Born: 18 December 1943, Dartford
Educated: Sidcup Art School
Family: Originally partnered Anita Pallenberg; three children Marion (b1969), Tara (died in infancy), Dandelion (b1972). Married Patti Hansen, 18 December 1983
Career: Guitarist and songwriter for the Rolling Stones. The band was formed in 1962, with Mick Jagger (vocalist), Bill Wyman (bass), Charlie Watts (drums), Brian Jones (rhythm guitar) plus Ian Stewart (keyboards)
Albums with the Rolling Stones: 35. The first was 1964's The Rolling Stones, the most recent was No Security (1998)
Solo albums: Talk is Cheap (1988); Main Offender (1992)
Films: Sympathy for the Devil (1969; Gimme Shelter (1970); Ladies and Gentlemen, the Rolling Stones (1977); Let's Spend the Night Together (1983); Hail, Hail Rock'n'Roll (1986); Flashpoint (1991)
On his past: "When I was on heroin, I learned to ski and I made Exile on Main Street."
Nickname: The Human Riff
On his present: "I wanna do it like Muddy Waters did, till I drop."
Thirty years upon the stage/ I hear the people say, 'Why won't he go away?'" The line is from "I'm Dead (But I Don't Know It)", a typically merciless new song by Randy Newman that addresses the now staple theme of rock'n'roll wrinklies who won't do the decent thing and disappear.
For the Rolling Stones - avatars of rebellious Sixties youth who couldn't see themselves playing rock'n'roll beyond 30 - the vexing issue of age is one that has followed and haunted them for the greater part of their career.
"I wanna do it like Muddy Waters did, till I drop," Keith Richards told me on the eve of the Bridges to Babylon tour that finally hits Britain yesterday with a concert at Edinburgh's Murrayfield Stadium. "I have no reason to stop. I enjoy it. That's what I'm good at, and I'll do it without an audience if I have to. I always think of it in those terms, the same as knowing the psychology of what goes on in the music business and kind of understanding it. Because no band has ever survived this long, the actual emphasis is on the longevity and the survival. We could have written all the jokes ourselves. I wish anybody my age was in my shape."
Them's fighting words, and they're what we've come to expect from the old road warrior who's always been the heart and soul and guts of "The Greatest Rock'n'Roll Band in the World". But exactly what shape is Keith Richards in, after a lifetime of drug abuse and gnarled guitar riffs? More to the point, how come he's alive at all, when sturdier men have been felled in their prime by the extracurricular activities for which he is notorious? (And, by the way, wouldn't he in fact be a lot cooler if he were, you know - dead?)
The Rolling Stones have always been polarised between Mick Jagger and Keith Richards: Jagger the greedy, social-climbing "face" of the Stones, the rubber-lipped Narcissus you love to loathe; Richards the skeletal spirit of rock'n'roll on leather legs, indifferent or oblivious to money and fame. At least, that's how we've been set up to see them, mainly by a music press quick to distrust shameless exhibitionism and even quicker to celebrate the dark genius of the sidekick in the shadows.
Both Jagger and Richards were born in Dartford, Kent; Richards on 18 December 1943, Jagger the following July; and both went to the same primary school. Bonding as blues-besotted teenagers in the late Fifties, they formed the Stones with Brian Jones in 1962. By 1964 they were every mum's worst nightmare of delinquent youth, a punk counterpoint to the mop-top wholesomeness of The Beatles. Their songs were soaked in black Americana, and it was only a matter of time before they were recording at the legendary Chess studio in Chicago. After an unconvincing flirtation with flower power, they hit their real stride with the astonishing sequence of albums that began with 1968's Beggar's Banquet and climaxed with the magnificent double set Exile on Main Street (1972). The fact that this period coincided with Richards' descent into full-tilt heroin addiction only makes his achievements - the anchoring of the band in his playing and his debauched, malevolent persona - the more incredible. Exile, recorded in the French mansion where he and his charismatic consort Anita Pallenberg (by whom he has two children) held court, was never to be equalled in all the years that lay ahead for the Stones.
