I’M TOYING with an idea for a novel. It revolves around a middle-aged journalist who sees his life slipping past him. Desperate for fame, adulation and the chance of becoming a TV star, he makes a pact with the Devil, a latter-day Mephistopheles who bears an uncanny resemblance to the agent Max Clifford. In return for the promise of his immortal soul, the journalist — let’s call him Faust — gets the chance to appear on Celebrity Big Brother and is very soon an item with Jordan or Chantelle, or possibly both. I’m still working on the details.

Because this will obviously be a post-modern novel, I intend to play around with the ending, which may, against the odds, turn out all right for Faust. After all, what is a soul worth these days? And Clifford was only on a percentage anyway.

There is, however, a fly in the ointment. The whole project has had to go on hold as we await the outcome of events in the High Court, where the future of literary plagiarism is being determined. Dan Brown, who wrote the bestselling novel The Da Vinci Code, is being accused of stealing his plot from the authors of an earlier book, The Holy Blood and the Holy Grail — a cumbersome title, but one whose central thesis is alleged to be strikingly similar to Brown’s.

I’m worried. If borrowing plots is to be forbidden, where does that leave me, and, indeed, the rest of the literary world? I may as well confess now that I picked up the idea for my novel from some obscure German called Goethe who seems in turn to have lifted it from Christopher Marlowe, and he got it from a bit of medieval folklore, so quite where that leaves anyone with an eye for a good story, I don’t know. After all, as Christopher Booker revealed in his book The Seven Basic Plots, there is a strict limit to what you can come up with, whether it is “overcoming the monster” (which covers everything from Beowulf to Harry Potter), “rags to riches” (Great Expectations) or “the quest” (which takes in Chaucer and Tolkien, to say nothing of the Holy Grail).

A distinction needs to be made here. Plagiarism in its most common form — cutting and pasting whole sections of other people’s academic work from the internet — is no better than theft; it deserves to be punished; but it is easily counteracted. You can buy a piece of software which is a form of electronic detective that casts its eye over the finished product and lets you know in seconds how much is simply copied, passage for passage. There is no such simple test for a work of fiction. An idea may be “inspired” by a previous work, as Alex Haley claimed when he was accused of lifting his book Roots from an earlier work on African slavery; or it may be an “echo” from another writer, as Graham Swift argued, after claims that he had imitated William Faulkner’s As I Lay Dying rather too closely. T. S. Eliot thought that plagiarism in the hands of a good writer was an artform: “Immature poets imitate; great poets steal,” he said simply.

Shakespeare purloined his best plots from Holinshed. West Side Story was stolen from Shakespeare. Paradise Lost is shamelessly based on Genesis. Martin Luther King plagiarised part of the doctoral thesis which became, later, his finest speech. Zadie Smith makes no bones about basing her latest novel On Beauty on E. M. Forster’s Howards End: “He gave me a classy old frame, which I covered with new material as best I could,” she says.

All of these, however, can plead literary merit. The same defence is not available to the two blockbusters currently slugging it out in the High Court. They stand on the shaky ground of fictional history and pseudo-research.

Both their books are essentially baloney — made-up versions of the past, mixing occasional facts with bare-faced invention, apparently passing themselves off as some form of hidden truth. Their success owes less to the strength of their narrative or the richness of their prose than to the widespread belief, which they have done little to undermine, that they have disinterred a secret history, covered up by the Church for hundreds of years.

This makes the case, therefore, as much a test of history as it is of plagiarism. You cannot plagiarise a genuine historical fact, only a made-up one. If I can demonstrate that my Faust is based on hard and proven research,that the man existed and that his case is meticulously documented in the 16th-century archives of Wittenberg, then I can genuinely claim that I am recycling history rather than stealing a good story. I will be able, with the greatest confidence, to fight off the heirs and successors of J. W. Goethe, should they care to challenge me.

This then must be the dilemma for those who seek to defend their own versions of made-up history: they can only sue and win if they can demonstrate that their ideas are fictional, invented and therefore entirely their own property. If, on the other hand, they succeed in proving that their research is genuine, and their investigations firmly based, then they have made a signal contribution to history — a history that belongs to us all. Their revelations become as public as the secrets of the Enigma Code, the Suez pact, or the British presidency of the European Union.

This case may help to define the difference between genuine history on the one hand, and fiction on the other. If so, it will have done a great service to both. We may need a Mephistopheles, however, to detect the difference.

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