Top of a recent Observer non-fiction bestseller list was Purple Ronnie's Little Book for a Smashing Grandad, sequel to his ditto for a Smashing Dad. Ronnie's commercial imperative is clear from his titles. But fans will be pleased to know that he displaced Cherie Blair's autobiography, which first fell to fourth place, and then, last week, disappeared from the top 10. Ronnie meanwhile has shifted 16,400 copies.
These numbers alone are a forlorn index of the recent decline of book sales in general, non-fiction in particular. To be the subject of a non-fiction bestseller these days, you have to be less an object of literate adult interest than a showbiz or sports star abused in childhood and married in Hello! magazine. Narrow the genre down to autobiography, and you have to be a former prime minister's wife prepared to spill the beans on their mating habits. Make that biography, and you're not going to make the list.
What does this tell us about the reading public? That its attention span is slipping? Or simply that tastes have changed? Before being seduced by the cult of celebrity, the 20th century proved a golden age of biography; now it is hard to scan those lists without reading its last rites.
As a "popular" biographer, writing less for academe than the general reader, I have in my time received six-figure sums for studies of the living (the Prince of Wales, when he was interesting) and the dead (Shakespeare, always interesting).
After some 20 such books, however, I must now turn my non-fiction sights elsewhere. Even the likes of Michael Holroyd and Antonia Fraser, loftier deans of our craft, are seen by publishers as high-end loss-leaders for their lists, and will soon have to come up with new letters or diaries to justify yet another journey down some well-worn path.
That's another of the problems. Given the century-long vogue for biography, everyone worth "doing" has been "done". Public figures, from politicians to TV, rock and sports stars, these days "do" themselves, if with the help of a ghost writer – often, as in the case of Cherie, invading their own privacy with details inadmissible from anyone else.
In recent years, with my children grown and less pressing need for large advances, I have enjoyed the freedom to write books I have long yearned to – on less well-known and so less lucrative subjects who led fascinating, useful lives, from the Romantic poet Leigh Hunt to Mozart's librettist Lorenzo da Ponte. Even so, as with every subject I have ever tackled, someone else was simultaneously on the case.
Not any more. Soon few will be on any cases, except the subjects themselves, not usually writers. One of this autumn's bestsellers will be Sean Connery's autobiography Being A Scot; another could be Cameron on Cameron, an insight into the Tory leader by Dylan Jones, whose previous books have included studies of pop music and male etiquette.
You could argue that the craft of "life-writing" has wrought its own decline, by growing increasingly sensational to meet the commercial demands not just of publishers, but of the "carriage trade" (high-street bookshops, from Waterstone's to the few remaining independents) as much as Amazon and that major new force in bookselling, Tesco. As their buyers divined a drop in the demand for conventional, chronological, "doorstop" biographies, there came a vogue for much thinner "slices of life", zeroing in on one significant episode. Victoria Glendinning's biography of Swift, for instance, revolves around the two significant women in his life. David Starkey's Elizabeth I, billed as a comprehensive life of the Virgin Queen, stops when she ascends the throne. Nicholas Roe's rival study of my own dear Leigh Hunt stops halfway through his life, with the death of his friend Shelley in 1822, when my own 430-page biography still has 244 to go.
I protest less as a writer than as a reader. Spending several years living someone else's life, shoe-horning hard-earned facts into a supposedly compelling narrative, is a poor alternative to living one's own. I look forward to devising new non-fictional challenges for myself, beyond poker (my new cottage industry, after banishing the royals) and my onerous duties as the Observer's music critic. But I much enjoy reading biographies, and lament the fact that there will soon be far fewer to choose from.
If biography as we know it began in 1763, when 22-year-old James Boswell walked into a London bookshop and met a 53-year-old Samuel Johnson, the question now arises: would Boswell's Johnson find a publisher today? As Holroyd has pointed out, a 21st Century editor would probably tell him: "Forget the first 53 years of Johnson's life, and begin at that London bookshop where you met." At a time when it is more cost-effective for publishers to pay an author the full advance, but lay off editors and cancel publication, would Lytton Strachey's Eminent Victorians make the cut? This was the prototype of the debunking, warts-and-all biography, which so long satisfied a voracious public appetite, but has now been displaced by overgrown versions of glossy magazine profiles.
There was a time when writers themselves were celebrities, ripe for plucking by those Joyce called "biogra-fiends", often so desperate to avoid it as to destroy their letters and other papers (Freud, Hardy, Henry James) or instruct their executors to withhold cooperation (Kafka, Eliot, Orwell). These days, Nobel laureate VS Naipaul sanctions a book detailing his serial maltreatment of women, and itemising his snobbish vanity. Does this, as in the case of the racist, sexist Philip Larkin revealed by Andrew Motion affect the way we read their novels or poetry? Of course it does, even if it shouldn't.
This is but one of many vexed debates we could have about the ethics of modern biography. But there'll soon be no point, alas, now that public demand is dictated by those who buy their books with their groceries.
