The following are some of the major theories of intelligence that have emerged during the last 100 years.
Charles Spearman - General Intelligence:
British psychologist Charles Spearman (1863-1945) described a concept he referred to as general intelligence, or the g factor. After using a technique known as factor analysis to to examine a number of mental aptitude tests, Spearman concluded that scores on these tests were remarkably similar. People who performed well on one cognitive test tended to perform well on other tests, while those who scored badly on one test tended to score badly on others. He concluded that intelligence is general cognitive ability that could be measured and numerically expressed.
Louis L. Thurstone - Primary Mental Abilities:
Psychologist Louis L. Thurstone (1887-1955) offered a differing theory of intelligence. Instead of viewing intelligence as a single, general ability, Thurstone's theory focused on seven different "primary mental abilities." The abilities that he described were:
- Verbal comprehension
- Perceptual speed
- Numerical ability
- Word fluency
- Associative memory
- Spatial visualization
Howard Gardner - Multiple Intelligences:
One of the more recent ideas to emerge is Howard Gardner's theory of multiple intelligences. Instead of focusing on the analysis of test scores, Gardner proposed that numerical expressions of human intelligence are not a full and accurate depiction of people's abilities. His theory describes eight distinct intelligences that are based on skills and abilities that are valued within different cultures.
The eight intelligences Gardner described are:
- Visual-spatial Intelligence
- Verbal-linguistic Intelligence
- Bodily-kinesthetic Intelligence
- Logical-mathematical Intelligence
- Interpersonal Intelligence
- Musical Intelligence
- Intra personal Intelligence
- Naturalistic Intelligence
Robert Sternberg - Triarchic Theory of Intelligence:
Psychologist Robert Sternberg defined intelligence as "mental activity directed toward purposive adaptation to, selection and shaping of, real-world environments relevant to one’s life." While he agreed with Gardner that intelligence is much broader than a single, general ability, he instead suggested some of Gardner's intelligences are better viewed as individual talents.
Sternberg proposed what he refers to as 'successful intelligence,' which is comprised of three different factors:
- Analytical intelligence: This component refers to problem-solving abilities.
- Creative intelligence: This aspect of intelligence involves the ability to deal with new situations using past experiences and current skills.
- Practical intelligence: This element refers to the ability to adapt to a changing environment.
Gardner, H. (1983). Frames of mind: The theory of multiple intelligences. New York: Basic Books.
Spearman, C. (1904). "General intelligence," objectively determined and measured. American Journal of Psychology 15, 201-293.
Sternberg, R. J. (1985). Beyond IQ: A Triarchic Theory of Intelligence. Cambridge: Cambridge University Press.
Thurstone, L.L. (1938). Primary mental abilities. Chicago: University of Chicago Press.