Theories of intelligence: a multifaceted concept

Charles Spearman's General Intelligence (the "g" factor)

Psychologist Charles Spearman believed that we all possess a single general intelligence that lies at the heart of all our intelligent behavior.

This general factor, known as the "g" factor, is what explains why people who score high in one area, such as verbal intelligence, also often score above average in others.

Although Spearman conceded that people can have special, outstanding abilities, his theory suggests that all of our intellectual abilities are connected by this underlying factor.

This view proposes that intelligence can be represented by a single number or score, a concept that has been instrumental in the development of many IQ tests.

Howard Gardner's Multiple Intelligences

In direct contrast to the idea of a general factor, Howard Gardner developed an influential theory proposing the existence of at least eight intelligences.

According to this view, these different forms of intelligence are relatively independent of one another, which explains why a person may excel in one area.

Gardner identified intelligences such as linguistic, logical-mathematical, musical, spatial, interpersonal, intrapersonal, and naturalistic, among others.

For him, a programmer, a poet, and a point guard on a basketball team demonstrate different types of intelligence, which cannot be measured by a single scale.

Each of these multiple intelligences, in his view, is linked to a system that is independent within our own brains.

Robert Sternberg's Triarchic Theory

Robert Sternberg agrees with Gardner that there is more than one type of intelligence, but his triarchic theory proposes three different types, not eight.

The first is analytical intelligence, which is used in academic problems and measured by traditional intelligence tests.

The second is creative intelligence, which is demonstrated by reacting adaptively to new situations and generating ideas that are completely novel.

The third is practical intelligence, which is required for everyday tasks and is often described as "common sense" or "street smarts."

Fluid and Crystallized Intelligence

Finally, some psychologists have suggested the existence of two different types of intelligence, which are fluid intelligence and crystallized intelligence.

Fluid intelligence reflects our abilities to process information, as well as our reasoning skills and the functioning of our own memory.

In contrast, crystallized intelligence is the accumulation of information, skills, and strategies that people have learned through experience.

Crystallized intelligence, which is based on accumulated knowledge, is the intelligence we generally apply in our lives to solve different problems.