Blood, guts and fighting are Chuck Palahniuk's fascinations. The writer of Fight Club thinks that men need to reclaim masculinity - with their fists. But, Dave Hill finds, he's really just a softie at heart.

Sentiment does not gush into the soul when reading the novels of Chuck Palahniuk. Fight Club, the bruising debut that made his reputation, concerns guys beating seven shades out of each other in the name of personal growth. Survivor, his second book, centres on the only member of a death cult left alive following a mass suicide. His latest, Invisible Monsters, enters the psyches of men, women and others balanced somewhere in between, who run amok in the cultural china shop where catwalk fashion, sexual transgression and the grim realities of "gender reassignment" meet.

In these latest thrumming pages we make the acquaintance of citizens with half their faces blown off or leafing eagerly through catalogues of surgically pre-fabricated vaginas. In all his books the prose of Palahniuk - pronounced "paula-nick" - is hard and glittering, his sentences dark diamonds of bleak insight and unforgiving parody. But hark: he knows of harmony, of tenderness, of love. "All of the books," he explains, "are just a very, very cynical way of getting to a sentimental place."

As ever with creativity that amplifies awfulness in order to uncover something finer and braver, Palahniuk's stories have suffered from dimwitted misinterpretations. For example, David Fincher's funny and powerful film version of Fight Club was denounced in some quarters as an advertisement for fascism when, if anything, it might be read as a warning about how a certain form of idealised masculinity can manifest itself in slavish, martial forms.

Palahniuk's characters are always on the run from all that is bland and predictable, soporific and safe: Ikea furnishings, career conformity, obedient consumerism, being dumbly beautiful for a living. What does it say, though, about his vision that his first evocation of a revolt against convention principally depicted men learning how to use their fists on one another?

"Fight Club came out of something that all my peers talked about," he says. "It is that their fathers had never taught them what they needed to know about becoming men. And what I'm learning more and more is that these fathers had not been taught by their own fathers."

The book is also informed by knuckle-on-bone experience. Palahniuk, 38, spent several frustrating years trying to make it as a writer of some kind. He worked on trucks by day and went to bars by night where sometimes he became involved in dust-ups.

What he derived from these encounters is the curious thing we all learn when we see boxers embrace at the finish of a bout: that a physical contest can also bind the protagonists in mutual respect. Palahniuk is certain that there are some things in life that men innately enjoy and should be given - given back - cultural permission to express. "If we try to suppress that completely, it is going to erupt in some horrible uncontrolled way. In a culture where we have condemned all forms of violence as invalid and not needed, violence still comes up. It comes up in hyper-violent ways, like in school shootings."

The notion that men must be allowed to be men or else all society - women included - suffers, is consistent with the mantras of the American men's movement and the mytho-poetic prescriptions of its patron saint, Robert Bly, the author of Iron John. Palahniuk also seems in sympathy with the argument that conventional manly virtues have been done down in the keyboard-driven, postindustrial economy, and he has not missed the irony that while men's interest in violent sports today causes concern, women's incursions into the same territory are often applauded. So when men box it is mindless violence and when women box it is liberation?

"Right."

For Palahniuk the male protagonists of Fight Club are human spirits in revolt against the deadening destinies society that allots them. Many of his friends are teachers and, like teachers here, they often com plain that education is increasingly about schooling children for niches rather than educating them to create their own place in the world: "They're taught to accept the world the way it is. I felt that all of my schooling was to get me a good corporate job so I could be a good corporate citizen, pay my taxes, live politely and then die."

Where Palahniuk was concerned, the system seems to have failed. He has written his own life script instead. He grew up in a trailer in the desert, the part that lies in east Washington state: "Cactus and sage brush and coyotes. We were really, really poor."

His mother was an office manager, his father worked on the railroad which came in handy because whenever a freight train was derailed he was the first to know. Some of Palahniuk's most vivid childhood memories are of stealing out en famille at dead of night - he has a brother and two sisters - to pilfer from the train-wreck.

It is a story that he makes use of in Invisible Monsters, when one of the characters looks back on a past she is desperate to escape.

A thick vein of such dark comedy pulses through his writing. His mother now works in a nuclear- powered factory, and he savours her tales of radioactive mice penetrating the confectionery machines. His father is dead - murdered 18 months ago along with a woman he was dating. The trail of the woman's former husband, who had, allegedly, been threatening to kill her for three years, has just been picked up. "My father walked in on the end of a chain of events. He happened to be the unhappy man who had answered her personal ad in a magazine."

Palahniuk thinks that personal catastrophe and conflict can deepen human relationships and make us richer as people: the blood of the fight-club floors, the drug-deranged odyssey of self-mutilation that powers Invisible Monsters. His character, named Brandy Alexander, dazzlingly suspended midway between sexes, lives out a kind of makeover that goes more than skin deep.

The novel's narrator is his first in a female voice and addresses the questionable premise underlying Fight Club - that men and women are fundamentally different kinds of humans and that those differences are finally decisive. However, Palahniuk was surprised by the reaction of women to his book. "I used to believe Fight Club was a men's phenomenon. But I got so much response from women saying that they want that form of expression for themselves. They, too, respond to the notion that sometimes you must destroy if you are going to make things better."

All of this suggests a different way of making sense out of today's gender flux and clutter. If masculinity means guts and vigour, and a passion for controlling your own destiny, then it is not so much an essence exclusive to one sex as a metaphor that both sexes can make use of. And if emasculation means the numbing of the senses, then it is a menace to everybody, men, women and all.

· Invisible Monsters is published by Vintage, £6.99. Chuck Palahniuk is giving a series of readings throughout the country from today. Details: 020-7840 8688.