Does it help writers to drink? Certainly Jack Kerouac, Dylan Thomas, John Cheever, Ernest Hemingway and F Scott Fitzgerald thought so. But, wonders Blake Morrison, are the words on the page there despite and not because of alcohol?

Recent research suggests that Dylan Thomas might not, after all, have drunk himself to death. What his doctor in New York took to be delirium tremens and treated with morphine may have been bronchitis and pneumonia, which morphine injections only made worse – after the third of them, he went into a coma. Still, there's no doubt that Thomas had been drinking heavily in the days leading up to his admission to hospital – indeed for large periods of his life. The previous day he'd opened a bottle of Old Grand-Dad whiskey and offered a glass to the maid cleaning his hotel room. Then, after more drinks with his lover Elizabeth Reitell, he left his bed at 2am and went to a bar, telling her on his return that he had drunk 18 straight whiskies.

Thomas was prone to exaggeration. He once bragged that he had drunk 40 pints of beer, and a character in his Adventures in the Skin Trade claims to have drunk 49 pints of Guinness straight off. According to the bartender who served him that fateful night, Thomas drank only six or at most eight whiskies, not 18. But American measures are twice the size of British ones. And his health had suffered over the years from alcohol and cigarettes: as well as having gout, emphysema and a fatty liver, he was physically exhausted through insomnia. The diagnosis on his admission to St Vincent's, alcoholic encephalopathy, might have been wrong, and with different treatment he might have recovered. But it wasn't as if he hadn't been warned.

Thomas's death is the stuff of legend, and it's no surprise to hear that a TV film, with a script by Andrew Davies, is being made about it, to coincide with the centenary of the poet's birth next year. Part of the legend, no matter how false, is that American hospitality is what killed him – the innocent from Britain goes on a lecture tour, is tempted to taste the Big Apple, then falls. Behind the Thomas story, though, is an older myth, that poetry and alcohol go together, as complementary means to achieve transcendence: "The excitement of alcohol and the excitement of fantasy are very similar," John Cheever said. You can trace the idea back to ancient Greece, where poems would be recited at drinking parties or symposia (often competitively, in a "capping game", one person following another). The idea is common to other cultures, too, including the Chinese, where in the third century AD the seven sages of the Bamboo Grove retired to the country to drink wine and compose verse: "Once drunk, a cup of wine can bring 100 stanzas," the poet Xiuxi Yin claimed. The drunker the bard, the more the words flowed.

Dylan Thomas in New York City, c1950. Photograph: Hulton Archive/Getty Images

Thomas epitomised this tradition of the roistering rhymer – to the distaste of Kingsley Amis, who wrote a singularly unpleasant epitaph for him:

They call you "drunk with words";

but when we drink

And fetch it up, we sluice it down

the sink.

You should have stuck to spewing

beer, not ink.

Does it help writers to drink? Do they drink any more heavily than any other social group – doctors, lawyers, shop assistants or (see Mad Men) advertising executives? A famous drinker himself, Amis considers this question in his Memoirs, and – comparing writers to actors – suggests "displaced stage fright as a cause of literary alcoholism. A writer's audience is and remains invisible to him, but if he is any good he is acutely and continuously aware of it, and never more so while it waits for him to come on, to begin p.1. Alcohol not only makes you less self-critical, it reduces fear." According to Amis, a large glass can supply "that final burst of energy at the end of the day" but should be avoided any earlier: "The writer who writes his books on, rather than between, whisky is a lousy writer. He is probably American anyway."

Amis had little time for American writers, which explains the prejudice behind that last remark. But it's true that modern American literature is strewn with examples of alcoholic excess: Poe, Hemingway, Faulkner ("I usually write at night. I always keep my whiskey within reach"), Hart Crane, Tennessee Williams, Truman Capote, Dorothy Parker ("I'd rather have a bottle in front of me than a frontal lobotomy"), Ring Lardner, Raymond Chandler, O Henry, Jack London, Delmore Schwartz, F Scott Fitzgerald, ("Too much champagne is just right"), John Berryman, Jack Kerouac, Charles Bukowski, Anne Sexton, Patricia Highsmith – the list is long even without including those, such as Hunter S Thompson, more renowned for their experiments with other substances ("I hate to advocate drugs, alcohol, violence or insanity to anyone, but they've always worked for me"). In a new book, The Trip to Echo Spring, Olivia Laing looks at six American writer-alcoholics, beginning with the story of how the ageing, critically acclaimed John Cheever and an aspiring young unknown called Raymond Carver became drinking buddies while teaching in Iowa in 1973. "He and I did nothing but drink," Carver later wrote. "I mean, we met our classes in a manner of speaking, but the entire time we were there … I don't think either of us ever took the covers off our typewriters."

