As literary duels go, this one could hardly be more gripping. The grand old Marxist of letters, Terry Eagleton, has strapped on his notched side-iron and called out Martin Amis, the fancy gunslinger of the chattering saloons. The OK Corral where they are destined to meet is the university campus that has recently brought them within range of each other.

Eagleton, a 64-year-old intellectual, one of the world’s leading literary theorists, threw down a challenge calculated to inflame his younger adversary. Accusing Amis of Islamophobia for suggesting a clampdown on Muslims, he attacked the novelist’s late father Kingsley as “a racist, antisemitic boor, a drink-sodden, self-hating reviler of women, gays and liberals”. Amis fils, he sneered, “clearly learnt more from him than how to turn a shapely phrase”.

The venue of their showdown is Manchester University, where Eagleton has been professor of cultural theory since 2001. Amis, author of The Rachel Papers, Money and London Fields, took up the post as professor of creative writing at the university last month. The timing of the encounter depends on Eagleton, who splits his life between his home in Dublin, Londonderry (where his wife teaches at Ulster University) and Manchester.

To his friends, Eagleton is a warm, funny man with a twinkly smile who displaced F R Leavis as Britain’s most influential academic critic. To his critics he is “that dreadful Terry Eagleton”, as Prince Charles called him – a butterfly who follows new cultural trends and whose fame owes more to self-promotion than original thinking. His youthful job as an encyclopedia salesman, he once admitted, was his “earliest experience of peddling ideas to the masses, a project which was later to become my full-time occupation”.

Relishing his contradictions, Eagleton was a working-class Catholic who became a don at the heart of the Establishment in Oxford, where he sold revolutionary papers on street corners and held Irish musical evenings at which he performed his own satirical songs.

Many famous names have felt his critical lash. He dismissed Richard Dawkins’s recent book The God Delusion as “a vulgar caricature of religious faith that would make a first-year theology student wince”.

Now Amis “and his ilk” are in his sights. Amis’s offence was his assertion that as the Islamic population grows, “the Muslim community will have to suffer until it gets its house in order”. Shortly before the fifth anniversary of the 9/11 terrorist attacks, the novelist published an essay in which he argued that fundamentalists had won the battle between Islam and Islamism.

In an interview around the same time, Amis suggested “strip-seaching people who look like they’re from the Middle East or from Pakistan”, preventing Muslims from travelling, and possible deportation. To Eagleton such views typify a drift to the right by the “cluster of liberals and leftists” in his circle who “defend western freedom by actively undermining it”.

His platform for his counterblast is the new foreword to his 1991 classic, Ideology: An Introduction. Eagleton’s beef is that no eminent British writer is prepared any longer to question the capitalist wellsprings that he claims give rise to events such as the Iraq war. By his account, the exception was Salman Rushdie, until the novelist changed from “remorseless satirist of the West to cheering on its criminal adventures in Iraq and Afghanistan”.

Eagleton charges that his former Cambridge student, the playwright David Hare, has “caved in to the blandishments of Buckingham Palace . . . moving from radical to reformist”. And the polemicist Christopher Hitchens, “who looked set to become the George Orwell de nos jours, is likely to be remembered as our Evelyn Waugh, having thrown in his lot with Washington’s neocons”. Oof!

Fighting talk, but some detect a mellowing of the former firebrand. He prefers to call himself a socialist these days and defends the study of religion. “There is the old Joycean question of how far you can walk away from something culturally imprinted in you so deeply,” he reflected. Age has not slowed his output of at least one book a year. He has written a novel, and his play about Oscar Wilde, Saint Oscar, was made into a film with Stephen Rea. He once confessed to feeling embarrassment at colleagues’ difficulty in writing: “Instead of finding myself unable to write books, I find myself unable to stop.”

Even to his admirers, Eagleton’s beliefs are hard to pin down. “There is a sense that Terry is the great antitheorist,” said one. “What he works towards is a political criticism that exposes the hollowness and irrelevance of a lot of critical theory.” Eagleton has remarked that he was able to move freely from Catholicism to Marxism “without having to pass through liberalism”.

Like Forrest Gump, he seems to have been present at all the key academic phases of the past 40 years. A third-generation Irish immigrant, he was born in Salford, near Manchester, into a family that was poor and “socially sophisticated enough to be conscious of their inferiority”. Both his grandfathers had been employed in the gasworks and his father, after winning a grammar school place, opted to work in heavy engineering.

Asthmatic and the only boy with a coat at primary school, Eagleton was bullied at a grammar school run by the De La Salle brotherhood and served as an altar boy at the local Carmelite convent, with thoughts of becoming a priest. The Catholic bishop, he recalled in his 2001 memoir The Gatekeeper, had “the walk of a navvy and the face of a wino”. His schoolfellows were “a spindly, stunted, hollow-chested crew, like a chorus line from Les Misérables”.

He won a scholarship to Cambridge despite being yanked out of the entrance exams with the news that his father had died. “I was furious,” he said. “What my father would have wanted was for me to stay on and take the exams.” He arrived at Cambridge as a committed socialist and a member of CND. Although Trinity was a rich college, Eagleton “fitted it like a glove”, according to a contemporary.

While on a visit to Manchester during his first year as an undergraduate, he met Rosemary Galpin, a state-registered nurse working as a health visitor. They married in 1966 and had two children, Dominic and Daniel. The couple divorced in 1976 and he then embarked on a 10-year relationship with Toril Moi, a Norwegian feminist critic. In 1997 he married Willa Murphy, an American academic, with whom he had a son, Oliver.

As an undergraduate Eagleton came under the influence of the leading left-wing critic Raymond Williams, who offered him a research fellowship at Jesus College. Insecure intellectually, he became a heavy drinker before stopping 13 years ago. (“Giving up smoking was much more difficult.”) At high table he encountered only “doddering, quasi-fascistic clergymen, who talked of Gladstone’s Irish home rule bill as though it could still be headed off”.

So he took a job at Oxford, which was “rather like taking refuge from insincerity in Hollywood”. It took 22 years at Oxford until he was deemed safe. “My strategy for survival was to put distance between myself and the Oxford establishment.”

Whereas Eagleton preferred to focus on the relationship between literature and the culture from which it grows, English teaching at Oxford had been based on textual analysis. His weekly seminars, a focus for dissidents, increased suspicions. “They thought it was a threat to all they held precious. But I think the students I taught found it enormously enriching.” One recalled: “He was very charismatic and used to bang on about the class war. He was embedded in a previous age.”

Tariq Ali, a friend of more than 30 years, says he led a double existence. “He was one of the lads in the pub with the comrades and was wonderfully good at singing and writing songs. But then he’d go off and be a cult literary theorist. To his credit, he always tried to bring his worlds together.”

His star rose throughout the 1970s. “The left was in the ascendant and there was a sense we might break through,” he believed. The publication in 1983 of his most famous book, Literary Theory: An Introduction, made him an international star. Finally in 1991 the dons relented and made him Warton professor of English literature in succession to John Bayley. Typically, his enemies noted, he slagged off Bayley in his inaugural lecture.

Eagleton used to be known as the closest thing to the Sex Pistols in British scholarship. With his attack on Amis he proves he can still spit with the best of them.

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