So it turns out that after all the rows about the washing up, the shopping and the school run, men are not from Mars nor women from Venus. Both sexes are, rather prosaically, from Earth. And, despite anecdotal evidence to the contrary, men and women do speak the same language.

At least we do according to Deborah Cameron, Britain’s pre-eminent feminist philologist (not often that you meet one of them) and the current Rupert Murdoch professor of language and communication at Oxford University.

Cameron, 48, is a firebrand with an impressive list of pet peeves, including Tories, Darwinists, GNER’s passenger service announcements, Big Brother’s language “so-called” experts, man-hating “pseudo-feminists” and societies for the protection of the semicolon. Don’t get her started on Lynne Truss.

But the subject that has irked her most recently – enough for Cameron to dedicate an entire book to bludgeoning its brains out – is what she calls The Myth of Mars and Venus, published last week by Oxford University Press. In it Cameron tears into such seminal works as John Gray’s Men are From Mars, Women are From Venus and Deborah Tan-nen’s You Just Don’t Understand: Women and Men in Conversation.

These texts, and their bandwagon-hopping cousins, have shipped hundreds of thousands of copies in the past 15 years by espousing the theory that men and women are genetically unsuited to communicating successfully with each other. It’s time, says Cameron, for the nonsense to stop.

“I’m afraid I think John Gray comes from Uranus,” says Cameron, in a joke she may have rehearsed. “It’s pretty annoying that people like him have made millions peddling this nonsense.”

The bones of Cameron’s argument, set out in The Myth of Mars and Venus, are that Gray et al have no scientific basis for their claims. Great sheaves of academic papers, says Cameron, show that the language skills of men and women are almost identical. Indeed, the central tenets of the Mars and Venus culture – that women talk more than men, that men are more direct, that women are more verbally skilled – can all be debunked by scientific research. A recent study in the American journal Science, for instance, found men and women speak almost exactly the same number of words a day: 16,000.

“The main thing about the book is that I wanted to offer people more than the evidence-free rubbish they get every day,” says Cameron. “My pitch was basically the CSI pitch: let the evidence tell the story.”

Where the book becomes interesting is when she asks why we have become interested in these myths. “The first point to make is that in the past 20 years we have become obsessed by communication,” she says. “And that’s not just in relationships; it’s in customer care, it’s in politics. All problems are seen to be communication problems.

“If, for instance, anyone disagrees with someone else, it’s seen to be because they don’t understand each other. Well, actually you could understand me and still disagree with me. Likewise, if a train is delayed or cancelled, all anyone’s interested in is whether there is an appropriate announcement. Communication has become a substitute for actual problem solving.

“Where this relates to the Mars and Venus books is that they say problems in relationships between men and women are all down to communication. The misunderstandings are not, for instance, about the fact that men and women are both vying for jobs, or power, or status, or time. That’s quite comforting to a lot of people.

“There has been a revolution in gender politics – there is much more blurring between the roles of men and women – and I think a lot of men and women are uneasy about that. Books like Mars and Venus tell us that although men and women may be very similar on the outside, we are profoundly different on a deeper level – that we’re ‘hard-wired’ differently.”

Where Cameron is most convincing is in her portrayal of modern relationships where, unlike our grand-parents’ generation, we now put a huge amount of weight on a few relationships, particularly those with our companions. “My grandmother never expected to have long, intimate discussions with my grandfather,” says Cameron. “In the northern working-class community where they lived, women talked to women and men to men.

“Now we all expect not just to have a partner for life but a companion for life. In general, too, we have fewer people to whom we talk regularly; so a few people have to bear the responsibility to support us emotionally. We can be very disappointed when the person we’re in a relationship with doesn’t turn out to be telepathic.”

Cameron is not simply irritated that the Mars and Venus books have filled too many Christmas stockings. Her fervour on this issue runs deeper. There is, she thinks, something regressive, deeply conservative, in this outlook because what it seems to be saying is that we can’t change.

In the Mars and Venus world view, women stay women, chatting (probably too much) and being unable to say exactly what they mean, while men get on with their straightforward competitive existences. It’s a view, she feels, that does neither men nor women any favours.

“I realise that women are peddling this stuff as much as men,” says Cameron. “There is a cheap way for women to feel good in this myth. They are portrayed as sympathetic, good at communicating, whatever. Men, on the other hand, are autistic, inarticulate Neanderthals. If you’re a woman, that’s a way of feeling good about yourself when it’s still quite likely that the man you’re with earns more money than you. It’s a big trap for women.”

What does the collusion of millions of women in this “big trap” say about the state of Noughties gender politics? “It’s possible that we’re in a postfeminist moment,” she says. “There is a strain of conservatism running through these books that says, ‘Wouldn’t we all be better if we returned to our old gender roles’.”

The rate of change in social and sexual relations has been so quick, Cameron says, that it has startled us. Aspirant and affluent men and women now look the same – women wear jeans and work out; men groom – and, more importantly, they want the same things.

“Again I go back to my grand-parents’ generation. It was very clear then who was who and who did what,” she says. “But now, in our aspirations and outlook on lives, educated men and women are very similar.”

