Thurstone suggested that they include verbal comprehension (measured by tests such as knowledge of vocabulary), word fluency (measured by tests requiring rapid word production — for example, a listing of as many words as a person can think of that have c as their third letter), number (measured by tests of arithmetical reasoning and computation), spatial visualization (measured by tests requiring mental manipulation of geometric forms), perceptual speed (measured by tests requiring rapid visual scanning, for example, proofreading), memory (measured by tests of recall and recognition of previously presented information), and reasoning (measured by tests such as number series, which require people to say which of several numbers should come next in a given series).

J. P. Guilford (1967) parted company with the majority of factorial theorists by refusing to acknowledge the existence of any general factor at all in human intelligence. Instead, he proposed that intelligence comprises 120 elementary abilities, each of which involves the action of some operation upon some content to produce some product. An example of an ability in Guilford's system is 'cognition of verbal relations'. This ability involves recognition of a conceptual connection between two words: for example, recognition that a caboose is often the last car in a train.

Probably the most widely accepted factorial description of intelligence is a hierarchical one. A good example of this class of descriptions was proposed by P. E. Vernon (1971). He proposed that intelligence can be described as comprising abilities at varying levels of generality: at the highest level of generality (the top of the hierarchy) is general ability as identified by Spearman; at the next level are 'major group' factors, such as verbal–educational ability (the kind of ability needed for successful performance in courses such as English, history, and social studies) and practical–mechanical ability (the kind of ability needed for successful performance in courses such as draughtsmanship and car mechanics); at the next level are 'minor group' factors, which can be obtained by subdividing the major group factors; and at the lowest level (the bottom of the hierarchy) are specific factors, again of the kind identified by Spearman. This description of intelligence may be viewed as filling in the gaps between the two extreme kinds of factors proposed by Spearman: in between the general and specific factors are group factors of intermediate levels of generality.

The factorial views of intelligence are unlike the definitional ones in that they are based on the analysis of intelligent functioning (on ability tests), rather than merely on the speculations of one or more psychologists or laymen. The factorial views are like the definitional ones, however, in their potential number and diversity. Is it the case that one of the factorial descriptions is right and the others wrong, or is it possible that a single entity or complex of entities, intelligence, can conform to all of these different descriptions? In other words, is there some level, or common denominator, at which these various descriptions all reduce to the same thing? It is here suggested that such a level of description exists, and that it can be found by analysing the ways in which people process information when solving problems of the kind found both on intelligence tests and in everyday life.

Information-processing psychologists have sought to understand general intelligence in terms of elementary components (or processes) used in the solution of various kinds of problems (Sternberg, 1979a, 1979b). Let us distinguish five kinds of components that people use in the processing of information. Metacomponents are higher-order control processes that are used for planning how a problem should be solved, for making decisions regarding alternative courses of action during problem solving, and for monitoring one's progress during the course of problem solution. Performance components are processes that are used in the actual execution of a problem-solving strategy. Acquisition components are processes used in learning, that is, in the acquisition of knowledge. Retention components are processes used in remembering — that is, in the retrieval of previously acquired information. Transfer components are used in generalization — that is, in the transfer of knowledge from one task, or task context, to another.

Consider, for example, how each of these five kinds of components might be applied in the solution of an arithmetical problem.

Mrs Smith decided to impress Mrs Jones. She went to a costume jewellery shop and bought three imitation diamonds of equal value. She received £4 in change from the £10 note she gave the assistant. (But as Mrs Smith was receiving her change, Mrs Jones walked into the shop!) How much did each imitation diamond cost?

Metacomponents would be used in setting up the equations for solving the problem, for example, in deciding that the problem can be solved by subtracting £4 from £10 and dividing the difference by three; the metacomponents must also decide what information is relevant to the problem at hand, and what information is irrelevant. Performance components would be used in the actual solution of these equations to obtain, first, £6 as the price of the three imitation diamonds and, then, £2 as the price of each item. Acquisition components were used in the problem solver's past to learn how to set up the equations, how to subtract, how to divide, and so on. Retention components are used to retrieve this information from memory at the time that it is needed. Transfer components are used to draw an analogy between this problem and previous ones: the problem solver has never learned how to solve this particular problem, and must generalize his or her learning from similar problems previously encountered to the problem presently being encountered.

