Why do clever people do stupid things? Psychologists split on 'link' between IQ and lack of common sense

The "nutty professor" stereotype has done a lot to cement the idea that highly intelligent types are not very good at the practicalities of day-to-day life.

And while changing a plug or reading a map are not considered "rocket science" by most of the population, it might be rocket scientists who struggle most with them.

Yet the claim that a high IQ is conclusively linked to a lack of common sense is disputed, with some psychologists saying the trope is a convenient way for men - so often assumed to be the "geniuses" - to shirk many of the all-round duties which women are simply expected to handle.

As International Women's Day highlighted, women spend two hours more a day than men in unpaid work - and only when she earns more than her male partner does he do the same amount of housework that she does.

Anita Abrams, a clinical psychologist and an associate fellow at the British Psychological Society, said this kind of dynamic meant highly intelligent men were often able to appear "incapable" in the rest of their personal lives without social criticism.

"Men are allowed to be introverted and have their curious interests and be allowed off interaction at a basic polite level," she said.

"They usually confined all other practicalities, such as having a clean shirt for tomorrow, to a secretary or wife."

And being male or female could determine how much an intelligent person is allowed to focus on their particular interest, she said.

"Women are expected to have a bigger range of skills," said Dr Abrams.

Common sense is variously described by psychologists as a form of practical "decision-making" as well as the "ability to imagine the consequences of an action".

This makes some intelligent people on the Autism Disorder Spectrum appear to lack common sense to other people, said another expert.

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"Common sense is often the ability to imagine the consequences of something you do," said Dr Jane McCartney, a chartered psychologist working in south east London.

"Autism has a lack of imagination as one of the diagnostic criteria, so they often seem to lack common sense."

At the same time, the two qualities were not mutually exclusive, since someone with a lot of common sense could also be very intelligent, she added.

But one major study has claimed to prove a link between a high IQ and a lack of common sense.

Bruce Charlton, an evolutionary psychiatrist at Newcastle University, published a study which claimed very intelligent people were lacking in certain other brain functions that could make them appear "silly" in social situations.

"An increasing relative level of IQ brings with it a tendency differentially to over-use general intelligence in problem-solving, and to override those instinctive and spontaneous forms of evolved behaviour which could be termed common sense," he said in his study.

"When it comes to solving social problems, the most intelligent people are more likely than those of average intelligence to have novel but silly ideas, and therefore to believe and behave maladaptively."

But Dr McCartney said: "There's an element of people playing up to this stereotype.

"There are a few people who genuinely can't help themselves, but generally people can."