If, felled by the cold, the wet, the dreary, you are looking for an excuse this winter for a spell of rampant misanthropy, this is it. Radical Honesty. It will change your life. It will change your life in the same way that a car crash will change your life, say its critics. And it’s true that there are people who emerge from the catastrophic events in their lives and think, yes, now that my former existence has been annihilated, my life is so much better. These people exist. So it is with Radical Honesty.

The premise is simple. Radical Honesty is like a deliberate form of autism. Whatever comes in to your head, put it out there (the word “autism” just then, for example. I had second thoughts on account of all the angry letters autism societies are now going to have to send me because of my contextually inappropriate reference to a chronic medical condition, but in the name of Radical Honesty I decided to leave it in).

Tell the truth, never mind if whatever the truth turns out to be is potentially hurtful, bigoted, character-assassinating or career-or relationship-ending. That means: Yes, your bum looks big in that. No, I’ve never been faithful. And while we’re on the subject, you know when I say “Of course I’m listening, I just look as if I’m asleep”, the truth is that I’m not listening. To be absolutely transparently candid for the first time – what a relief it is to finally get this off my chest – the reason I’m not listening is because, if I did listen, if I did have to fully digest the stream of relentless drivel that ushers from your mouth every day, I would have no choice but to file for divorce and I’m too much of a coward for that.

There are couples that bitter. Sometimes they end up at Brad Blanton’s Radical Honesty workshops in Virginia, in which they confront each other with the radical truth. One tape I watched showed a former husband and wife confront each other postdivorce after the husband left the wife for another woman: “I resent you for saying, ‘I love you, Maria, but I’m not in love with you’,” says the wife. “And I resent you for saying no on the phone when I asked you, ‘Did you have sex with her?’ And you said no. I resent you for saying, ‘I never really wanted to marry you!’ ” The voice-over interrupts and soothingly explains: “The workshop promises that by being this open and truthful, you will start having better relationships with people.”

The camera pans from angry Maria to consternated Jeff. How did Jeff get dragged into this, one wonders. Jeff is Maria’s former husband and now it’s his turn to let it all hang out. He summons his will. It’s interesting what ends up driving a happy couple apart. Finally, Jeff lets Maria have it. “I resent you for your nose,” he says.

The architect of this decimating candour is the Gestalt therapist Brad Blanton, 64, genial, outspoken, “white trash with a PHD”, he says. I never got to meet Brad. Instead we talked several times on the phone and corresponded by e-mail. Brad’s first e-mail to me read: “Go to the website, read the excerpts from the book, read the past e-zines (one included here). Do your homework and then get in touch with me. Thanks. Brad Blanton.”

To be frank, Brad is not the most successful of people. His string of self-published books have sold well but he’s no M. Scott Peck. His website is a mess. He ran for Congress twice but was batted away by the powers that be when it emerged that he ran naked group workshops. It’s standard Gestalist stuff, if a bit too starkly reminiscent of 1970s California. For the record, Brad is on his fourth wife – a Swedish stewardess – and has in his life slept with more than 500 women and about a half a dozen men.

When, as a joke, a journalist once asked him “Animals?” Brad said: “I let my dog lick my dick once.” Which admittedly sounds bad. But is it worse than lying? When I told a promiscuous friend about the Radical Honesty concept, his face contracted in to a frown of displeasure.

“I have nightmares in which I’m forced to be honest, and suddenly the whole pack of cards falls down and I have to stop sleeping with lots of girls because they’ll all know about each other,” he said. My promiscuous friend is married and holds down a career as a successful lawyer – and all because he’s compulsively dishonest.

Mightn’t Radical Honesty get in the way of one’s career, Brad?