How can this scheme account for the various factorial views of intelligence described earlier? According to this view, the general factor that appears in various theories of intelligence results from the operations of components that are general across the range of tasks represented on intelligence tests. For the most part, these are metacomponents — mental activities such as deciding upon the particular components to be used in the solution of problems, deciding upon a strategy for problem solution, monitoring whether the strategy that has been chosen is leading to a solution, deciding upon how quickly the strategy can be executed and still lead to a satisfactory result, and so on. Major group factors of the kind found in Vernon's theory, and primary factors of the kind found in Thurstone's theory, are obtained in factor analyses primarily as a result of the operations of performance, acquisition, retention, and transfer components. For example, verbal comprehension, as tested by vocabulary, is the product of past executions of acquisition components to learn new words, and of present executions of retention components to retrieve the meanings of these words. If vocabulary is tested by presenting the words in unfamiliar contexts, transfer components may also be involved in applying previously acquired information to the new contexts that are presented. Reasoning, as tested by problems such as numerical series completions (say, 3, 7, 12, 18, 25, ...), requires the execution of various performance components, such as encoding the terms of the problem, inferring the relations between the given pairs of numbers, applying these relations to the last given number to obtain the next number, and the production of a response.

This information-processing view of intelligence seems to unify what were formerly a number of disparate views regarding the nature of intelligence. A number of important questions still need to be answered, however, and it is possible to consider only a small number of them here.

First, is the meaning of intelligence the same across different societal and cultural groups? On the view proposed, the answer is both yes and no. On the one hand, the components that would be applied to the solution of a given problem in one culture or society probably overlap to a large degree, although perhaps not completely, those that would be applied to the solution of the same problem in a different culture or society. On the other hand, the kinds of problems that need to be solved may differ widely from one culture or society to another. The mental (and physical) processes needed to corner game in a hunt are very different from those needed to balance accounts. Hence, the kinds of persons who are considered intelligent may vary widely from one culture to another, as a function of the components that are important for adaptation to the requirements of living in the various cultures.

Secondly, if intelligence tests measure, in greater or lesser degree, the components of information processing, why are they so imperfectly predictive of real-world performance? One reason is that they are fallible as measuring instruments: they measure only imperfectly what they are supposed to measure. Another reason is that they do not necessarily weigh most heavily those aspects of intellectual functioning that are most important for intelligent functioning in a given environment. Metacomponential functioning is probably underemphasized, for example, in the measurements made by most of these tests. Yet another reason, and probably the most important one, is that there is a great deal more to everyday living than what the intelligence tests measure, or even than what can reasonably be called intelligence. The tests fail to take into account such important aspects of functioning as motivation, social skills, persistence in the face of adversity, and ability to set and achieve goals. The tests provide reasonably good measures of limited aspects of functioning for most people. But even here a qualification is necessary, since there are some people whose anxieties, or inability to take tests, render their test scores meaningless or even deceptive.

Finally, is intelligence largely inherited, as has been claimed by some (for example, Jensen 1969), or is it largely or exclusively determined by environment, as has been claimed by others (for example, Kamin 1974)? Few bodies of evidence are more confused and confusing than that dealing with the heritability of intelligence. The probability is that heredity, environment, and the interaction between heredity and environment all play some role in intelligence as it has traditionally been measured, but it is not at all clear what the relative extents of these roles are. Nor is it clear what it means, in practical terms, to assign proportional values to the influence of each. No matter what the proportions are, there is good evidence that at least some aspects of intelligence are trainable, and theoretical interest in the heritability of intelligence should not divert attention from questions about how intelligence can be modified in individuals of all levels of measured intelligence.

(Published 1987)

See also artificial intelligence; guessing and intelligence.

— Robert J. Sternberg

Bibliography
• Boring, E. G. (1923). 'Intelligence as the tests test it'. New Republic, 6 June.
• Gardner, H. (1999). Intelligence Reframed: Multiple Intelligences for the 21st Century.
• Guilford, J. P. (1967). The Nature of Human Intelligence.
• Jensen, A. R. (1969). 'How much can we boost IQ and scholastic achievement?' Harvard Educational Review, 39.
• Kamin, L. J. (1974). The Science and Politics of IQ.
• Neisser, U. (1979). 'The concept of intelligence'. In Sternberg, R. J., and Detterman, D. K. (eds.), Human Intelligence: Perspectives on its Theory and Measurement.
• Spearman, C. (1927). The Abilities of Man.
• Sternberg, R. J. (1979a). 'The nature of mental abilities'. American Psychologist, 34.
• — —  (1979b). 'Stalking the I.Q. quark'. Psychology Today, 13.
• — —  (2000). Handbook of Intelligence.
• — —  and Detterman, D. K. (eds.) (1986). What is Intelligence? Contemporary Viewpoints on its Nature and Definition.
• Thomson, G. H. (1939). The Factorial Analysis of Human Ability.
• Thurstone, L. L. (1938). Primary Mental Abilities.
• Vernon, P. E. (1971). The Structure of Human Abilities.

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IN BRIEF: Capacity to know or understand.

Questions are the creative acts of intelligence. — Dr. Frank Kingdon

LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!

There is no clear, standard definition of intelligence. Psychologists identify intelligence as an individual's adaptation to the environment as fundamental to understanding what intelligence is and what it does. Most researchers agree that intelligence is a person's ability to comprehend their environment, evaluate it rationally, and form appropriate responses.

