Tom Sutcliffe: Opening lines that can be a giveaway

Can you judge a book by its epigraph? That you do is surely true, since at the point when you turn that particular page of a new novel it's pretty much all you've got to go on. Yes – the book's cover will have started work on you already, but you know that to be the creation of the marketing department. It's inadmissible as evidence of literary intent. But now, here, you are for the first time in the presence of the author and you are entitled to weigh up what you've been given. That you are expected to judge a book by its epigraph is also true, since it would hardly be there otherwise. You know perfectly well that it has designs on your judgement. It would be impolite to brush past without a nod in its direction, even if you suspect that it stands at the door like a spin-doctor, trying to tilt the verdict in the right direction.

And it's startling how often the epigraph can start you off on the wrong foot, precisely because you sense it lingering there with transparent intent. Having read an awful lot of them over the last few months, as the Booker b.p.w needle (books per week) needle flickered into the red, I'd like to suggest a few dos and don'ts to writers who'd prefer their readers not to begin in a state of active irritation.

The first rule would be stick to one epigraph only. Two looks like indecision, three like intellectual greediness and four like a kind of despair – with the author opting for a shotgun spread in the desperate hope of hitting the target with at least one literary pellet. There are exceptions to this rule. Martin Amis just about gets away with three for The Pregnant Widow, but only because his first one (an explanatory quote from Alexander Herzen that explains the title) is so good and at least one of the others is a dictionary definition of a single word. Even there, though he'd have been better to go with his first choice – and avoid the jitter of indecision. Neil Mukherjee, though, who opts for three in his novel A Life Apart, clearly overdoes it. There may be a fantasy literary world in which Cynthia Ozick, John Milton and Rabindranath Tagore meet for coffee, but their rendezvous here just looks showily erudite. Even worse is the strategy adopted by the writer Richard Aronowitz in his book It's Just the Beating of My Heart, who pairs Walter Benjamin with Lloyd Cole and the Commotions in a transparent high-brow/low-brow combo.

The second rule is less clear cut and concerns the delicate judgement of literary proximity. The rough rule of thumb might be this. Never quote from a writer who will provoke invidious comparisons. Ian McEwan made this mistake at the beginning of Solar, taking an epigraph from John Updike ("It gives him great pleasure, makes Rabbit feel rich, to contemplate the world's wasting, to know the earth is mortal too") and unhelpfully raising the possibility that the book's ambition had already been achieved more pithily. Of course, it can be just as hazardous over-compensating in the other direction – like the chick-lit potboiler who opens with a quote from Racine or The Pillow Book of Sei Shonagan. You don't want to look like the only person who doesn't realise you're playing way out of your league. Wit helps, though unhelpfully wit is sometimes only apparent after you've read the novel. Alan Warner's use of Kafka at the beginning of his novel The Stars in the Bright Sky looks like a classic case of gravity-stealing, but turns out to be slyly appropriate to his comedy.

The final rule would concern simplicity. Arcane and enigmatic epigraphs are all very well – but they leave you open to a charge of pretension and, since they create a knot which can only be untied by the book itself, there's a sense in which the tail is wagging the dog. Better dispense with them entirely I would have thought. My favourite epigraphs of the past year have both been marked by a daring – or even belligerent – straightforwardness. One was Lionel Shriver's epigraph for So Much for That – Ben Franklin's remark that "Time is Money", a cliché so familiar that she might as well have written "I can't be bothered to think of a smart epigraph". And yet both the quote and it's take-it-or-leave it attitude are perfect for the book. The other one was the dedication/epigraph for Howard Jacobson's novel The Finkler Question, which memorialises three recently dead friends and adds a Shakespeare-inflected question: "Who will now set the table on a roar." Both eschew cleverness in favour of mood – and they set the mood perfectly.

The Coen brothers depict the correct formula

I didn't get a flood of responses to my request for suggestions of lecture scenes in movies that aren't intellectually risible, though I did get at least one suggestion that made me laugh out loud at my desk, which I'll pass on later.

David Gleadhill reminded me of the excellent blackboard scene in Alan Clarke's Made in Britain, in which Geoffrey Hutchings sketches out Tim Roth's bleak life prospects, but, good as that is, it doesn't quite fit the bill, I think. I was after scenes that involve students and an academic setting. Tom Foley's suggestion of John Houseman's scene in the film Paper Chase, in which he tells his assembled students "You teach yourselves the law. I train your minds. You come in here with a skull full of mush and if you survive, you'll leave thinking like a lawyer" meets that requirement, but surely counts as a representative of a slightly different cinematic trope – the eye-opening induction, a grouping which would include the first address from the Drill Sergeant in Full Metal Jacket (and, come to think of it, the Made in Britain scene as well).

However, Andrew Murray's suggestion absolutely hits the nail on the head. It's the sequence from the Coen brothers film A Serious Man in which Larry Gopnik introduces his students to Heisenberg's Uncertainty Principle, a scene which begins with a close shot of Gopnik's hand, scribbling out mathematical formula as he recites them, and concludes with a longshot showing a vast blackboard entirely filled with algebraic symbols.

Gopnik's summary? "It proves we can't ever really know what's going on." That passes surely. Intellectually unimpeachable (I do hope his formulae are correct), and a great sight gag, too. Do yourself a favour and watch it on YouTube.

A victim of his own finesse

Watching Neil Simon's The Prisoner of Second Avenue the other day I found myself thinking that he was a classic example of a self-redundifying writer (a concept that Sarah Palin hasn't explored yet but surely will, given enough time). The play looks a little creaky these days, but one of the reasons for that is that the querulous New York comedy it delivers has been so ruthlessly exploited by American sitcoms like Seinfeld and – in a form with more hugging and learning – Friends. And I think it's arguable that neither Seinfeld nor Friends would have looked quite as they did without Simon's example of bickering Manhattan relationships. Other stuff goes into the DNA of the later programmes, of course, but Simon is a good example of the kind of talent that paves a way for its successors and then suffers because it has enough staying power to look slightly old-fashioned alongside them.