Laing's is a travel book as well as a series of critical biographies. Her quest takes her to some of the places where her chosen six (Hemingway, Williams, Carver, Cheever, Berryman and Fitzgerald) lived, wrote and drank. It's a journey spanning thousands of miles – New York, Chicago, Port Angeles, New Orleans, Atlanta, Key West – but it's the distance from the writing desk to the nearest bottle that preoccupies her. It's also a personal journey, as Laing grew up with alcoholism in her family and wants to make sense of the disease. To her, no romance attaches to it at all.

She takes her title from a line in Cat on a Hot Tin Roof, where one of the characters says "I'm takin' a little short trip to Echo Spring" – his nickname for the drinks cabinet and the brand of bourbon it contains. It's a resonant phrase, as Laing says, because most of her writers had a deep love for water (as she does too: her previous book, To the River, was about water, English literature and Virginia Woolf). It also suggests both the myth of Narcissus (writers are nothing if not narcissistic) and the time-honoured link between springs (and wells) and poetic inspiration. In classical legend, Hippocrene, the fountain on Mount Helicon created by Pegasus's hoof, is sacred to the Muses and inspires whoever drinks from it. Keats refers to it in his "Ode to a Nightingale", while craving something stronger:

O, for a draught of vintage …

O for a beaker full of the warm

South,

Full of the true, the blushful

Hippocrene,

With beaded bubbles winking at the

brim,

And purple-stained mouth.

That I might drink and leave the

world unseen …

The lines prompted Bentley's clerihew: "John Keats/Among other notable feats/Drank off a soup-tureen/Full of the true, the blushful Hippocrene." They're also among those analysed by Christopher Ricks in his book Keats and Embarrassment. "Blushful" doesn't just evoke the colour of the wine (a red or rosé), but implies its power to make our skin flush or, if drunk to excess, to make us do things we blush to remember afterwards.

Embarrassment is a common consequence of drink. John Updike felt it on Cheever's behalf when he came to take him to a concert one day and met him standing naked outside his flat: "His costume indicated some resistance to attending the symphony but I couldn't imagine what else, and I primly concentrated on wedging him into his clothes." Equally blushful is Kingsley Amis's story of his friend Philip Larkin sitting through a school literary evening after a heavy beer-drinking session, finding himself caught short, and trusting that the absorbent qualities of his heavy overcoat would not betray him when he pissed himself – "It turned out that he had miscalculated." The fallout from constant heavy drinking is worse than mere social embarrassment: illness, insomnia, squalor, violence, misery for oneself and others. But a bohemian chic is still associated with boozy writers, especially dead American male novelists. There are websites that give you the recipes for their trademark drinks: Faulkner's mint julep, Hemingway's mojito, Chandler's gimlet, Kerouac's margarita, Fitzgerald's gin rickey.

Literature abounds with paeans to the hard stuff. Sometimes it's a matter of national pride, with ale, stout, vodka, absinthe, chianti or, in Burns's case, the peaty goodness of Scotch whisky being celebrated for their miraculous powers ("O whisky, soul o' plays an' pranks,/Accept a bardie's gratefu' thanks"). More often, as with Byron, the spirit is one of carpe diem – drink now because who knows what tomorrow will bring:

… for the future – (but I write this

reeling,

Having got drunk exceedingly today,

So that I seem to stand upon the

ceiling)

I say – the future is a serious matter –

And so – for God's sake – hock and

soda water!

The positive spin put on alcohol in the Bible (with the marriage feast at Cana – "the only worthwhile miracle in the New Testament", as Christopher Hitchens called it) and in classical legend (with Dionysus the god of ecstasy and wine) is something that John Cheever puzzled over. Why is drunkenness not among the deadly sins, he wondered? Why in early religious myths and legends is alcohol presented as one of the gifts of the gods? "The belief that to be drunk is to be blessed is very deep. To die of drink is sometimes thought a graceful and natural death – overlooking wet-brains, convulsions, delirium tremens, hallucinations, hideous automobile accidents and botched suicides … To drink oneself to death was not in any way alarming, I thought, until I found that I was drinking myself to death."

Cheever was in AA when he wrote this, earnestly facing the truth of his addiction. But he's wrong to say that literature and religion are wholly indulgent of indulgence. Dionysus is also Bacchus, a dissolute lord of misrule. And there are many condemnations of heavy drinking in the Bible: "Woe to those who rise early in the morning to run after their drinks, who stay up late at night till they are inflamed with wine." (Isaiah 5:11). Then there's Homer: "[I]t is the wine that leads me on, the wild wine that sets the wisest man to sing at the top of his lungs, laugh like a fool … it even tempts him to blurt out stories better never told." Cheever surely knew his Shakespeare, too.

John Cheever at home in Ossining, New York. Photograph: Paul Hosefros/Getty Images

MACDUFF: What three things does

drink especially provoke?

