David Foster Wallace hanged himself in the autumn of 2008, leaving a dense, agonised, brilliant and moving body of work. What was already a more than usually cultish following for a living American writer entered, as the publication puff for this biography vulgarly boasts, the territory of a Kurt Cobain or a James Dean.

A biography of this sort, then, is to be greeted with caution. More often than not, any such writer’s first biographer – so soon after the fact, under the presumed pressure to publish as quickly as possible – will make a hash of things. D T Max does not. Barring the odd organisational clumsiness, this is a fine piece of work: detailed yet economical, shrewd and subtle about the writing, and detached enough about the life to make clear, from time to time, that this candidate for secular sainthood could also be a jerk.

Wallace wrote and lived like someone who had become consumed by his own themes: media supersaturation (for Wallace it was television, though as Max points out he’s been posthumously claimed for the Internet generation); the scrambling of high and low culture; the moral imperative and extreme difficulty of paying close, continuous and loving attention to the right things amid a blizzard of distractions and addictions.

Wallace’s recursive, doodling sentences, his self-consciousness, his goofy and sometimes childish pot-head humour, his emotional lability – all had about them a distinct and deliberate air of the teenage slacker. The images that survive of him – long-haired, wide-eyed, stubbly, wearing T-shirts, unlaced hiking boots, flannel shirts and the bandanna which he told a friend’s child was to prevent his head from exploding – cemented that image.

When Wallace – then an admired but not yet famous first novelist – arrived at Amherst to teach creative writing, ‘the students who showed up for his first day of class were surprised to find a man barely older than themselves, carrying a pink Care Bears folder and a tennis racket’. There’s an open question as to how contrived all this was (he took a New York Times interviewer to a friend’s house to eat KFC and watch The X-Files) but then, what could be more teenage than anxiously fashioning your own image?

Wallace had the disgusting habit of drinking coffee with a tea-bag dunked in it, and he liked to let his pet dogs lick food out of his mouth (‘they pretend they’re kissing you, but they’re really mining your mouth for food’), which was only mitigated by another habit of keeping a toothbrush in a Ziploc bag in his sock and incessantly brushing his teeth. Left to his own devices, even as an adult, he lived almost entirely on Pop-Tarts and had not the slightest feel for domesticity. His natural habitat was a black-painted room with wet towels draped on every available surface (Wallace suffered panic attacks and prodigious perspiration, hence the bandanna).

But, this perpetual teenager was also, of course, an astonishingly gifted and thoughtful man: the casual self-consciousness of the adolescent translated into the painfully inescapable self-consciousness of a brilliant mind gnawing on itself. Max’s sympathetic account of Wallace’s life aches with the sense of a man who found it incredibly hard just living day-to-day in the world.

The parts describing Wallace’s breakdowns, his passage through alcoholism, drug addiction, and the pull of suicide are just agonising (anyone completely surprised by his end hadn’t been reading his work all that closely). ‘The Bad Thing’, as he called depression, left him completely unmanned. One family rescue mission found him ‘lying on his couch under blankets. His eyes were glued to the TV and he refused to drink or eat. A pot of weeks-old chilli sat on the stove, and the computer that he’d brought to Arizona was still in its boxes. He said he’d befriended a tarantula on his back porch.’ Max makes clear how ill Wallace was for most of his life, and how risky self-medication and attempts to get off his antidepressants were.

The life goes from happy Midwestern childhood through awkward, sweaty adolescence to a version of the standard Ameri-can writer’s life – grants, teaching jobs, retreats, advances, journalism, publicity and the flight from it – twisted and interrupted by mental illness. Wallace inherited his mother’s obsession with grammar (and repaid her with the unkind portrait of Avril Incandenza in Infinite Jest), and played tennis well though not as well as he sometimes gave out. He fell promiscuously and sometimes obsessively for women, and didn’t always treat them well. At one point he tried to obtain a gun with a view to killing the husband of the woman he was obsessed with. Later he tried to push the same woman – the poet Mary Karr – from a moving car. On another occasion he threw a coffee-table at her. He finally found some sort of peace with his wife, now widow, the artist Karen Green.

Above all he wrote – in great gouts, which often made the immediate acquaintance of the wastepaper basket. Max reports without apparent scepticism a claim that Wallace some days wrote 25,000 words. I’m not sure that’s physically possible. The account of the process of editing Infinite Jest down to its current, only barely manageable size is fascinating.

Wallace was delicate and open, but also competitive. As Max makes clear, the path to his mature style involved a series of literary parricides – starting with the almost impenetrable undergraduate thesis in philosophy, in which he sought to rebut the austere logic of Richard Taylor’s fatalism. Wallace’s renunciation of irony – as a defence against the world that ended up being a trap – was a repudiation of the McInerney–Easton Ellis generation. He had to fall under the spell of, and then turn against, the metafictions of Barth and Pynchon (reading the latter, at first, had been ‘like Bob Dylan discovering Woody Guthrie’). He had to see off Updike.

Max has a keen and sensitive turn of phrase when it comes to Wallace’s style: ‘layers of asserting and then hedging those assertions to assert slightly more emphatically and imaginatively’; ‘an odd combination of a mimic and engineer’. Sometimes he goes over the top – ‘In Infinite Jest, Wallace was proposing to wash Pynchonian excess in the chilling waters of DeLillo’s prose and then heat it up again in Dostoevsky’s redemptive fire’ – but still he captures something. Of the magazine work, he writes that its voice was ‘the tone of a sensitive, sincere genius operating in second gear’ (though for an American magazine journalist Max is surprisingly forgiving of how much, and how obviously, Wallace simply made stuff up).

It seems miraculous, even heroic, that Wallace achieved what he did. Whatever their faults, Infinite Jest and The Pale King speak to and about us in ways that no other work has before or since. Few books have made me laugh or cry as hard. As D T Max argues, when talking about a pivotal early short story, ‘He began to take the key step of universalising his neurosis’. This is a tricky pass – Wallace hardly had a normal relationship with television, let alone life – but it is the very intensity of his engagement that seems to permit it.