THE BOOKIES ARE CONFUSED, and who can blame them? They don’t know what to do about Ian McEwan’s new book (let’s just call it that, for now) On Chesil Beach, when it comes to betting on this year’s Man Booker Prize. You’d think it would be a shoe-in, as far as entry is concerned: “McEwan’s latest fiction is full of richness,” said Jane Shilling in these pages last week, “of serious thought about the nature of human relationships, informed by a poetic sensibility and expressed in prose whose lyricism never errs on the side of self-indulgence.” No argument there, surely? Hang on.

Its length shy of 200 pages, is this a novel or — whisper the word — that mysterious creature, a novella? It’s an awful word, isn’t it, novella — like maisonette, neither one thing nor the other. Graham Sharpe, literary pundit for William Hill, is holding off taking bets: “There is some doubt about whether it is a novel or a novella. The latter is apparently banned by the Booker, although there seems to be no definition as to what makes a novella a novel or vice versa.” Indeed, the latter is “banned”: the rules state that “any full-length novel, written by a citizen of the Commonwealth, the Republic of Ireland or Zimbabwe, is eligible. Such a book must be a unified and substantial work. Neither a book of short stories nor a novella is eligible.”

The trouble is that while it is (relatively) simple to define a book of short stories (and whether books of stories should be eligible is a question to save for later) no one seems to know what a novella is. When I asked John Sutherland, Emeritus Lord Northcliffe Professor of Modern English Literature at University College London and former Man Booker chair, he answered, in effect, how long is a piece of string? McEwan’s Amsterdam, it is worth noting, actually won the Booker; it is not a very long book. Yet it was judged clearly to be a unified and substantial work of fiction; and surely On Chesil Beach can be described that way too.

What about Heart of Darkness? What about A Christmas Carol? Those, surely, are U&SWoF (say it: youandesswoff) despite their length. And yet we know that because we know it, not because we can count up the number of words in each book and come up with a mathematical answer.

Of course, perhaps all Mr Sharpe has to do is head for www.ianmcewan.com: where On Chesil Beach is simply described as a novel . . .

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