Saul Bellow, who died on Tuesday, was a realist, a streetwise philosopher who drew on his life and that of his friends. Eileen Battersby recalls meeting the Nobel laureate in Chicago

Greatness sought, greatness won, immortality assured. With the death of Saul Bellow ends a defining moment in US literary and cultural life. A few short weeks ago, his exact contemporary, playwright Arthur Miller, died, leaving Bellow as the sole claimant to the mantle of US literary giant. Now the 1976 Nobel literature laureate, among the most intellectual of US novelists, who never wanted his novels to appear intellectualised, has also taken his leave.

He was a realist, the streetwise philosopher who introduced European angst to snappy, conversational narratives exploring the daily difficulties sandwiched between the drama of being born and the slow process of dying.

There was Jewish humour, despairing eloquence, clever characters bewildered by the messy business of being alive and, as the years passed, aevolving tone of knowing regret. His fiction has energy, a great deal of talk, a masterful amount of nuance. Here was a writer who grasped early in his long career that the enduring genius of American fiction is contained within its dynamic, free-flowing language. Bellow's prose is vivid and physical.

Life's confusion was his art, and his art drew on his life and that of his friends. Bellow made no secret of this habit. Ravelstein, published in 2000, was no exception. In that book, he created Abe Ravelstein, larger than life, a once poor academic made rich by a bestseller. Of that success, the narrator, Ravelstein's old pal, Chick, remarks: "He had gone public with his ideas - difficult but popular - a spirited, intelligent, war-like book, and it had sold and was still selling . . ."

Chick could well be Bellow. But more importantly, Ravelstein was seen as none other than Bellow's friend, critic Allan Bloom. Some critics objected at the blatant highjacking of a life. Still, it is a very fine novel; late Bellow and great.

Here was the clever Jewish boy, a son of emigrant parents who had arrived in Montreal from Latvia, then part of the old Russian empire. Bellow was born in Canada in 1915 but his personality was shaped by Chicago, the city that became his theatre, where his family moved in 1923. His father couldn't read but he was proud of his son's books, while his mother died young, aged 50, and left her clever son angry and hurt.

Few writers made their debut with the assurance of Bellow. He started as he would finish: sharp, almost cryptic and engaged. Dangling Man was published in 1944. It tells the story of a man in limbo, waiting for his call-up papers. It is life suspended and looks to Kafka and even Dostoyevsky. But for Bellow it was the beginning of a lifelong study of alienation as experienced by what he saw as the eternal outsider. His outsider was the Jew in the urban landscape of New York or Chicago, trying to be American despite the burdensome weight of eastern Europe on his psyche. His characters battle with notions of identity, but for Bellow there was never any doubt as to who he was. Bellow was driven by his need to write as well as by a self-belief that protected him from everyone else.

I met him in May 1989 in his office in the Department of Anthropology at the University of Chicago. On the phone, he had been firm.

"Get a cab when you're coming to see me. Strange things happen here . . . it's a violent place," he said, before describing the campus as being bordered on three sides by a black ghetto. Having been thus warned, I wondered what Martin Amis would have done, and decided to travel by bus - more atmospheric.

The university buildings were mock-Gothic and intended to look older than they were. When I arrived at his office door, the "B" of Bellow had become unstuck. He wanted me to know that I should have obeyed his directions about the cab - "but you got here".

I'd like to say he seemed thrilled by my arrival, but he didn't. He was tired; a small, neat little man, hunched. His hands kept moving to his face as if to hold his head. He had brown, hooded eyes, which I'd remembered Amis describing as "like a lizard's". By then, Bellow was 74, his Nobel Prize was 13 years old and he had continued to write, believing that the prize had made things harder for him. He felt the critics were more eager to pounce.

It had come the year after Humboldt's Gift had won the Pulitzer Prize, and Bellow had become the first American to win it since John Steinbeck some 24 years earlier. Two very different writers, two very different Americas. Bellow had a big hollow laugh, and once he made it clear that he preferred conversations to interviews, the interview settled in, being far more fun than merely having an audience with a great man.