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1. the ability to comprehend or understand.
2. information gathered about the state of affairs in a farming system, a disease occurrence study, a public health survey or a veterinary service.

n

Mental potential or capacity; an individual’s total repertoire of problem-solving and cognitive discrimination responses that are usual and expected at a given age level and in the large population unit; that which is measured by an intelligence test.

For a list of words related to intelligence, see:

• Types and Techniques of Warfare - intelligence: collection and evaluation of military information regarding enemy
• Espionage and Intelligence - intelligence: political, military, economic, or other information about another state
• Mental States, Processes, and Behavior - intelligence: range of attributes centering around reasoning skills, knowledge of one’s culture, and problem-solving abilities
• Secrecy and Concealment - intelligence: information gathered covertly about enemy activities

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See words rhyming with "intelligence."

  See crossword solutions for the clue Intelligence.

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Common misspelling(s) of intelligence

• inteligence

Dansk (Danish)
n. - intelligens, forstand, begavelse

idioms:

• intelligence agency    efterretningstjeneste, efterretningsvæsen
• intelligence department    efterretningskontor
• intelligence quotient    intelligenskvotient
• intelligence test    intelligenstest

Nederlands (Dutch)
intelligentie, geheime informatie, nieuws, inlichtingendienst, begrip

Français (French)
n. - intelligence, esprit, entendement, (gén, Mil) renseignements, (Mil) service de renseignements

idioms:

• intelligence agency    service de renseignements
• intelligence department    service de renseignements
• intelligence quotient    quotient intellectuel
• intelligence test    test d'intelligence, test d'aptitude intellectuelle

Deutsch (German)
n. - Intelligenz, Nachrichten, Nachrichtendienst

idioms:

• intelligence agency    Nachrichtendienst, Geheimdienst
• intelligence department    Nachrichtendienst
• intelligence quotient    Intelligenzquotient
• intelligence test    Intelligenztest

Ελληνική (Greek)
n. - ευφυϊα, νοημοσύνη, πνεύμα, εμπιστευτικές ή στρατιωτικές πληροφορίες

idioms:

• intelligence agency    υπηρεσία πληροφοριών
• intelligence department    υπηρεσία πληροφοριών
• intelligence quotient    δείκτης ευφυϊας/νοημοσύνης
• intelligence test    δοκιμασία/τεστ νοημοσύνης

Italiano (Italian)
notizia, informazioni, intelligenza, agenzia di informazioni

idioms:

• intelligence agency    agenzia di informazioni, servizio segreto
• intelligence department    Ufficio Informazioni
• intelligence quotient    quoziente di intelligenza
• intelligence test    test di intelligenza

Português (Portuguese)
n. - inteligência (f), informação (f), obtenção e manejo de informações secretas

idioms:

• intelligence agency    agência (f) do serviço secreto
• intelligence department    departamento (m) do serviço secreto
• intelligence quotient    quociente (m) de inteligência (Q.I.)
• intelligence test    prova (f) para determinação de Q.I.

Русский (Russian)
умственные способности, информация, разведка

idioms:

• intelligence agency    разведывательная организация
• intelligence department    разведывательный отдел
• intelligence quotient    коэффициент умственного развития
• intelligence test    проверка умственного развития

Español (Spanish)
n. - información, noticia, inteligencia, servicio de información

idioms:

• intelligence agency    servicio de inteligencia, servicio secreto
• intelligence department    servicio de información o de inteligencia
• intelligence quotient    cociente intelectual o de inteligencia
• intelligence test    test o prueba de inteligencia

Svenska (Swedish)
n. - intelligens, begåvning, underrättelse, ande

中文（简体）(Chinese (Simplified))
智力, 智能, 聪明

idioms:

• intelligence agency    情报机构, 情报局
• intelligence department    情报局, 情报部
• intelligence quotient    智商
• intelligence test    智力测验, 智能测验

中文（繁體）(Chinese (Traditional))
n. - 智力, 智慧, 聰明

idioms:

• intelligence agency    情報機構, 情報局
• intelligence department    情報局, 情報部
• intelligence quotient    智商
• intelligence test    智力測驗, 智慧測驗

한국어 (Korean)
n. - 지능, 지성적 존재, 정보

日本語 (Japanese)
n. - 理解力, 知能, 聡明, 知性, 報道, 情報, 諜報機関

idioms:

• intelligence agency    喋報員
• intelligence department    情報部
• intelligence quotient    知能指数
• intelligence test    知能検査

العربيه (Arabic)
‏(الاسم) ذكاء, عقل, تفكير‏

עברית (Hebrew)
n. - ‮משכל, שכל, אינטליגנציה, תבונה, ביון, מודיעין‬

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