Academic critics of Dryden or Pope were not in the habit, the last time I checked, of interspersing their monographs with reminiscences of sex clubs in Manhattan. An affectionate excursus on that subject in Mark Doty’s What is the Grass announces that this is no ordinary piece of literary criticism. ‘And your very flesh shall be a great poem,’ wrote Doty’s subject, Walt Whitman, who, one suspects, wouldn’t have minded a bit. Perhaps best known for his 1993 collection My Alexandria, prompted by the AIDS pandemic, Doty is one of the most compelling modern singers of ‘the body electric’ and in What is the Grass he has produced an elegant meditation on the great founding father of American poetry. Not only did Whitman’s example fire up the democratic modern lyrics of W C Williams and Allen Ginsberg; it also licensed poets to place themselves centre stage in their prose, from Adrienne Rich in What is Found There to Susan Howe in her prose-poetry hybrids. It is a licence that Doty seizes on greedily.

‘There is one story and one story only,’ wrote Robert Graves, and for Whitman there was essentially one book and one book only. Leaves of Grass was first published in 1855 and obsessively revised throughout Whitman’s life, with the final edition being published when he was on his deathbed in 1892. ‘I celebrate myself, and sing myself’ begins ‘Song of Myself’, but the self is also a collective, since ‘I am large, I contain multitudes’. It is also a distinctly, scandalously queer entity. Never has a poet’s eye been more alive to the beautiful passing stranger: ‘I love him, though I do not know him,’ Whitman says of a fleetingly glimpsed wagon driver. Whitman was and wasn’t a gay poet, Doty argues, since the label didn’t exist in the 1850s, though readers of lines like ‘Something I cannot see puts upward libidinous prongs,/Seas of bright juice suffuse heaven’ will have drawn their own conclusions. Whitman even claimed to have fathered six children in his twenties, perhaps during his own era – like the youthful Doty’s – of ‘trying on heterosexuality’.

Whitman’s aesthetic of intimacy is replicated in Doty’s engaging memoir. We are offered a painful account of a youthful marriage to an older woman, before a gay awakening and some outdoorsy self-discovery, described in the style of Whitman’s ‘Calamus’. Counterpointing this are Doty’s readings of Whitman via the five sources of his art, from spirituality to mortality, though Whitman the gay prophet holds Doty’s attention in ways that the Yankee sage and Civil War laureate of Drum-Taps evidently does not.

Not everyone cared for Whitman’s fleshy frankness back in the day. Doty cackles along to contemporary judgements, such as Rufus Griswold’s (‘It is impossible to imagine how any man’s fancy could have conceived such a mass of stupid filth’). Victorian prudery aside, though, the case against Whitman is easily made, with D H Lawrence’s hatchet job in Studies in Classic American Literature still holding up amusingly well today. When Whitman sees someone suffering – a beggar, a prostitute – he says not ‘I can help you’ but ‘I’m just like you’. But the problem is, a lot of the time, he’s not. The empathetic fallacy, to call it that, is really a fig leaf for self-aggrandisement, or self-deception. ‘Walt was really too superhuman’, Lawrence tut-tuts, and ‘the danger of the superman is that he is mechanical’. Doty confronts the limits to Whitman’s purported universalism in his comparison of freed slaves to baboons and his reduction of women, in Lawrence’s words, to ‘a function’, namely childbirth.

In Leaves of Grass, Whitman’s cult of personality was already up and running before the reader reached the first poem, in the instantly recognisable portrait engraving of the bearded bard at the front. Doty recounts how, for the second edition, Whitman requested that this be altered to give him an enlarged crotch. Today, it could be his Grindr profile pic. Bram Stoker wrote a fan letter to Whitman in which he seems to be angling for a date (‘I am six feet two inches high and twelve stone weight naked…’). Stoker proselytised zealously for Whitman’s work, which, even in bowdlerised form, struck British readers as an American offshoot of Dante Gabriel Rossetti’s ‘fleshly school’. Stoker did meet Whitman, but can’t have experienced his magnetism as entirely positive if we are to believe the claim that he went on to base the character of Dracula on the American poet. (This might be the moment, given Doty’s mangling of the plot of Dracula, to point out that the book contains numerous unfortunate repetitions and mistakes.)

Doty is insightful on the promiscuous range of Whitman’s vocabulary (‘gulch’, ‘hankering’, ‘I guess’, ‘woolypates’, ‘foofoo’, ‘squaw’) and the irresistible transgressive force of the poet’s rangy lines. In a passage quoted by Doty, Herbert Marcuse argues that smoking marijuana brings ‘extra-societal insights’ in ways that getting drunk does not, because of the effort required of the dope-smoker to stand outside conventions and laws. In form as well as content, Whitman’s work thrills with its ‘extra-societal insights’ about the queer body at the moment of its birth for the modern reader. Doty returns to memoir in the closing section, with an account of a motorbike accident and its complex aftermath, before supplying a happy ending of sorts. What, Doty wonders, paraphrasing Rilke, does being on earth ask of us? Simply to become poetry. He turns to ‘Crossing Brooklyn Ferry’ to flesh out this audacious claim, treating us to one last buttonholing from Whitman across the generations (‘It avails not, time nor place – distance avails not,/I am with you, you men and women of a generation, or ever so many generations hence’). Lawrence called Whitman a poet with ‘his privacy leaking out in a sort of dribble, oozing into the universe’. But Doty helps us feel the touch and connection of great art afresh. It is a warmly affecting performance.