Books occupied the room. No pictures, just books.

"I've been married four times, and I still don't understand women," he said. It could have been a line uttered by one of his characters, Bellow having specialised in academics who - when not discussing literature - sound like the rest of us. But Bellow was very clever, an American intellectual capable of taking on the best of the Europeans. His toughness tempered his art. "I write about who we are and why we are here and what this life is all about," he said.

On that day in 1989, Bellow was clear that he did not see himself as a writer with a capital "W". Being a writer meant responsibility, but no guarantees. The more famous you became, he said, the more the critics began searching for flaws. At that time he could look back more than 30 years to The Adventures of Augie March (1953), a loose picaresque featuring a character who had little in common with either Joseph from Dangling Man or the deeply troubled Asa Leventhal of his second novel, The Victim (1947).

Augie March is all America, all mouth and defiance. It was a big book for Bellow, yet one he would leave behind, as his enduring vision asserted itself in works such as the wonderful novella, Seize the Day (1957), with its theme of one man confronting failure, and Herzog (1961), an outstanding portrait of a middle-aged intellectual. At the close of Seize the Day, Tommy Wilhelm stands in a chapel at the funeral of a stranger and bursts into tears. Someone is overheard saying: "It must be somebody real close to carry on so." But Tommy is weeping for himself, as the finest of Bellow's characters invariably do.

Sorrow and hurt are central to his fiction, although there is also life and humour. Therein lies the genius. An abiding humanity gives it an extra dimension.

Time has witnessed the slow maturing of another major US novelist, Philip Roth. Bellow, however, began mature, because he explored his Jewishness in a wider context. Yet he was no saint. He could be ruthless and cruel, as his biographer, James Atlas, made sure to record in his candid biography, published in 2002. It did credit to Bellow the man that he remained on speaking terms with Atlas.

The Dean's December, published in 1982, is set in Bucharest and follows a Chicago college dean to the bedside of his dying mother-in-law. It is a stark book and stands the test of time. It also takes many of Bellow's big themes and places them against the abiding one of failed relationships.

This central theme is at the core of the profoundly touching achievement of More Die of Heartbreak (1986), in which Bellow drew on his philosophical intelligence and his convincing simplicity. An uncle and nephew discuss the nature of life and hit on truths in the middle of the night. The cleverest people do the dumbest things in relationships. More riches were to come with the late novellas, including A Theft and The Bellarosa Connection, both of which he had completed by the time I met him. Even as an old man, he had a slightly unnerving worldly charm. It was as if an illegal poker game was waiting for him in another room. But when he reached for his dapper black fedora as we walked to the train station - with him on the lookout for assassins threatening me, not him - he was old-world courtly solicitude personified.

No, no saint. But a real person; feisty, flawed, funny, as shrewd as a gangster, as lyric as a poet.

"I must be a romantic at heart," he told me, and I guess he was. The novels are there, among the finest in 20th-century US literature.

Then there are the short stories. Death is a major presence, if not quite a theme. In grand Bellow style, his ageing characters look back on the messes they've made, the hurts they've caused, the people who've died. His favourite stock types dominate: troubled male academics with the souls, or at least the vocabularies, of gangsters, not forgetting the cringing guys who made the wrong business deals.

Characterisation may well prove the enduring essence of Bellow's art; sometimes an entire individual emerges through the use of one choice sentence. True, he was a novelist, and his idea of a "short" story was longer than most, but there are great performances, such as What Kind of Day Did You Have? and Leaving The Yellow House.

The world of Bellow's fiction is that of the Jew adrift in the US but intent on becoming American. The prose is physical, his sinners are human and his storytelling lives, breathes and dazzles through its frenetic street-speak and wealth of life-defining moments. There is also his notion of truth, as so brilliantly considered in The Actual (1997).

Saul Bellow has bid farewell, but his books will endure. The Dean's legacy is assured.