PORTER: Marry, sir, nose-painting,

sleep, and urine. Lechery, sir, it

provokes, and unprovokes; it

provokes the desire, but it takes away

the performance. Therefore, much

drink may be said to be an

equivocator with lechery: it makes

him, and it mars him; it sets him on,

and it takes him off; it persuades him,

and disheartens him; makes him

stand to, and not stand to; in

conclusion, equivocates him in a

sleep, and, giving him the lie, leaves

him.

In Cheever's lifetime, there was also Malcolm Lowry's Under the Volcano (1947), about a man who destroys himself with mescal – a novel that's brilliantly insightful about the lure of alcohol written by an author who would succumb to it 10 years later. There was plenty here to have persuaded Cheever that his drinking had no historical, religious or literary endorsement. But alcoholics are never short of justifications for their addiction. Someone or something else is always to blame:

"Wine was almost a necessity for me to be able to stand her [Zelda's] long monologues about ballet …" (Fitzgerald)

"Modern life … is often a mechanical oppression and liquor is the only mechanical relief." (Hemingway)

"The writer cultivates, extends, raises and inflames his imagination. As he inflates his imagination, he inflates his capacity for anxiety, and inevitably becomes the victim of crushing phobias that can only be allayed by crushing doses of heroin or alcohol." (Cheever)

"I began to drink heavily after I'd realised that the things I'd most wanted in life for myself and my writing, and my wife and children, were simply not going to happen." (Carver)

"Why drink so, two days running? / two months, O seasons, years, two decades running? / I answer (smiles, my question on the cuff). / Man, I been thirsty." (Berryman)

Genes may lie behind a predisposition to alcohol. Childhood trauma, too: suicidal dads (Berryman and Hemingway had fathers who killed themselves with shotguns) and unmaternal mums (Cheever called Gilbey's gin "mother's milk"). But of Laing's six writers, only Tennessee Williams speaks with candour and conviction: "Why does a man drink? There's two reasons, separate or together. 1 He's scared shitless of something. 2. He can't face the truth."

As alcoholics are habitually in denial about their habits, you would think they'd be ill-equipped for the ruthless truth-telling required in autobiography. But recovery memoirs have always been a thriving genre. Of recent contributions, John Sutherland's Last Drink to LA and Rosie Boycott's A Nice Girl Like Me stand out; with most, the titles tell you all you need to know – Diary of an Alcoholic Housewife, Dead Drunk, Mother's Ruin, I'll Stop Tomorrow, Drinking: A Love Story. The narrative arc is redemptive: look-how-low-I-sank-before-I-was-saved. The author comes out of a fug to recognise the error of their way: "Their glasses were taken from them, & they saw," as Berryman puts it ("Dream Song 46"). The only mystery is why no major writer has chipped in with a memoir to rank with De Quincey's Confessions of an English Opium-Eater or William Styron's chronicle of depression, Darkness Visible.

Fiction is a better route, perhaps: the unspeakable truths can go into the mouths of made-up people. But as Kingsley Amis complained, readers tend to equate authors with their protagonists, and with good reason. In John Berryman's unfinished novel Recovery, the protagonist is called Alan Severance: despite the name, his experience of rehab isn't easily divisible from the author's. As for Fitzgerald, when he was sacked by MGM towards the end of his life, he took to writing stories for Esquire about a small-time alcoholic scriptwriter, as if to ward off the thought that this was what he had become. No one was fooled. "I cannot consider a pint of wine at the day's end as anything but one of the rights of man," he'd once said, but by now it was a pint of gin a day, and his escapades (losing his car licence, getting into fights, being thrown out of clubs, etc) were common knowledge. He reached his nadir when he got drunk with two tramps and brought them home, inviting them to help themselves to his ties, shirts and Brooks Brothers suits.

Fiction may look like the right form for alcoholics, as their dependency teaches them to be good at lying. But holding a novel in your head becomes more difficult when you're holding a glass in your hand as well. "A short story can be written on a bottle," Fitzgerald told his editor Max Perkins, "but for a novel you need the mental speed that enables you to keep the whole pattern in your head and ruthlessly sacrifice the sideshows." Many poets have written a line or two when pissed, but few of those lines stand up next day. Even poetry readings can be ruined by woozy timing and slurred pronunciation. I learned my lesson early on at a reading at the University of East Anglia with Craig Raine; we'd been treated to a generous lunch on campus by the-then writer-in-residence Paul Bailey, and in an austere seminar room at 5pm the effects were a little too discernible.

Drink is better used as the backdrop to a poem, rather than in the creation or recital of it. In "September 1st 1939" Auden's thoughts about impending war would have less force if expressed in isolation or abstractly. Instead, they're set in a particular place, "one of the dives/On Fifty-Second Street", among commuters who share his anxiety and whose boozing is a desperate effort to show an affirming flame: "Faces along the bar / Cling to their average day: / The lights must never go out, / The music must always play."

