THEORIES OF INTELLIGENCE

Intelligence theorists fall into two categories. In one group are those who argue for a "general intelligence" that characterizes a person’s actions and thinking in all areas. Their critics believe that intelligence is composed of many separate types of aptitudes and abilities, and that a person who excels in one area will not necessarily excel in all areas.

Spearman believed that intelligence is general: People who are bright in one area are bright in other areas as well. Thurstone disagreed: He believed that intelligence encompasses seven mental abilities that are relatively independent of one another.

In contrast, Cattell divided mental abilities into two clusters. The first is crystallized intelligence, or abilities such as reasoning and the verbal and numerical skills that are stressed in school. The second is fluid intelligence, or skills such as spatial and visual imagery, the ability to notice visual details, and rote memory.

In the mid-1980s, Yale psychologist Robert Sternberg proposed a triarchic theory of intelligence that includes a much broader range of skills and abilities. According to this theory, intelligence consists of three overarching aspects: componential intelligence, the traditional mental processes or skills emphasized by earlier theories of intelligence, such as the ability to acquire new knowledge and perform tasks efficiently; experiential intelligence, characterized by insight and creative adaptability as well as efficient and quick processing of information without conscious thought; and contextual intelligence, marked by responsiveness to the environment. Intelligent people, according to Sternberg, are adept at making the most of their strengths and compensating for their weaknesses.

Howard Gardner has proposed his theory of multiple intelligences, which asserts that what we refer to as intelligence actually consists of many separate abilities, each of which is relatively independent of the others.

Formal theories of intelligence serve as the foundation for the design and administration of intelligence tests. And because experts do not view intelligence in exactly the same way that nonexperts do, it is understandable that most tests of intelligence do not include items that many nonexperts think of as part of intelligence.