IN 1993, I went to New York to interview Philip Roth. The excuse was the publication of Operation Shylock, one of the author's lesser-known and less appreciated novels. It was March and snow fell in clumps, bringing gridlock to the city. We had arranged to meet mid-morning at a diner on the Upper East Side. The hotel in which I was staying was on the opposite side of Central Park and, as the minutes ticked away and my cab made little headway amid the honking traffic, I decided I would be quicker on foot.

This proved not to be a smart move, as I waded across the park through snowdrifts while others used skis. Nevertheless, I made the appointment just minutes late, albeit sodden. Roth was not amused and for the first few minutes the interview progressed in fits and starts. Eventually, though, he defrosted and when we said our goodbyes he mentioned he was going that evening to a school reunion in Newark, New Jersey, where he grew up.

Was it then he got the inspiration for American Pastoral, or was the idea for it already percolating in his subconscious? Who but Roth knows? But what is now clear is that from virtually that point on he seemed regenerated, producing in metronomic succession over the past decade a series of pugnacious novels . . . I Married a Communist, The Human Stain, The Plot Against America . . . that went straight to the solar plexus of America.

Now Roth, who is 74, is revered as one of America's greatest living writers, his oeuvre collected in the prestigious Library Of America series, an accolade afforded to few of the living, his name monotonously associated with the Nobel Prize. He is also said to be reclusive. How true this is I'm not sure.

With him myths grow and mushroom, often with little basis in fact.

Often, as Roth himself wearies of pointing out, their genesis lies in his fiction, in which characters whose lives seem to mirror their creator's abound.

The most famous of these is Nathan Zuckerman, a character who makes his ninth appearance in Exit Ghost. The novel's title is an obvious echo of The Ghost Writer, in which Zuckerman had his debut. Then, he was a rookie writer, in awe of EI Lonoff, a shortstory writer in the mould of Isaac Bashevis Singer. Lonoff, however, is long dead and Zuckerman is ageing with Roth. It is 2004 and the eve of the election that will see George Bush jnr confirmed in the White House for a second term.

For the past 11 years, Zuckerman has been living alone in New England, writing constantly, urgently, as if in a race against time, rereading the classics, seeing only those people he needs to, his health increasingly poor. As a result of prostate cancer, he is incontinent and impotent. He has come to New York, we learn, to consult a urologist who, hopes Zuckerman, can do something about him wetting himself.

Seen through his out-of-towner, septuagenarian eyes, New York has changed and not for the better.

Brought up in "the era of the telephone booth", he is bemused by the ubiquity of cellphones. Everywhere he goes people are talking on them. Zuckerman, who thinks he can still make collect calls, considers writing a story in which Manhattan has become a "sinister collective where everyone is spying on everyone else". It is a city in flux, as it always was, but post-9/11 there are more people leaving than arriving. Zuckerman, who knew it in its bitchy, intellectual heyday, the 1940s and 1950s, remembers a New York "when the only people walking up Broadway seemingly talking to themselves were crazy".

This, then, is Exit Ghost's clamorous backdrop. Much against his better judgement Zuckerman is sucked back into New York, first . . . and principally . . . by an infatuation with a young woman, Jamie Logan, one half of a couple with whom he agrees to swap houses. "She had a huge pull on me, a huge gravitational pull on the ghost of my desire, " he reflects.

"This woman was in me before she even appeared."

Zuckerman is confounded by his lust, all the more so perhaps because it cannot be consummated or reciprocated. Jamie, as an aspiring writer, may look up to him but she is not about to cheat on her doting husband for him.

But there's nothing preposterous or unrealistic about Zuckerman's feelings. On the contrary they are all too believable and affecting. Old men are just as susceptible as young ones to the vagaries of passion, however silly they make them look.

Meanwhile, other ghosts are surfacing. In a luncheonette, Zuckerman spots Amy Bellette, last seen in The Ghost Writer bearing "some resemblance to Anne Frank". Ballette's beauty has faded, precipitated by a brain tumour.

She was 27 when she and Zuckerman first met at EI Lonoff's. Subsequently, she became the great man's lover and partner. Over the days that follow she and Zuckerman will delve into their overlapping pasts, exchanging memories of Lonoff, whose reputation has waned since his death. Ostensibly on a mission to rescue it is Richard Kliman, a freelance journalist and former lover of Jamie, who wants to write Lonoff's biography. Both Ballette and Zuckerman, however, believe he is a muckraker out to dish up dirt using Lonoff 's novels as evidence.

"So, " Zuckerman tells him, "you're going to redeem Lonoff 's reputation as a writer by ruining it as a man. Replace the genius of the genius with the secret of the genius. Rehabilitation by disgrace."

Can't Kliman, can't anyone, tell the difference between fact and fiction any more? It's an issue that has plagued Roth ever since the publication of Portnoy's Complaint in 1969. In the intervening years, the notion that novels and other works of art can be read and judged only with reference to their creator's personal story has polluted the media and academia.

Now, everything must be autobiographical and nothing can exist on its own merit. It is, as Roth and Zuckerman insist, the laziest, most unilluminating form of criticism.

In Exit Ghost, however, the most eloquent expression of this dismay comes from Ballette, in a letter rejected by the New York Times.

"Your cultural journalism is tabloid gossip disguised as an interest in the arts: and everything that it touches is contracted into what it is not. Who is the celebrity, what is the price, what is the scandal?" Hereabouts her argument, and Zuckerman's . . . and Roth's . . . may be boiled down to two words: dumbing down. Only the most ostrich-inclined philistine would argue that they . . . and he . . . are wrong.

But to reduce Exit Ghost to a debate of this nature would be misleading. Whatever else Roth is, he is not interested in using his fiction to settle scores or win fights.

How wasteful of his energy and his art that would be. His intent, in this novel and the others involving Zuckerman, is to show what a writer's life entails. What it costs.

What its consequences are. How it impacts on others. The isolation.

The struggle. The sheer graft. The pain. It ought to be required reading in every creative writing class.

It's why Roth is a writer's writer, and one for intelligent readers too.