The author who finds himself in his own Catch-22

Portrait of an Artist,as an Old Man by Joseph Heller (Scribner, £12.99)

In the 1970s, the American literary journal Tri-Quarterly was the parish noticeboard of the new "fabulism". There, Philip Stevick published an influential essay called "Scheherazade runs out of stories, carries on speaking; the King, intrigued, listens". Stevick battled it out with an old-fashioned conception of fiction as a repository of moral and psychological truth. He argued that it was the act of fabulation itself, the author's musing voice, which made fiction compelling.

In the 1970s, the American literary journal Tri-Quarterly was the parish noticeboard of the new "fabulism". There, Philip Stevick published an influential essay called "Scheherazade runs out of stories, carries on speaking; the King, intrigued, listens". Stevick battled it out with an old-fashioned conception of fiction as a repository of moral and psychological truth. He argued that it was the act of fabulation itself, the author's musing voice, which made fiction compelling.

Joseph Heller's final, posthumous novel borrows from a classic, so let me do the same: "The creator of Catch-22 runs out of stories, continues writing; his admirers, horribly fascinated, squirm in embarrassment, but stick it out to the end."

It would be easy to be put off by the early pages of this strange book, which requires a certain suspension of irritation. Heller's persona is the novelist Eugene Pota, once successful, once a charmer, but now blocked and creaky, desperate to write one last remarkable book - something that will stop the frequent complaint that he peaked early and declined rapidly.

We sit side by side with Pota - an acronym of "portrait of the artist" - as he starts and abandons, by turns, the story of Tom Sawyer after Huck's disappearance; a fantasy based on the story of Zeus and Hera; the hypochondriac fantasy A Pain in the Neck; and something to be called A Sexual Biography of My Wife.

All this is "intertextual" with a vengeance. The hypochondriac book needs that title because The Anatomy Lesson has already been done, most obviously by Pota's near-contemporary Philip Roth. The faulty memory is reminiscent of the amnesiac hero of Mordecai Richler's novel, Barney's Version. The problem with Pota - and with the book - is that he stops endlessly, restarts and stops, hesitates, crumples and then restarts again.

In this, it is exactly in the line of Heller's earlier, supposedly better work. Catch-22 was "about" war, but far more profoundly about missed communication and impossible love. Heller's real masterpiece, the follow-up Something Happened, was about essentially the same things: closed doors, the unsaid, and the casual destruction of one's own creation. God Knows had the same all-round-the houses rhetoric, and wilful belittlement of anything grand. Here, though, the theme is almost unbearably naked.

Pota inevitably finds himself in catch-22 situations. The centrepiece of the novel is a rambling lecture on that old Scott Fitzgerald theme about there being no second acts in American lives. With a mixture of self-satisfaction and schadenfreude, Pota lectures on the fates that befell Tom Sawyer's creator Samuel Clemens (bankruptcy, dead children, melancholia), Jack London (alcoholism), Fitzgerald (ditto), Hemingway (ditto plus), and a horde of other damaged and self-destructive literary creators. Like any other old geezer whose greatest comfort is the obituary page he has not yet graced, Pota's vital signs are calibrated to the fates of others.

The drafts he attempts are embarrassingly inept. If it's true that the one thing no writer can ever create is an artist greater than himself, then it's twice as hard deliberately to write badly: a little like asking a concert pianist to fluff. At best an edgy enterprise, this is likely to lose readers, but the sheer persistence of the book's central consciousness holds it together. Though the final pay-off ("and he began to think seriously of writing the book you've just read") is telegraphed from the start, there is more to this than playful self-reference and veiled autobiography.

Portrait of an Artist as an Old Man is a wise, funny, painful account of a life spent on the hardest frontier of all, which is why we, just like that old mythical king of Persia (or was it Arabia?), keep on listening.