Iain Pears: 'It is the civilised who are truly barbaric'

A small boy opens the door, looking rather pale. I'm told he has just had his tonsils out, and when I patronisingly praise him for being brave, he regards me with suitably intellectual weariness. This is the scholarly Oxford household of lain Pears, art historian and novelist, and his wife Ruth Harris, university lecturer and author of a well-respected book on Lourdes.

A small boy opens the door, looking rather pale. I'm told he has just had his tonsils out, and when I patronisingly praise him for being brave, he regards me with suitably intellectual weariness. This is the scholarly Oxford household of lain Pears, art historian and novelist, and his wife Ruth Harris, university lecturer and author of a well-respected book on Lourdes.

Banish all thoughts of Iris-and-John domestic squalor, however. It's an elegant home, furnished with the taste of the trained eye: a light airy sitting-room, 18th-century French chairs, re-covered but with their gilded frames subtly unrestored.

Not that Pears, draped gracefully over a sofa, has not experienced the rougher side of life. The dreamy landscape of Provence, lovingly evoked, is the background to his new novel The Dream of Scipio (Jonathan Cape, £17.99). But Pears says that: "When I first went to Italy, I worked in a radiator factory in Turin, which was one of the centres of the Red Brigade. The personnel manager had a loaded gun on his desk."

Pears also worked as a Reuters correspondent in Italy, including sports reporting – even handball, "about which I knew nothing. Handball results came out on a Saturday night. There was a subscriber in France who always wanted 200 words on the most important match – I would be describing entirely the wrong game." He also encountered the Art Theft Police who feature in his detective series involving Jonathan Argyll, sleuthing art historian.

Pears expanded his image as a writer a few years ago by writing An Instance of the Fingerpost. A fat, learned work set in 17th-century Oxford, it was an unlikely runaway success and took him across the gulf that still, in British convention, separates crime-writing from literary fiction. At its heart was the question of whether a young girl had been unjustly accused of murder. The novel displayed arcane scholarship and the multi-viewpoint technique used by Lawrence Durrell in The Alexandria Quartet.

The Dream of Scipio breaks fresh ground again. The title refers to a Neoplatonic treatise (invented by Pears), the work of a fifth-century bishop, which will be rediscovered by two later scholars. The book is essentially a philosophical novel, a bold venture in the current literary world. "Lots of things I had never done before," says Pears. "Writing a book without a murder solved in it, which gives you a plot and a sense of structure. And splitting the book into three so that you have the stories running together was very difficult."

Three lives, three crises, located variously during the decline of Roman civilisation, the Black Death of the Middle Ages and the Nazi occupation of France, intermesh. All have as a preoccupation the theme of a man who falls in love, intellectually or emotionally, with an outsider. Here the link between life and work is obvious: Pears's wife, in a marriage of obvious mutual devotion, describes herself as a "Jewish agnostic", and two leading characters fall in love with Jewish women. "Falling in love with someone outside your own culture – yes, it's doing something that takes you outside yourself and makes you look at yourself."

In the earliest of the stories, Manlius Hippomenes is a Gallic aristocrat, a revered Christian cleric nevertheless anxious to preserve the learning of the classical world in the face of barbarians at the gates. Manlius becomes enamoured of ancient philosophy in the person of Sophia: careless of her appearance, fiercely intellectual, yet possessed of intense, erotic fascination. (It's here, if anywhere, that we have a touch of Iris Murdoch). Sophia introduces a proposition which becomes a recurring theme of the book: Solon of Athens said that if a society descends into war, anyone who refuses to take sides should be exiled when order is restored, an issue which will suddenly become relevant to modern times.

Manlius does not take the right side. To gain popular support, he betrays the Jewish community, earning Sophia's wrath, and his misuse of his intellectual gifts to argue on the side of evil reverberates down the long centuries of European intolerance.

The second story is that of Oliver, a medieval poet who recovers a manuscript of Manlius's treatise as the Black Death advances. Oliver is faced with the problem of which side to take, settled when he falls in love with a woman from the Jewish community. When Jews are accused of causing the sickness by poisoning wells, Oliver manages to save her, at a terrible cost. His moral choice will echo down the centuries too, for it results in one of the few decrees of tolerance to enlighten a shameful record of persecution, influencing Pope Clement to declare Jews innocent of all charges in the matter of plague.

There has been a crop of novels dealing with Occupied France, but in the third narrative Pears explores a new aspect. "The standard way of treating France in the Forties is basically to have heroic resistance and snivelling collaborators, and it clearly wasn't like that ... People didn't make up their minds on the basis that the Allies were going to win and the Germans were going to kill off the Jews, because neither of those was known. People had to proceed on the basis that the Germans had won, and that there was no other choice, and no one was going to come to their rescue."

The dilemmas once faced by Manlius and Oliver are visited upon a cultured Frenchman in Vichy France who is studying Oliver's poems and Manlius's treatise. Pears creates three modern characters, Julien, Bernard and Marcel, childhood friends who in adult life find themselves faced with the same dilemma: how do you react when the barbarians are at the gate?

Bernard joins the Resistance (he is based on Jean Moulin, the Resistance leader murdered by Klaus Barbie). Marcel collaborates. "Marcel is put in a position where he narrows his choices down," says Pears. "You do what seems logical and reasonable and for the best through higher motives, and it leads you further and further down to the place where you realise you're turning into a monster." Julien finds himself in a position of unexpected power, but how far will he co-operate with the Nazis? "I got the idea for Julien's character from Jerome Carcopino, the famous classical scholar. He was the Minister of Education in Vichy France who was responsible for introducing all the anti-Semitic legislation, which threw a lot of his Jewish friends out of jobs. This man was the ultimate in the classical tradition, the supreme example of civilisation, clearly a very charming, pleasant, kind man ... how was it that this nice man came to do what he did?"

Julien fought at Verdun and is at first convinced he must support order during the occupation because of that terrifying experience. Yet, fearful for the fate of his Jewish lover, he finally sees the truth: "It is the civilised who are truly barbaric and the Germans are merely the supreme expression of it." His choice is a gesture of defiance, in a powerfully moving finale to a complex narrative of evil and heroism.

Pears walks out with me into the orderly streets of a university city, a bastion of European culture. Does he share Manlius's feelings that the barbarians are at the gates? "No – and I don't think they were then. It's more about how the idea of them can bring out the barbarian in civilised people. Civilisations tend to be very strong and to be killed by themselves. Rome would never have fallen if it hadn't crumbled first."

Iain Pears: biography

Iain Pears was born in 1955. He was educated at Wadham College, Oxford, has worked as a journalist and television consultant, and has lived in France and Italy. A student of Francis Haskell, he wrote a doctoral thesis on interest in the arts in 18th-century England. Pears is also the author of seven detective stories set in Italy featuring Jonathan Argyll, an art historian, and the Rome Art Theft Squad. He edited The Adventures of Sherlock Holmes and The Mysteries of Sherlock Holmes for Penguin Classics. In 1997 he published An Instance of the Fingerpost, a multi-viewpoint historical novel set in Oxford in the 1660s. His latest book is The Dream of Scipio (Cape, £17.99), with a Provençal background, which interweaves three linked episodes. Iain Pears lives in Oxford with his wife, Ruth Harris.