OK, gloves off, this week I'm going to talk dirty. I mean really dirty, one of those subjects which simply isn't discussed in polite society. Novelists are obsessed by it, but even they struggle to find a vocabulary acceptable to their readers - and mostly give up in despair. Sex, by comparison is a doddle; what I am addressing is the last big taboo, more unspoken than death, which causes big intakes of breath on the rare occasions it gets mentioned in public. I am talking, of course, about money. Authors and money, to be precise, and the nitty-gritty of how much they get paid.

Or, more to the point, how little - and how most of them are too demoralised, or too afraid of the effect on their careers, to discuss it openly. This is, at first sight, an odd state of affairs, given the kind of world we live in. Most people worry endlessly about their rent, their mortgage, their gas bills, whether their pension is going to be large enough in 20 years' time - assuming, that is, they can afford to accumulate one.

Why writers are supposed to be immune from these anxieties is something I have never understood, although it must be in part because the old English reticence about finance is so entrenched. This is true even among people who talk freely about their most intimate relationships and bodily functions; the Princess of Wales, who was a veritable pioneer of our confessional culture, drew a discreet veil over her bank balance and her divorce settlement. Far more acceptable to admit to bulimia and adultery than the amount of money she wanted from Prince Charles, for the prohibition on women talking about money is particularly potent

This is true even if you earn every penny yourself, have never been supported by anyone and don't expect handouts from the state. During a writers' conference at Warwick University two weeks ago, there was a palpable reluctance on the part of the audience to talk about the day-to-day problems most authors face. Everyone in the industry knows that millionaire novelists such as Jeffrey Archer are the exception, yet no one wants to admit to the depressing struggle to finish manuscripts long after paltry advances have run out or confront the reasons behind it.

One of these is the widespread perception that writing is not really a proper job, yet at the same time extraordinarily well rewarded. The unglamorous truth is that, for the vast majority of us, it isn't. When writers gather together, whether they are novelists or biographers or essayists, their talk is usually about how on earth they are going to live while they finish their latest book - or, as a friend confided to me in a panic on Friday morning, how she is going to rescue an entire chapter from her ancient, malfunctioning computer. Why is she working on such an old machine? Because, even though she has won prizes for her earlier books, she does not earn enough to buy a new one.

Such stories, in private, are legion. And they are directly related to the way in which publishing, which is an increasingly ruthless industry, likes to pretend there is no relation - for authors at least - between work and money. When a leading literary imprint, Hamish Hamilton, approached me in January to write a book about contemporary culture and politics, I threw myself into producing a series of ever-longer synopses, at the editor's request, only to discover from my literary agent in May that he expected me to write the book for an initial payment of less than pounds 5,000.

Even with my income from journalism, this is hardly a viable proposition. But the truly perplexing question is why a publishing house would expect a professional author to spend a year writing a book for so little money. When I posed this question to a senior figure at Penguin, which owns Hamish Hamilton, she told me she could not possibly think about how authors live, as though I had just made an extremely indecent proposal. She also admitted that Penguin is fortunate because so many writers are willing to depend on other sources of income - the frankest admission to date that publishers expect authors to subsidise their companies.

This is bad news for those of us who don't want to rely on the old stand- bys: rich parents, trust funds, other full-time jobs, generous spouses. It is also bad for readers, because it is already having dire effects on who and what gets published - television tie-ins, unreadable novels by celebrities, endless drivel about Princess Diana. I just wish more writers were prepared to stand up in public and get angry about it.

THE Guardian, which suggested my most recent book should be pulped because it was insufficiently respectful to the late Princess, picked up last weekend on my remarks at Warwick. It also quoted an essay I wrote earlier this year, affecting astonishment that a full-time writer should aspire to live in a house and have a social life. This goes a long way to explain why authors are so reticent about money, fearing the accusation of "greedy writer" - or even worse, "greedy woman writer". I would feel crosser about this if I wasn't aware of a little-known fact, which several of the Guardian's journalists have confided to me, strictly in private. Apparently it is a condition of employment on the books pages that the staff live together in a mobile home, parked just off the Farringdon Road. That's why they are a little - how shall I put it? - sensitive on the subject of other people's accommodation.

AS it happens, I have an idea for a book which would almost certainly be a best-seller. The Little Book of Blair would be a collection of the Leader's sayings, including the moving tributes he has paid to those towering figures of our age who have had the misfortune to pass on in the last year: Frank Sinatra, Linda McCartney, Sir David English. Mr Blair's pronouncements on the recently deceased have become so frequent that a friend, active in Labour politics, told me last week that he is having a little card printed. "In case of my death," it states simply, "I do not wish to receive a tribute from Tony Blair or any other member of the present government."