Books: The escaped Valley boy whom Brian Eno attacked with a stick

Founder of the Velvet Underground, and musically vital ever since, John Cale has written his autobiography as an anarchic assemblage worthy of his life. Designer Dave McKean fills the book's cardboard covers with photos, comic strips, subliminal and overt repetitions and transformations of images, and shapes each block of text. He stops you from ordinary reading, keeps your brain skidding on the page, even as Cale's terse, achingly honest recollections, in partnership with New York underground chronicler Victor Bockris, race on. The book, in other words, is the product of a three-way collaboration. Cale has attempted to uncover the core of himself by working with others. It's how he has lived his whole life.

Cale was born in Garnant, a small Welsh mining community, in 1942. He spoke only Welsh till he was seven. His father spoke only English. So it was his mother, a vibrant educationalist, who shaped him. Her presence beside him as he learned the piano was formative; it began "a life-long reliance upon a collaborator to complete not only the work but me". Her seeming distance after a mastectomy was just as crucial. It was in the space between such presence and absence that Cale's creativity was born. Fuelled by the community around him, he knew he had to leave it. Listening to John Cage, Ornette Coleman and Elvis, New York was the city of his dreams. He became a minor musical prodigy, and conned his way to America, aged 21. He had escaped and arrived, all at once.

His subsequent life can be seen as a series of shed skins. One minute he's working with La Monte Young; the next, he's with Andy Warhol. Look again, and he's wedded the avant-garde to rock, with the Velvet Underground. Before you know it, he's a West Coast A & R man; then a solo artist in pre-punk London; then struggling back in New York. The music never stopped. In LA, for instance, came the beautiful, desperate Paris 1919. He also became an accomplished performer. As a music student, he attacked a piano with an axe; as a proto-punk, he axed the head off a chicken and hurled it at the crowd.

But through all this frenetic movement, and an openness to collaboration almost unique in rock music (with Patti Smith, Terry Riley), Cale's childhood wish for completeness still nagged. He moved through destructive marriages with desperate fatalism. It was a weakness mirrored in his work. Some collaborators bullied him. Brian Eno attacked him with a stick. The careful fairness, even puzzlement, as he describes these episodes precludes special pleading, They show this gifted man as a younger brother in his partnerships, an eager-to-please son; his mother's child.

Symptomatic is his relationship with Lou Reed. A photo of the ad hoc, 1965 touring band which brought them together reveals Reed as a wide-eyed, unhip wannabe; Cale, the same age, but already a downtown veteran, looks bored. But they became soul-mates. They bonded over books and smack-broken veins. Each helped to complete the other. Though their talents were equal, Cale's deference to his partner was remarkable. Still, Reed sacked him from the Velvet Underground. The pair's 1990 reunion Songs for Drella showed their perfection as collaborators; its aftermath, when Reed tried to remove Cale's name from the record and, when the Velvet Underground reformed, destroyed it anew, tore their bond, seemingly for good. And yet Cale pines. Every time you think Reed must surely be gone from the book, he's mentioned again. Like less troublesome loved ones (Nico, Warhol, Sterling Morrison, all dead, all wrenching losses to Cale), Reed's absence is a presence in the book. It itches like a sawn-off limb. As with his mother, Cale can't let it go.

What's Welsh for Zen has other uses. It's a gossipy cultural history of the New York avant-garde, including explanations of harmonic innovations with La Monte Young, and the drug-dealing that financed them. It portrays passing acquaintances with a capacity for colourful reinvention - snipers, secret agents, gamblers and gangsters. But it's finally an exploration of why Cale has worked and lived as he has. "I'm getting sadder and sadder thinking about my lack of self-knowledge as I write this book," he says. "I'm distraught about my lack of any sense of my own worth." It's a work much like his disparate, yearning records; an attempt to question through art. The difference is that this book is a guide to the emotional constants which have caused his creative questing. In writing about Wales, and his mother, and the Velvet Underground, he has tried to uncover his roots. It's as if he wants to start his escape again.