IQ Tests: Perfect Measures for Different Types of Intelligence?


By Catherine A. SandersonAmherst College

Our society sees admission to top schools as a key pathway to success. Standardized test scores offer colleges a way to distinguish between thousands of applicants, with the hope that such scores reveal something important about students’ intelligence and potential for college success. So, do these scores really measure intelligence? And what, in fact, is intelligence?

IQ and fractions test based on logical tasks
Colleges use standardized tests to measure applicants’ intelligence. (Image: cmldncr35/Shutterstock)

General Intelligence

Early in the 20th century, British psychologist Charles Spearman was the first to observe that high scores on different types of tests of mental abilities—reasoning, problem-solving, memory, and so on—all correlated with one another. This led him to propose that a single factor, which he called general intelligence, underlies performance on all types of cognitive abilities. 

Spearman described general intelligence as a single dimension that helps us acquire, remember, and use knowledge to solve problems, learn from experience, and adapt to new situations.

He referred to general intelligence with the letter g and began the practice of generating scores for people ranging considerably, from “very smart” to versions of “not so smart”. However, a number of other researchers, later on, suggested that intelligence has more than one factor.

Fluid Intelligence Versus Crystallized Intelligence 

One distinction we’ve already encountered when considering cognitive development is that intelligence consists of two distinct types of skills and abilities. Teenagers and young adults are especially strong in fluid intelligence, meaning the ability to basically use our minds to think and reason on an abstract level, and to do so pretty rapidly. 

Indeed, one of the hallmarks of this kind of intelligence is thought to be the degree to which it is not based on what you’ve learned. Fluid intelligence is considered independent of learning, experience, and education. Conversely, older adults tend to be stronger in crystallized intelligence, meaning the wealth of knowledge and skills you acquire because you have more life experiences, have read more books, have more education, and so on.

This article comes directly from content in the video series Introduction to PsychologyWatch it now, on Wondrium.

The Theory of Multiple Intelligences

Robert Sternberg, a long-time professor of psychology at Yale University, created a broader model that he described as “successful intelligence”. First, there’s analytical intelligence, meaning how you evaluate information and solve well-defined problems. This is what is often assessed in standardized tests. 

But there’s also creative intelligence, meaning how well can you react to novel situations and come up with new ideas. And there’s practical intelligence, meaning how well can you solve everyday tasks and adapt to changing environments.

Similar to Sternberg, Harvard psychologist Howard Gardner, thought that intelligence is more than a single dimension. His theory of multiple intelligences says that each of us have different profiles of intelligence and are stronger in some areas than in others. In short, intelligence is multifaceted. 

Concept of Multiple Intelligence Theory
Howard Gardner and Robert Sternberg suggested that intelligence is not a single dimension, so they introduced many distinct types. (Image: Sajaganesandip/Public domain)

According to Gardner’s original version of this theory, there are seven distinct types of intelligences:

Musical—recognizing and remembering sounds and rhythms.

Bodily/kinesthetic—having good physical coordination and motor control.

Visual-spatial—visualizing information and reading charts and graphs.

Linguistic/verbal—writing stories, reading, and memorizing.

Logical/mathematical—reasoning and analyzing problems.

Intrapersonal—understanding their own feelings and motivations.

Interpersonal—understanding and relating to people.

He later added two additional types of intelligence: Naturalistic—being in tune with nature and the environment; and existential—the ability to ask fundamental questions about human existence.

The Stanford-Binet Intelligence Scale

What Gardner and Sternberg were reacting against was the tradition of measuring general intelligence first pioneered by Alfred Binet early in the 20th century. Binet had been asked to determine a way to assess children’s varied cognitive abilities in order to figure out which children in France would be placed in a special school for mentally challenged kids. 

He created a measure of “mental age”, meaning the age at which a child was able to perform various tasks. So, a gifted five-year-old might have a mental age of seven; a mentally challenged seven-year-old might have a mental age of five.

In the United States, Lewis Terman, a professor at Stanford University in the early to mid-1900s, developed his own test to measure children’s intelligence. His test, which was loosely modeled on the test developed by Binet, is known as the Stanford-Binet Intelligence Scale. This test examines different types of cognitive ability, including general knowledge, visual-spatial processing, quantitative reasoning, and memory. 

A child’s overall mental capacity is determined by dividing their score on this test—which assesses their mental age—by their chronological age, and then multiplied this number by 100. Thus, someone whose mental age is the same as their chronological age would have a score of 100.

Are IQ Tests Good Measures to Predict One’s Smartness?

IQ tests are still widely administered and remain heavily focused on cognitive skills, and not on others’ social skills. Overall, such tests are useful ways of classifying people from a given culture and background in terms of some particular abilities. Many of the skills assessed by these tests are those valued in society, such as the ability to remember information, solve problems, and work quickly. 

And research does show that scores on general measures of intelligence do predict success in school and work environments pretty well; not perfectly, but pretty well. However, IQ tests are not perfect measures or predictors of anything, which is why these tests should never be used in isolation, but rather in combination with other information (grades, teacher letters, achievement tests, and so on).

Common Questions about IQ Tests and Different Types of Intelligence

Q: What is general intelligence?

According to Charles Spearman, general intelligence is a single dimension that helps people use their acquired knowledge to adapt to new situations, learn new things, and solve problems. General intelligence is referred to as the letter g, and, according to it, people are classified from “very smart” to “not so smart”.

Q: What are fluid intelligence and crystallized intelligence?

Fluid intelligence is the ability to rapidly use the mind to think and reason, and it is independent of education and learning. On the other hand, crystallized intelligence means the ability to use the knowledge and experience that are acquired through life. Older people are stronger in this type of intelligence, whereas younger people tend to be stronger in fluid intelligence.

Q: What are the different types of intelligence according to Gardner’s theory?

Howard Gardner suggested that intelligence is multifaceted as there are different types of intelligence, including musical, bodily/kinesthetic, interpersonal, intrapersonal, linguistic/verbal, logical/mathematical, visual-spatial, naturalistic, and existential.

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