“Sure,” he says, and he tells me about how, as a psychotherapist working in Washington DC for 30 years, he saw a lot of “screwed up people and most of them were lawyers. They were lying all the time – your garden-variety neurotics.” He says that those wanting to climb to the top of the slippery corporate pole are “probably so sick they’re unrescuable”. Brad’s favourite motto is: anything worth doing is worth doing poorly. “It’s an antidote to that perfectionism, what you learn in conventional schooling is that our performance and how we rate in the eyes of other people is what we are.” Brad’s other unconventional thoughts on life include: “Moralism is a disease we all have”; “Respect for authority is one of the great bullshit traditions”; and “People say that politeness is another form of friendliness but most of the time it’s a form of bullshit.” I point out that the British pride themselves on their politeness and Brad says: “It seems to me that they’re just as f***** up as they are in America.”

Brad’s point is that lying creates distances in relationships and only the truth can heal. Are there instances when it is permissible to lie?

“I advocate never lying in personal relationships,” says Brad. “But if you have Anne Frank in your attic and a Nazi knocks on the door, lie . . . I lie to any government official. I lie to the IRS on principal. If you are involved in the criminal justice system, lie.”

How about diplomacy? Diplomacy is necessary in many human interactions, isn’t it?

“Bullshit,” says Brad. Hyperbole?

“Bullshit.”

How about plain old kindness? “The relationship remains in your manipulative control. You have relationships where couples are just playing a role for 30 years and end up in a bad hillbilly song about ‘Why don’t you love me like you used to do’.” Brad thinks, perhaps pessimistically, that: “Of the 25 per cent of people who stay married my guess is that maybe half are passive, intellectual space-cadet compromises of the sort that make up your standard middle-class survival system: the socially dysfunctional family.”

How about optimism? What’s wrong with a little optimism? I think of my mother, who is in the habit of saying “If you can’t think of anything positive to say, don’t say anything at all.” What would you say to that, Brad?

“Trying to be positive is one of the phoniest things a person can tell you to do. Just start telling the truth, and see what happens. I would say to her that I thought she was full of shit. If she said kiss my ass, you bastard, I’d say congratulations, now we’re getting somewhere.” Somehow I don’t think I can say “you’re full of shit” to my own mother. And if I did I can’t imagine her retaliating by telling me to “kiss my ass.” She’s German and it would sound strange. I don’t think I would want a mother who relentlessly pointed out my defects all day, anyway.

I don’t want to mislead the reader here and imply that Radical Honesty is a mass-movement about to take over the world. The reason it’s here in the paper today is because of the effect the subject had in the office. Every time the subject was raised in front of a colleague I’d watch as his or her gaze crashed guiltily to the floor. It made me wonder just what kind of two-timing double-crossers The Timesoffices are full of.

“What you should do is try to be radically honest over the weekend and then write about it,” said my boss.

“I already am quite honest,” I said. “I don’t think it will make that much difference.”

My boss and a commissioning editor concurred that this was true. “It’s the Germans,” said the commissioning editor. “Germans can be so rude.”

We segued in to a conversation about the au pair who refused the boss’s Christmas present on account of her not liking it. “She was German,” said my boss. “But she was honest.”

Central Europeans are radically honest. So, too, are Balkans and Eastern Europeans. I remember my friend the Bosnian telling me over dinner: “That necklace makes you look like a whore,” and how surprised he was when I asked for the bill and left. I remember the Russian who ostentatiously snubbed me at a party because I’d never fulfilled my promise to “go to the cinema together some day”. My Indian newsagent told me so many times every morning that I looked “very, very tired. Or sick maybe?” that I switched to the guy across the road, a Pakistani who assails me with more neutral subjects such as how to undermine Ken Livingstone by systematic fare dodging. My quest for Radical Honesty would have to begin with somebody from a culture that pivoted on politeness, diplomacy and hyperbole.

“I am a glass half-full person but you don’t want to know what’s going on in my head,” says a British friend of mine whom I have known since I was 12.

“What is going on in your head?” “You don’t want to know.” “For the purposes of this piece can you tell me?”

