About a Boy by Nick Hornby Gollancz, pounds 15.99 No More Mister Nice Guy by Howard Jacobson Jonathan Cape, pounds 15.99
Nice guy, nasty guy; good cop, bad cop. What have we here? Blurb- wise, it's easy: two Bloke Books. Bloke A, heading for 40, finds he's a surrogate father without trying. Bloke B hits 50, whop!, venery's demise, bum's rush, goes ape. Bloke books, right? Mutt and Jeff. Cultural phenomenon sort of stuff. Right?

So. Nick Hornby. Everyone's agreed about him: the Bloke author, a sort of North London literary Vivaldi: sleek, well-achieved books for men who sort of don't really like book stuff. You know: book stuff. But they'll be all right with Hornby. Cropped name, cropped hair, denim shirt, football, pop, the great apologist of male emotional inarticulacy. Sort of stuff.

Except About a Boy is not just about inarticulacy; it's about utter purposelessness, too. The narrator is called Will Freeman, but we shouldn't read too much into that; there was some gossip to the effect that he was originally going to be called something else, except there turned out to be a real Mr Something Else who kicked up a stink.

He didn't, curiously enough, want to be in a Nick Hornby book, but you can't blame him because Will Freeman is an arse. Lives in a minimalist flat in Islington: kitchen gadgets, CDs, film posters, but no scary books, no scary feelings. No job, either. Doesn't need one, living as he does off the royalties from the Christmas novelty song his father wrote. He's cool. Sub-zero cool, according to a men's magazine quiz. "When he got home he put a Pet Shop Boys CD on and watched Prisoner: Cell Block H with the sound down. He wanted to hear people who didn't mean it, and he wanted to watch people he could laugh at."

Cool. But not for long. He invents a non-existent child so that he can join a single parents' group and pick up the lone mothers, but Nemesis desultorily scratches her fanny (can't be bothered to do the full job) and, by a series of interlocking coincidences, irrupts geeky 12-year-old Marcus and his hand-knitted depressive mum, Fiona, into Will's not-really- a-life. Consequences: Will engages a little bit with the world and gets to have some meaningful sex (with Ruth, a tangle-haired book illustrator who says interesting things, although we don't get to hear any of them). Solemn, clever Marcus finds out who Kurt Cobain is, makes friends with 15-year-old wild child Ellie, and develops a strategy for self-protection outside the nuclear family; Fiona only tries to top herself once.

Looked at like that, the book is like Will's flat: glossy, cool, but empty. Hornby goes beyond his role as Bloke Apologist and takes on the mantle of Tetzel, flogging Bloke Indulgences. You can be a frozen infantile popster and trashmonger, but don't worry, the kids'll survive, they'll get what they need, you can stay a teenager for ever, mostly. Every adult in the book has fucked up beyond all recognition, and yet it all turns out reasonably sort of OK once Marcus has been got over the hump with the aid of an older Bloke Mate and a Nirvana T-shirt.

The moral of the story is an agreeable smooth balm for the solipsistic disengaged. Disconnection lies at the book's heart, not only in the characters but in the structure. About a Boy reads as though it's a novelisation of a screenplay, as though wired together on one of those computer programs that do your story for you. Hero's ghost from the past? Check. Seven-step plot breakdown? Roger. Plot-point at end of Act I: um... the kid's mother takes an overdose?

You can see Hornby's problem. Having lumbered himself with a cipher as his main character - a man utterly without desire, engagement or motivation - he finds himself having to steer a tricky path. He can't keep things going by wheeling on a whole pantheon of dei ex machinae, but nor can he rely on realism, which would just lead to dull Will sitting in his room listening to CDs and occasionally popping out for a poke.

The result is that everything gets loaded on to poor Marcus, who becomes an exaggeration, almost a grotesque, having to drive the story but not wholly allowed to be the hero because he's not - nor will he ever become - a Bloke. And Blokes won't read books about 12-year-old boys. There is a story worth telling in here, but Hornby hasn't allowed himself to tell it, surrounding Will and Marcus instead with a cast of strangely-cliched walk-ons and rather static set pieces.

It kept reminding me of something: the people who walk in at just the right moment, the careful predictability of structure, the interchangeability of the minor characters, the remarkable hospitality of the book's world to the utterly undeserving. And then I realised that it was in essence the ultimate Bloke World, the universe of pornography.

Which is a word you'd more immediately think of in connection with No More Mister Nice Guy. Plot? This isn't about plot. This is about an eruption. Jacobson's hero, Frank Ritz, needs a big injection. Plot? He's just gone ape, standing there bollock-naked, flailing his giant tumescent intelligence around his head and bellowing like a prophet. This is real bloke stuff, Jewish bloke stuff, and how insipid it makes the North London putative blokes look, with their Gentile gentility, their football and their CDs and their thin, polite Bloke sex.

If there is a plot, it's a variation of Orwell's Coming Up For Air, or the sort of picaresque mid-life reassessments that Leslie Thomas goes in for, or a boiling hissing mixture of either, or both, and Portnoy's Complaint. No More Mister Nice Guy is driven by a tumescent passion, leaps in open-fisted, wild-eyed, present-tense, roaring. And such roaring. Jacobson has always been a linguistic virtuoso, but under the pressure of this book's theme - time running out, doors slamming, what now, what next - his effects are more reckless, his control more precise.

It's a joy to watch the mad staring-eyed bastard at work, even when he's being relatively muted, setting out his leitmotifs: "He remembers his grandfather smiting his forehead whenever his grandmother opened her mouth. And didn't his father do the same? Woman - mouth - speak; man - forehead - bang."

And so we're off, as Frank, expelled from his house by bulimic Mel ("I don't mind that we don't fuck every morning, I don't mind that we can't talk to each other any more... I mind most that we don't play together any more, that there are no more jokes") hits the road in search of... what? Apparently aimless, his physical and mental wanderings take him on a grand tour d'horizon of his erotic past and into a flaccid and acquiescent future. The all-time great lay, the betrayed friend, the language students, the fat comedian with whom he lies chastely in bed, eating black chocolate and drinking beer; the rage, the priapism, and what for? "Woman - mouth - droop; man - forehead - bang." Language reduced to signal-flags; dick-driven, cunt- struck, last-resort ape-speak.

There's more, of course; riches more. Jacobson is a prophet, not a preacher; he never tells, but shows. Yet, vast as the gulf is between Jacobson's ranting, bursting, forehead-banging Mr Nasty and Hornby's reluctant, tepid, bloodless Mr Nice, common themes emerge. Both Frank Ritz and Will Freeman live fundamentally vacuous lives. Neither has children, though Ritz has a possible by-blow and Freeman his self-elected surrogate. Both are mistaken about their own sexual nature, Ritz realising he's a masochist and Freeman discovering "meaningful" sex. And neither does useful or dignified work. Freeman has no work at all, and Ritz only works at two removes from the world, as a weekly television critic.

Neither seems able to connect with women except as purveyors of bodily fluids, unless the woman is desexualised entirely: in Freeman's case it's Marcus's mother, a frizzy-haired depressive music-therapist; in Ritz's, the comedian, made literally sexually inaccessible by a great apron of belly-fat.

If two such different writers are both telling the same story about men, what does it mean? Coincidence, surely. Unless it's true that modern urban man has become a mere doomed life-support system for his time-limited tools, capable only of functioning in isolation unless forced, disconnected, trivial, emotionally knackered, dumb, without dignity, pointless... in which case, I'm glad I'm not a... hang on... no... need to think about this... no... bugger off... leave me alone...