Is IQ a load of BS?

Long ago, when the rocks were young and the winds were new, the Nightingale, Peacock, and Falcon gathered together to decide which one was best.

“Let us sing a beautiful song,” the Nightingale said, and surprise, surprise, the Nightingale won.

“Let us flaunt our beautiful feathers,” the Peacock said, and surprise, surprise, the Peacock won.

“Let us fly, as fast as we can,” the Falcon said, and surprise, surprise, the Falcon won.

“So, which of you is best?” the weary Owl sighed, and no one could tell him who.

Intelligence tests

At the turn of the 20th century, people were falling over themselves trying to make the test to objectively measure intelligence. It was based on the common assumption that all kinds of intelligence — verbal reasoning, spatial awareness, memory, and so on — were simply manifestations of some central, basic general intelligence. The first test to measure this general intelligence was well intentioned. It originated in France and was designed to identify which children would need extra help at school. This test, known as the Binet-Simon test, eventually became the model on which all IQ tests today are based.

The test presents a series of questions, each scripted to test an aspect of this general intelligence. The final score is then divided by age and multiplied by 100 to give a “percentile.”

It wasn’t long, however, before the tests were turned to ill. Children as young as three are told they are of below-average intelligence based on a series of questions inspired by a century’s old psychology. Racists have long used IQ as an “objective” measure of racial superiority. The Nazis used versions of these tests to “prove” that certain ethnicities were subhuman. They used it to justify forcible sterilizations or the murder of children considered of an insufferably low IQ.

In 1927, the U.S. Supreme Court voted 8-1 in Buck v. Bell to allow states the right to forcibly sterilize those they deemed “mentally deficient” by these tests. Justice Oliver Wendell Holmes infamously wrote: “Three generations of imbeciles are enough.” It’s thought that roughly 70,000 people were victims of this ruling.

Schools, employers, and entire industries have been known to disqualify a candidate based on their IQ. Today, IQ tests are imprinted into our lexicon. Idiots were those whose intelligence never went above that of a two-year-old’s. Imbeciles were those who didn’t reach the IQ of a seven-year-old. Morons were those no higher than twelve.

What’s IQ good for?

Just because something has, historically, been used for immense evil doesn’t necessarily mean it is, in itself, unfit for purpose. So, with what we know today, how far should IQ be trusted?

To answer that question, we have to first ask what IQ is. These days, most reputable IQ tests or psychologists will openly admit that IQ is not a complete measure of how smart you are. These tests do not tell you, nor are they intended to tell you, your overall cognitive prowess. What IQ does measure is something called “general mental ability” (for example, pattern recognition), also called g. The Raven Matrices, one of the most popular tests, is pretty reliable at telling you what a person’s g might be. There are many other more specific tests that can investigate particular cognitive aspects — like memory, verbal reasoning, mathematical ability, and so on. If you want to know someone’s g, then an IQ test is the best tool for the job.

Additionally, there does seem to be at least some evidence pointing toward a correlation between someone’s g and their overall academic and professional success. Personality traits such as agreeableness, conscientiousness, trust, and generosity also feature highly in indicating future success, but, as one study puts it, “Higher intelligence results in significantly higher… earnings.” Personality matters, but IQ matters a bit more.

There’s also a practical aspect to IQ. In a world where large organizations, from the military to multinational corporations, insist on some kind of psychometric testing, IQ tests might be the best we have available.

Not fit for purpose

But, there are two major problems with IQ.

The first problem with IQ stems from those who misunderstand what it’s trying to measure. IQ measures your score on a test against the averages of everyone else taking that test. It tells you how good someone is at answering certain types of questions, as compared with others. Thus, it’s not about an absolute intelligence, but relative intelligence. The trouble occurs when people misunderstand this point. They assume IQ represents raw “brain power.” Worse, some people equate IQ with worth. Employers, especially, might write off a person based on a low IQ. Doing so fails to appreciate that many employees can offer skills and abilities that lie beyond the scope of IQ tests (such as personality factors like conscientiousness).

Furthermore, the correlations mentioned above — that is, those between IQ and success — are still, statistically, considered small ones. Additionally, we cannot rule out many other factors clouding the issue. As one meta-analysis concludes, “A closer look at the data and results… suggests a rather murkier picture.” In short, the data we have — the data some people use to pigeon-hole a person for life — is desperately weak and inconclusive.

The second problem is that IQ is far too narrow a metric to dominate so much of the psychometric landscape. IQ represents only one, or a few, kinds of intelligence. Even the ancient Greeks knew there were different types of intelligence. For example, there was techne (vocational skills), episteme (general knowledge), phronesis (practical wisdom), or nous (a kind of rational intuition). In an interview for Big Think, the psychologist Howard Gardener identifies eight different kinds of intelligence, and “IQ tests and other kinds of standardized tests valorize” only two of them.

Best bird competition

So, is IQ BS? Well, it’s complicated. IQ is a test, designed to gauge a certain type of intelligence, which some argue (on weak data) is a good indicator of lifetime success. It ranks people against each other, when no other information (such as examinations or qualifications) can meaningfully help in that ranking.

Headlines like “Ways to improve your IQ!” seem to reveal what IQ is — an examination. And, like any exam, you can game and train for it. The fact that you can improve (and, presumably, degrade) your IQ reveals a still more fundamental point: IQ is not a measure of who you are. It isn’t something structural to your being, unchangeable and predetermined (such as your genetics).

Human society is diverse. No one is identical, and no two people will approach a problem in quite the same way. Each of us is better and worse at different aspects of life. When employers seek to hire only one type of person, they risk missing the benefits of what others — those beyond the remit of IQ tests — can provide.

So, yes, if you want a beautiful bird, hire a Peacock. If you want a fast one, get a Falcon. But as the weary old Owl knows, there is no such thing as a Best Bird Competition.

Jonny Thomson teaches philosophy in Oxford. He runs a popular account called Mini Philosophy and his first book is Mini Philosophy: A Small Book of Big Ideas.