AT A RECENT school coffee morning a fellow mother asked a startling question. “Am I wrong to be teaching my kids to be honest?” she asked. “Will I be stopping them from making their way in the world?” This was electrifying. Are we so much more mendacious these days that dissembling should now feature as a life skill on the curriculum?

This woman is no sheltered soul. She has had a high-powered business career. She has seen how people tell small lies and how others increasingly cave in to them. She once monitored the refund counter of a supermarket. People would demand refunds, with no receipt, for goods that the store had not stocked for a while. But the staff often paid up. They didn’t want a row. They assumed that people were dishonest, and they didn’t seem that bothered about it.

When did we start expecting people to lie? We have passed a tipping point into a world that is full of professional dissemblers. Marketeers, public relations people, lawyers, some campaigners, and an ever-changing cast of “customer service reps” who promise to ring you back, promise to wipe the charge off your bill but actually erase all traces of your conversation so that the next time you will be treated as prime suspect in some surreal game of cat and mouse in which suddenly everything is your fault. Lying is a growth industry in which it often seems more important to blame, complicate and confuse than simply to fix the damned broadband connection.

Our cynicism has peculiar consequences. The widespread assumption that politicians are liars makes some journalists imagine cover-ups even to the point of trying to manufacture them, while they can seem strangely blasé when real lies are exposed. So desperate were the tabloids to keep alive the self-serving media storm about David Cameron this weekend that they printed a photo they had owned for at least five months but had not used, because they knew the “story” was thinner than a Rizla paper. The student photo of George Osborne, MP, in a tie merely made him look too square to have been up to no good. Mr Osborne was duly exposed — but only as a man who had tried to save a friend from drugs and from a woman who has clearly found editors as willing as she is to exaggerate the actualité.

What we might call a Class A lie told by Stephen Byers, the former Transport Secretary, has generated less indignation. Taken to court by Railtrack shareholders who accuse the Government of robbing them by forcing the company’s collapse, Mr Byers admitted that he had been “untruthful” with MPs about the date when he began drawing up plans to junk Railtrack and make himself the Fat Controller. But is any journalist investigating which mind-altering substance caused Mr Byers to lose track of time?

Most fascinating is the new definition of truth and untruth given to us by Mr Justice Lindsay, who found in the High Court on Friday that Mr Byers was not a “proven liar”, despite his admitting lying to Parliament. “He accepted to me that he told an untruth. But that, of itself, does not brand him a liar, if a liar is someone who tells an untruth knowing it is untrue or being reckless as to its truth or falsity. Whether he was a liar within that meaning is not for me; I must leave it to the House of Commons.” So the Standards and Privileges Committee becomes the final arbiter of truth; and MPs may take a dim view of Mr Byers’s statement this week in which he apologised for what he has downgraded to an “inadvertent error”.

It is human nature to make finely graded distinctions between different shades of dishonesty. There is a hierarchy of lies, from white lies up. The problem is that real lying is generally regarded as what other people do: Enron or UN Oil-for-food officials or Jacques Chirac, who claimed £100 a day for fruit and veg. There is quite a different mental category for you fiddling your expenses, taking a “duvet day” or challenging that parking ticket because you think you might get away with it. Those things do still seem a bit dishonest to most of us. But isn’t honesty beginning to feel old-fashioned, even a bit naive, when everyone else is on the take? A widespread view, but one that is seriously corrosive.

A survey this year found that one in four British students admitted to copying and pasting material from the internet and then presenting it as their own. As striking as the lie is the students’ brutal honesty about it. Nearly one in five said that they saw plagiarism as an acceptable practice. Yet universities are strangely embarrassed to take a tough moral line on cheating. The Britain where “courtesy pressure groups” try to restore manners also has a Plagiarism Advisory Service that is busy “identifying examples of best practice”. Why not just say that plagiarism is wrong, and stop making polite excuses?

The truth is perhaps that we no longer value honesty as much as we did, but we still value the appearance of honesty. We draw far too great a distinction between corruption, which still provokes an indignant intake of breath, and cheating, which we increasingly seem to think comes with the territory as long as you can get away with it. Firms are hiring psychologists and recruitment advisers to probe CVs that they can no longer trust. And the fact that people more readily admit to cheating is a sure sign of its moral downgrading.

It is not inevitable that a flirtation with Class C untruths will tempt fibbers into telling Class A lies. But condoning cheating, as the universities and the supermarket staff seem to do, can surely only fuel the impression that everyone else is on the make. The University of Virginia has found falsehoods told in a fifth of all ten-minute conversations, rising to a third among graduates. If education gives people the confidence to deceive, we will have to work extra hard to keep our children honest.

camilla.cavendish@thetimes.co.uk

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