You might have heard of the theory of Multiple Intelligences, but what is the evidence behind it? If there aren't multiple intelligences, are there multiple abilities? In what ways can intelligence and cognitive abilities be reasonably measured? How can intelligence and cognitive abilities be useful in education? These are some questions I posed to Russell T. Warne, author of the new book In the Know: Debunking 35 Myths About Human Intelligence. Following are Warne's responses to a small sample of the numerous questions about human intelligence that he answers in his full book.

What is the difference between the theory of Multiple Intelligences and multiple cognitive abilities?

"Howard Gardner's theory of multiple intelligences is that there are at least 7 and up to 9 intelligences, depending on which version of the theory that you prefer. These intelligences are—in Gardner's words—"relatively independent" and function in specific domains in people's lives, such as the social domain (interpersonal intelligence), physical domain (bodily-kinesthetic intelligence), or musical domain (musical intelligence). In contrast, the mainstream theory among psychologists is that there is a general intelligence that helps people function in all contexts of life that require cognitive functioning. This general intelligence is related to broad abilities, such as verbal ability, processing speed, and abstract reasoning. The disagreement is over two questions: (1) whether there is a general ability, and (2) whether other cognitive abilities are correlated. Gardner says no to both questions. Most other experts say yes. The empirical evidence is strong that Gardner is wrong on both counts."

In what ways can intelligence or cognitive abilities be reasonably measured?

"One myth I address is that it is difficult to measure intelligence. The reality is that it is one of the easiest psychological traits to measure. Because intelligence is general, any task that requires some sort of cognitive effort will measure intelligence. Academic tests, short-term memory tasks, logic problems, pattern completion, and many, many other tasks can all measure intelligence. In fact, I discuss in the book examples of people who have accidentally created tests of general intelligence when they were trying to measure something else! However, that does not mean that all tasks are equally good at measuring intelligence. When psychologists devise intelligence tests, they prefer tasks that are better measures of intelligence. That means that abstract reasoning tasks, which require a lot of cognitive work, appear often on these tests, but reaction time tasks, which require very little cognitive effort, rarely do."

In what ways can intelligence or cognitive abilities be useful in education?

"I admire K-12 educators who are in the trenches every day teaching kids and building the academic skills and knowledge that people need to succeed in society. However, teachers are often misinformed about some of the basic facts about intelligence. This is disappointing because intelligence is one of the best predictors of academic performance. As an example, I would like to see intelligence or aptitude test scores being used to identify children who could skip a grade. About one-quarter of high school juniors in my state are college-ready in math, science, language arts, and social studies. These students don't need a senior year and could skip ahead to college now. But nationwide, only about 2-3% of students skip a grade during the course of their K-12 career. Identifying these students and advancing them could provide long-term benefits. Other educational decisions would be better made by considering students' intelligence levels, such as grouping students together by ability so that students move through the year's curriculum at more-or-less the same speed as their classmates. However, I do not think that long-term placement in remedial courses or vocational tracks should be decided solely on the basis of intelligence test scores. Moreover, students in these programs should be re-evaluated regularly to see if they are making enough progress to be placed in a more rigorous academic environment."

References

Warne, R. T. (2020). In the know: Debunking 35 myths about human intelligence. Cambridge, MA: Cambridge University Press.

This article originally appeared at Psychology Today.