“Er,” she makes a palpable effort to squeeze the truth to the surface. “You need to get rid of that jumper?” (she doesn’t tell me this, she asks me).

“You don’t like my jumper?” “Er, why are you doing this to me? No,” she blurts. “It makes you look – sorry – about 40, as if you’re working at a pet shop or something, and you chose something the colour of hamsters. And you’re only 35.”

“Thirty-three. Thirty-four in December. My jumper is hamster-coloured?”

“I’m loving your earrings, though,” she says quickly. “Did you get them in India?”

Normally at this point I would have allowed myself to be diverted into a conversation about my disastrous trip to Gujarat. But with Brad in mind, I stayed focused: “You don’t have to compliment me on my earrings to make up for having dissed my jumper.” For good measure I added: “I think you should stop using the present continuous. It makes you sound faddish and unintelligent,” but then I saw her face and felt guilty for having ruined her day. I’m still waiting for us to feel bonded.

(Luckily my friend is good-looking. If she had been ugly I would have had to say, as Blanton suggests, “I think you look kind of ugly and this is what I think is ugly. I think that big wart on the left side of your face is probably something that puts people off and that you don’t have much of a love life. Is that true?”) I bump into another friend on the street. I haven’t seen her for a year.

“You look well,” she says. I notice that she looks like hell.

I steel myself. “You look older,” I say, truthfully.

“My mother died,” she says. “That’ll explain it,” I say. “Want a coffee?”

The radical honesty concept is not all bad and, warming to my theme, I tell a male friend at the pub that night that I think he’s an alcoholic.

“Probably,” he says. “But is it any of your business?”

When a cab driver tries to rip me off on the way home I say: “I resent you for having taken me down Oxford Street when you knew there’d be traffic and you could have gone along the Marylebone Road instead.”

“Sorry I haven’t got the microphone on, love,” he says. “Come again?”

But I’ve clocked the tattoos on the back of his hands and chickened out. “Nothing,” I say. “It’s just here on the left.” And spend the rest of the evening feeling resentful for the £28.20 cab bill.

Finally, it’s Sunday. The last day of Radical Honesty.

My friend G tells me what a “hilarious” time he’s had with his nephew in the park. Brad would say that this statement absolutely reeks of hyperbole.

“What’s your definition of hilarious?” I say. “Covering your kid with leaves in autumn is a standard trick. All parents do it. It’s quite fun. But it’s not hilarious. Hilarious means side-splitting. Were you splitting your sides?”

“Are you having a sense of humour failure?” says G. “For fuck’s sake, it was a light-hearted anecdote. It’s called making conversation.” He hangs up the phone.

And I remember Noah, a case study in Brad’s book, The Truthtellers. “Within three months of the workshop I lost half my friends,” Noah writes. “I alienated my family, had a nuclear blowout with my parents and my whole life turned upside down.”

Sounds tempting, Noah. Right now I’ll stick to Partial Honesty with a Teutonic bombshell thrown on.

The plain speakers . . .

If your lifeguard duties were as good as your singing, a lot of people would be drowning
SIMON COWELL

Mirror, mirror on the wall, who’s the dumbest of you all?
ANNE ROBINSON

Could you expect me to rejoice in the inferiority of your circumstances?
MR DARCY (to Elizabeth Bennet, to whom he has proposed)

You can’t have been here that long. You haven’t got a pot belly.
PRINCE PHILIP (to a Briton in Hungary)

He is a remarkable man. A remarkable servant to his country. And that is the truth
TONY BLAIR (on Gordon Brown)

“Yoroshiku onegaishimasu” means pleased to meet you but is literally translated as “I humbly ask you to be kind to me”
THE JAPANESE

Removed! It must not be thought of. My sister, I am sure, will not hear of her removal!
MR BINGLEY (about Jane Bennet’s prolonged stay, which his sister hates)

I admired her and respected her
THE QUEEN (on Diana, Princess of Wales)

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