As I explained here, the scientific consensus is that intelligence is general. That is, if you are good at verbal comprehension, you’ll also tend to be good perceptual organisation, and if you’re good at maths, you’re also likely to be good at English. This is counter-intuitive. Most people believe that mental abilities trade off against each other and the doing well in one area means doing poorly in another. Of course, this might be true for some people, but just because your mate John can barely count his own fingers but happens to be a literary genius, doesn’t disprove the fact that this is a statistical likelihood. The tendency for mental abilities to correlate with each other leads to what’s called the general factor of intelligence.

But just because this is the consensus view on intelligence research doesn’t mean there aren’t those who disagree. One such dissenter is Howard Gardner. In 1983, Gardner came up with his Theory of Multiple Intelligences. In essence, what he said was that instead of there being one general intelligence there were lots of different types of intelligence: logical-mathematical, linguistic, musical, intra and extra personal and so on. Contrary to the mainstream position, he claimed that while someone might have a low linguistic intelligence they might do very well in, say, naturalistic intelligence. This is a seductive idea, but one for which there is little support. Gardener never tested his theory or conducted any studies. It was just a hunch. A popular and enduring hunch to be such, but one of which even Gardener himself said in 2016, “I readily admit that the theory is no longer current.”

Of course, he’s not quite ready to entirely abandon his theory. While he admits that he never carried out any experiments designed to test his theory, he’s not willing to accept that it lacks empirical support. He says, “The theory is not experimental in the traditional sense … but it is strictly empirical, drawing on hundreds of findings from half-a-dozen fields of science.” I’m not at all sure this is good enough.For his theory to stand up against the weight of evidence stacked against it, it would need something pretty special to support it. Just because you’ve got a lot of data, it doesn’t mean that you understand what it’s telling you. One of the central pillars of science is that because it’s all too easy to prove yourself right, to really test your claims you have to try to disprove, or falsify them. Gardner’s argument is a classic closed circle: I’m right because I have a lot of data which says I’m right. How does he know the data’s correct? Because he’s got a lot of it. A closed circle argument is one where there is no possibility of convincing an opponent that they might be wrong. They are right because they’re right.

But, maybe there’s a ray of hope for Gardner’s theory? This recent paper claims to provide empirical support for Multiple Intelligences. After “reviewing 318 neuroscience reports it concludes “there is robust evidence that each intelligence possesses neural coherence.” That sounds pretty convincing, but what does it actually mean? Basically this: researchers trawled though neuroscience studies to find indications in cortical areas for each of Gardner’s eight intelligences. And guess what? Brain imaging reveals that people really do have brain regions dedicated to each area. So does this provide much needed empirical support for Multiple Intelligences? No. All it tells is that what we already knew: there are various brain regions associated with musical ability, physical movement, communication, handling figures etc.

It really doesn’t come as much of surprise to find out that mental abilities are located in the brain. This has never been in doubt. And this is the whole problem with Gardner’s theory. He admits that if he’d steered clear of the word ‘intelligence’ no one would have given his idea a second glance. It’s completely uncontroversial to say different people have different talents, but by calling these talents intelligences he poisoned the well of intelligence research and strayed into pseudoscience.

But let’s be charitable for a moment and assume that this new paper did provide empirical support for Multiple Intelligences. The question we have to ask ourselves is, so what if Gardner is right? What difference could it possibly it make to teachers to discover that some children are musical and others like nature? How would this change what teachers do in classrooms? Just because someone has ‘naturalistic intelligence’ does this mean they need to be taught maths in a garden? Would possessing high ‘linguistic intelligence’ mean you wouldn’t appreciate art? As we know from research into learning styles, matching instruction to children’s perceived preferences only serves to narrow their experiences.

The bottom line is this: The Theory of Multiple Intelligences is conceptual confused, lacks experimental support, flies in the face of more generally accepted, mainstream scientific research on intelligence, and, most importantly, provides absolutely nothing of any practical value to teachers. You might as well rely on something as obviously risible as thinking hats