Let's talk about literary sex: Fifty Shades is the latest chapter in literature's love affair with erotica but are readers more prudish than ever?

Explicit: The super-hit novel Fifty Shades of Grey has been criticised not for its graphic sexual content but for lacking literary merit and glamorising abusive relationships (Getty Images)

In 1965, WH Auden anonymously published a one-poem pamphlet that contained his brilliant "The Platonic Blow", a graphic description of a sexual encounter between two men. Until 1967, male gay sex was illegal in the UK. That's right: in those days, we were bonkers enough to persecute harmless bonkers. If Auden were alive now and had written the same poem, say, last week, I like to think he would have felt able to publish it under his own name, because since the 1960s we have become so much more enlightened and sane about sex and sexuality. Haven't we?

In some respects, the answer has to be "yes". Equal marriage is a huge step forward; there will soon be many puzzled murmurings of "Really?" when we contemplate, retrospectively, the horror of marriage having been forbidden to same-sex couples for so long. We have made progress in the direction of acceptance of sexuality in other ways as well: it is now allowable – even quite cool, as far as I can tell – to admit to masturbation, once viewed by many as a shameful practice. There's a superb Mitchell and Webb sketch based around the idea that the main drawback of working freelance from home is that incessant wanking will distract you from your work.

Graphic sexual writing in poetry and prose is no longer frowned upon in the way that it was in 1960, when the explicit version of Lady Chatterley's Lover was published and became the subject of an obscenity trial. By contrast, in the summer of 2012, almost every woman on a sun lounger beside a swimming pool had a copy of the far more explicit super-hit novel Fifty Shades of Grey in her hand and seemed not in the least ashamed to be holding it. Interestingly, Fifty Shades has been criticised since its publication, but not for its graphic sexual content. Instead, the novel has been accused of lacking literary merit, portraying consensual BDSM in an unjustly negative light, and glamorising abusive relationships.

The third charge is interesting, and links to one of the ways in which I believe we have become less enlightened as a society. I don't think Fifty Shades of Grey glamorises abuse. What is true, though, is that Christian Grey, a man who behaves unacceptably towards Ana, the novel's protagonist, is not portrayed as a grotty creep to be avoided, but as a sexy screw-up with some redeeming features and many unfortunate compulsions that make Ana miserable and uncomfortable, and which make their love seem almost certainly doomed. The relationship is shown as a complex one: Ana is drawn to Christian, and simultaneously appalled by him.

WH Auden anonymously published a one-poem pamphlet that contained his brilliant 'The Platonic Blow', a graphic description of a sexual encounter between two men (Getty Images)

What I have described is the plot, which should not be confused with what the novel is "saying". Is it necessarily saying any more than: "Here is a story about two people that you might find interesting"? To those who would answer "Yes", I would ask the following question: is the movie Psycho saying that motel owners are all unhinged killers? There is a danger in attributing moral messages to books and films that might simply seek to tell stories. Some of these might be about people behaving atrociously, or suffering the negative effects of others.

Perhaps, as contemporary readers, we imagine works of art to be saying something about important controversial issues because we want and need them to be doing so. If we convince ourselves that they are, then we can pick fights with them. We can condemn and insult them; we can lash out. As a Twitter addict, I am constantly reduced to shudders and excessive swearing by the levels of moral condemnation that I see online. Every day, some new sinner is branded an unmitigated scumbag by hundreds if not thousands of tweeters.

Leafing through The Poetry of Sex with this new contemporary public appetite for moral condemnation in mind, I wonder which of the poems would elicit snarls of disapproval. There is no poem in the anthology suggesting that it is out of order to tell sex-workers and female porn film actors that they are victims when they do not believe they are; there is not a single villanelle ripping into censorious porn filters. Ah, well, what can you do? An editor cannot manufacture submissions simply to cause controversy.

Online reaction: Many people have been outraged by President Hollande's indiscretions (Rex Features)

Perhaps the substantial sub-section of The Poetry of Sex that covers sexual infidelity will do the trick. The recent online reaction to President Hollande's indiscretions has been interesting. Many people seem as outraged as only his deceived partner has the right to be. The consensus seems to be that because Hollande has lied in his personal life, he cannot and should not be trusted with anything (let alone France) or be forgiven, ever.

Recently the Mail Online ran a column headed, "People, Stop Having Affairs!" There was no twist; the article really did suggest that no married person should ever have illicit sex. I immediately thought of Gilbert and Sullivan's 1885 comic operetta, The Mikado:

"So he declared in words succinct/That all who flirted, leered or winked/Unless connubially linked/Should forthwith be beheaded".

Funnily enough, the objections raised on Twitter were primarily literary ones: how dull it would be for fiction and all art forms if there were no adultery. No Anna Karenina, no Madame Bovary, no Fatal Attraction, no "Adultery" by Carol Ann Duffy, no innumerable brilliant sonnets by Edna St Vincent Millay, or memorable and moving verses by Wendy Cope. The "What about art?" criticism was the literary wing of Twitter's way of saying, "Steady on – we're heading for dangerous moral absolutism here, and people are complex creatures."

The best art surely needs to understand and accept that people are weak, flawed, vain, scared, angry, and bemused much of the time. This has always been, and will always be, reflected in our sexual behaviour, and in how we write about it. And now I must go and complete my rondeau redoublé provisionally entitled The Two-Hugh (Grant and Laurie, of course) which was sadly too late to be included in the book.

The Poetry of Sex', edited by Sophie Hannah, is published by Viking