Cathal Morrow has set himself the task of going a year without telling lies - but why?

THE COMING WEEKS are set to be challenging ones for Cathal Morrow, who has set himself the task of living for a year without lying. Christmas is a time for questions, and his four-year-old son has already been quizzing him about where exactly Santa lives. "I told him: 'The Father Christmas you believe to be real lives in the North Pole'," says the 43-year-old father of two.

He admits the reply is "a bit of a cheat". But, to his credit, he can cite no more serious a fib since he took his truth-telling pledge eight months ago.

"With kids, it is easy to lie. They say, 'Can I have more biscuits?', and you say 'No, they have all finished', when in fact they haven't. Now, I just say no, and it hasn't really affected them. There's no major drama."

He is right when he says some lies are instinctive. En route to meeting Morrow in Dublin, to which he paid a short visit this week, this reporter walked past a man on the street who asked for change. Immediately, I blurted "sorry, I've nothing on me" and tapped my pocket, where a few coins jingled.

As a former IT recruitment specialist who used to sell websites to hedge-fund managers, Morrow has documented similar, everyday lies in the world of work. "There is a whole philosophy in sales of 'the answer is yes; now, what is the question?' You have to 'close' people and there is manipulation in that."

He says many people justify lying, cheating and stealing in business on the basis that they are "doing it for their families". But, he says, "there is a danger in that, because I believe there are 'high truths', one of them being that we should have respect for everyone, and I don't think we should ever lie to those truths".

Morrow's project has attracted media attention in a number of countries, and on the web, where, ironically, he has been the victim of lying himself.

Last month, he announced that a private equity company - operated by Edward Fitzpatrick who has Tipperary roots - had agreed to fund the writing of a book on Morrow's experiences. He has completed the first 25,000 words, has contrived a title (a somewhat crude pun on the name of the truth-loving philosopher Immanuel Kant), and has published a first excerpt on his website, www.thecompletekant.com.

But a blogger in Asia has been posting claims on the web that it is all a public relations stunt, and that there will be no book. "I think it's funny that I've become a victim myself," says Morrow. "Italy's communist newspaper did a piece on me recently, and it said in the last paragraph: 'There are some reports that the whole thing is a lie'," he laughs

Morrow, whose late father was from Dublin, dislikes comparisons between his project and other works in the "year-long experiment" genre, such as The Year of Living Biblicallyby AJ Jacobs, and Yes Manby Danny Wallace, soon to be a Jim Carrey film. "It's not like a competition for me to hold my breath and then when I tell a lie it's gone. It's much more of a philosophical journey."

His starting point is Kant's claim that it is always morally wrong to tell a lie. Morrow disagrees with Kant to the extent that there are "higher truths" that justify telling the occasional fib. He says the higher truth of protecting human life, for example, would justify telling a Nazi soldier that there were no Jews hiding in your cellar.

"There is a difference between what it is true and what is truth," says Morrow, who claims to be non-religious, or, in his own words, "a pretty rubbish Jew". "What is true is that I am not a Catholic and the kids know that. But what is truth is that the teachings of the Bible that my wife reads to my kids are very beautiful and if they learn those things then I'd be very happy."

Morrow had a difficult relationship with his own father, "a brilliant painter and musician but an alcoholic". Michael Morrow, whose ashes are scattered on Lough Bray in Co Wicklow, had haemophilia and was infected by a contaminated blood product in a health sector controversy that was investigated by the Lindsay tribunal. "His death, which is almost 15 years ago now, had a heavy impact on me. There is part of me that wants to be the same as my father, and there is part of me that wants to be different."

Morrow, whose mother is from an Austrian Jewish background, grew up in the UK and now lives in Spain. Becoming a parent himself was a big motivation in his quest. "You can tell your kids what you like. But in the end they see what you are and then live their lives by that," he says. "If I haven't really a firm grasp about what is truth, how can I teach my kids?"