Seamus Heaney's poem "Casualty" – an elegy for a fishing acquaintance blown up in a bomb attack on a pub after defying a curfew – is similarly enriched by the portrayal of the man's taciturn independence both in a boat and at the bar: "He would drink by himself/And raise a weathered thumb/Towards the high shelf,/Calling another rum/And blackcurrant, without/Having to raise his voice,/Or order a quick stout/By a lifting of the eyes/And a discreet dumb-show/Of pulling off the top."

Drink also comes in handy as a device for novelists and playwrights. It's not just a prop (like the whisky decanter that's the staple of British middle-class drama from Rattigan to Pinter), but a way to advance plot – "for accelerating the story, making someone throw a pass or insult somebody else sooner, more outrageously, etc, than they might when sober", as Kingsley Amis said. He might have been thinking of the scene in Lucky Jim where the hero, Jim Dixon, makes his escape from a boring madrigals evening, gets drunk at the pub, and then burns a hole in the bedsheets at his boss's house. Less comically, there's Othello, in which Iago usurps Cassio by getting him drunk and into a brawl and thereby dismissed from Othello's affections: "O god, that men should put an enemy in their mouths to steal away their brains!"

In Russian literature, the drink that steals away men's brains is vodka. Tolstoy, repenting his youthful follies ("lying, thieving, promiscuity of all kinds, drunkenness, violence, murder"), founded a temperance society called the Union Against Drunkenness, and designed a label – a skull and crossbones, accompanied by the word "Poison" – to go on all vodka bottles. In the event, the health warning wasn't adopted but Tolstoy's views on vodka seep into his fiction, as do Dostoevsky's in The Devils ("The Russian God has already given up when it comes to cheap booze. The common people are drunk, the children are drunk, the churches are empty"). Chekhov was more ambivalent. As Geoffrey Elborn shows in his new cultural history, The Dedalus Book of Vodka, he was torn between his knowledge as a doctor and his understanding of human nature. Two of his brothers were alcoholic, and he denounced vodka companies as "Satan's blood peddlers". But he sympathised with the Russian peasantry, for whom vodka was nectar. And in his stories and plays, those who drink excessively – like the army doctor Chebutykin in The Three Sisters – are portrayed with humour and compassion.

Attitudes to alcohol are an index of character; the capacity for it too. One of Hemingway's complaints against Fitzgerald was that he got drunk too easily; whereas to him, Hem, downing the hard stuff was healthy and normal and "a great giver of happiness and well-being and delight" (and even helped his shooting), to Fitzgerald it was poison. There's a macho subtext to this: holding one's drink as a proof of manhood. Hemingway and Cheever liked to boast that they could drink anyone else under the table, as though their failure to become intoxicated was a mark of strength rather than part and parcel of addiction.

Ernest Hemingway pouring himself a shot of liquor. Photograph: Tore Johnson/Time Life Pictures/Getty Images

Alcoholism isn't easily disentangled from mental-health problems. "Madness & booze, madness & booze,/Which'll can tell who preceded whose?" says Berryman in one of his Dream Songs. But altering one's mindset is vital to creativity, and booze can help with that, Bukowski claimed – "it yanks or joggles you out of routine thought and everydayism." Hemingway thought so too: "What else can change your ideas and make them run on a different plane like whiskey?" They have a point. There's a window between the first and second drink, or the second and third, when the unexpected sometimes happens – an idea, an image, a phrase. The problem is getting it down before it's lost; if you're in company, that means disappearing with your notebook, which takes resolve or self-regard. The Amis principle – a glassful to relax with at your desk when most of the writing has been done – is fine for those with will power. But there's the cautionary example of Jack London, who used to reward himself with a drink when he'd done half his daily quota of 1,000 words, then found himself unable to get started without one. The man takes a drink, then the drink takes the man. Liberation becomes stupor. "Write drunk; edit sober" is Hemingway's much-quoted advice. But the rat-arsed aren't capable of writing. After a point, the crutch becomes a cudgel.

Why do writers drink? Why does anyone drink? From boredom, loneliness, habit, hedonism, lack of self-confidence; as stress relief or a short-cut to euphoria; to bury the past, obliterate the present or escape the future. If Olivia Laing's entertaining book fails to come up with a simple answer, that's because there isn't one. To the literary biographer, binges and benders are a godsend – a chance to recount lurid anecdotes under the guise of earnest psychoanalytic enquiry. But for the rest of us, the words on the page are what matter. And most of them get there despite the drinking, not because of it. "Drank like a fish, wrote like an angel," would make a pleasing epitaph. "Drank like a fish, wrote like a fish" is more likely.