This, argues Cameron, is a difficult change, one that has caused resistance. Hence the success of the Mars and Venus myth, because what could be more comforting to men and women in a world in flux than a reaffirmation of traditional roles?

Cameron has been here before. Indeed, swap the central characters around and one could almost be talking about her 1995 book, Verbal Hygiene. With debates about the English schools curriculum raging in the background, Verbal Hygiene not only skewered grammar fundamental-ists but also wondered why the campaign for proper syntax had become such an emotional issue.

“You had people like Prince Charles and Norman Tebbit inferring that if people were making spelling mistakes it was only a short step to them coming in dirty to school and then there’d be no motivation for them to stay out of crime,” says Cameron. “There were these illogical slippery slope arguments: how, if children didn’t know how to use the colon properly, it was only a few steps from drug-taking and criminality. There was a deep moral and social dimension to it all.

“It’s the same with modern pop linguists like Lynne Truss. Linguistic standards very quickly become substitutes for moral ones. For a lot of pop linguists, punctuation is a mark of rectitude, about respect for your reader. Actually, what’s happening is just what happens to language: it changes.”

The relationships between men and women change, too, she says, but try telling the Mars and Venus crew. An argument about whether “I don’t suppose there’s any tomato ketchup” is a veiled instruction or a genuine question might seem trifling, but for Cameron at least the argument is political – because, outside the domestic sphere, the Mars and Venus myth is informing arguments whose stakes are much higher.

One acute observation in The Myth of Mars and Venus revolves around rape trials where, Cameron believes, Mars and Venus logic has become the ultimate get-out clause for defendants. Cameron cites one rape trial in Canada in the 1990s where the female complainant is asked: “Did it occur to you through the persistent behaviour that maybe your signals were not coming across loud and clear”, while the male complainant states simply: “She said that she was tired but she never said like ‘no’, ‘stop’, ‘don’t’.”

Cameron argues that both men and women are perfectly capable of understanding what a woman saying ‘I’m tired’ and feigning unconsciousness means, but no one thinks to ask why the defendant is being so obtuse. The complainant, on the other hand, is roasted for not being direct enough. The myth of Mars and Venus bolsters a great escape route for the defendant: miscommunication.

Even when there is less on the line, men can use the miscommunication ticket to their advantage. Ask any man who has failed to do the washing up after being asked, “Do you think you might have time to do the dishes?”

“Of course everyone knows what is being talked about,” says Cameron, “because in other situations men can understand and make indirect requests. But it’s sometimes convenient for one party to misunderstand. The Mars and Venus myth says this misunderstanding is an inalienable fact of male and female relationships, but it’s not. The only thing you’ve proved is that the man is a lazy arse.”

Cameron has work to do to if she wishes to debunk the entire Mars and Venus cottage industry. Hardly a day goes by without some new piece of research telling us why women can’t issue instructions or men have difficulty communicating in groups.

The truth is that the truth is boring. When it comes to the sexes, differences are much more interesting than similarities. “There’s a postcard that a few friends of mine have sent me,” says Cameron. “It reads, ‘Men are from Earth. Women are from Earth. Deal with it’. That pretty much sums it up. The trouble is, that’s not very exciting. A book called Men and Women Understand Each Other Pretty Well Most of the Time isn’t going to sell too many copies, is it?”

Don’t be ridiculous – of course you understand me, darling

Myth 1: women talk more than men Nonsense, says Cameron. In a popular self-help book, The Female Brain, the claim is made that women say 20,000 words a day and men only 7,000. This statistic has been widely reported in newspapers and journals but has since turned out to be erroneous and based on no real research. It has since been removed from the book.

In fact a number of studies have found that men speak more than women, although others found that women speak more than men. A recent study by the University of Arizona, on a group of undergraduates, found that both sexes spoke an equal number of words a day – 16,000.

Myth 2: men and women communicate differently More hogwash, says Cameron. Linguistic studies have shown that men and women share a 99.75% overlap in the way they communicate. If there are differences in the way the sexes communicate, they are infinitesimal.

The only real markers of difference between men and women are that women smile more and spell better, and it is, says Cameron, only a “moderate difference”.

Myth 3: men’s and women’s brains are hardwired differently when it comes to language This area, says Cameron, is more difficult. Brain scans show that, when men talk, they use almost exclusively the left-hand side of their brains, whereas women also use parts of the right side. But, according to Cameron, this has had no bearing on how we communicate.

The only proven effect of this neurological difference between the sexes, comes in the case of severe head injury. If men suffer an acute injury to the brain, they are more likely to lose their speech faculties than women, because other parts of the female brain are able to take over.

Myth 4: men interrupt more than women The evidence suggests women interrupt as much as men do. Cameron argues that some men, naturally, will interrupt more than others. The dangers of grouping men together is that the differences between men and women are so slight, whereas the differences between men and other men are more interesting.

When, and how people interrupt, argues Cameron, is much more about power and social relations than the genetic make-up of the sexes.

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