But here's the real point: Keith Richards has managed to extract more soul and poetry from the electric rhythm guitar than anyone else in rock's history. Richards' riffs - from the Pop Staples slither of "The Last Time" through the eerie glassiness of "Gimme Shelter" to the cranked combustion of "Start Me Up" - are so viscerally "right" that they almost transcend rock'n'roll altogether. We keep coming back to "Satisfaction" and "Stray Cat Blues" and "Monkey Man" because no one - not Steve Cropper, not Jimmy Page, and certainly not Joe Perry or Slash - has ever made brute guitar chords sound so demonically sensual. Richards took the boxy, compact riffing of Chuck Berry and turned it into something loose, menacing and intensely sexual.
We stay loyal to Keith Richards - or, at least, to the idea of Keith Richards - because he continues to embody the dirty glory that fired the Stones' finest hours, from The Rolling Stones (1964) to Exile on Main Street eight years later. Around him swirls the mega-circus that is the Bridges to Babylon tour, cocooning him in its giant pod; behind him flap the logos of the tour's sponsors (Tommy Hilfiger in America, Castrol GTX in Britain). Does he care? Should he care more about Mick Jagger's unapologetic mercenariness?
Somehow none of it seems to touch him. When he shuffles up to the lead microphone to sing the sneeringly bitter, hopelessly tender "All About You", isn't he simply lost in his music?
"When you're up there, you're always doing the same gig, basically," he says. "And you're hoping to get to that place where your fingers are doing things you know they can't do. When you surprise yourself, you rise about three feet off the ground and you see Charlie Watts rising above his drum kit, and for a minute you get that buzz where a band just gels for a magic few moments. I don't know; you ask yourself who you're playing to. You don't want it to be nostalgia alone, but there's a lot of people who don't want to hear a new song. You're always riding that fine line between unfamiliarity and not wanting to turn into the Beach Boys."
To his credit, Richards doesn't pretend that 98 per cent of the punters who turn up to a Stones show aren't there for primarily nostalgic reasons - or because they think they "ought" to feel nostalgic about this fossilised freak show. He knows full well that the Stones can never again have the galvanising impact they had in their late Sixties/ early Seventies heyday, when the satanic majesty of their music voiced the turmoil of the times in ways no one else managed to do. Nor does he strive desperately to keep up with changing fads and fashions, as Mick Jagger does. Where Jagger butters up younger generations - unsuccessfully - Richards pulls no punches when it comes to vociferously dismissing bands such as Oasis.
Which brings us to the small matter of the inordinate amount of sub-par music the Rolling Stones have made since their unquestionable masterpiece, Exile on Main Street. What is it about Richards that he allows such bilge to be issued in the name of a once-great band, and can we forgive it? No, but we can point to the fact that when the circumstances have been conducive - when he and Jagger haven't been feuding, or he's been left to his own devices - Richards has delivered the goods in spades. His 1988 album Talk is Cheap is an overlooked marvel, a feast of supercharged funk, craggy soul balladry and ripped rock'n'roll, and his solo outings on Stones albums such as Steel Wheels, Voodoo Lounge and Bridges to Babylon ("Slipping Away", "Thru and Thru", "Thief in the Night", "How Can I Stop") have been a squillion times more affecting than Jagger's cod-soul posturings.
What does seem to have gone by the wayside in recent years is Richards' ability to summon a decent uptempo riff from his fretboard. Rockers such as "Love is Strong", "Sparks Will Fly", "Lowdown" and "Flip the Switch" are as redundant as the hoariest offerings of, say, Foghat or Molly Hatchet, empty of real drive or energy. But then, is it any wonder that a man in his fifties is going to have a job writing riffs that articulate the swagger and the anger of youth? For surely that's the central problem here. We don't object to a silver-maned Burt Bacharach revisiting "Reach Out For Me" or "Trains and Boats and Planes", but we'd rather not have to see a bare-chested, apparently anorexic Jagger and Richards clinging to their past on the cover of Rolling Stone.
"The thing that rock'n'roll used to do to you as a kid was make you sorta feel tough," says Randy Newman. "The Rolling Stones sort of embody that, and yet you could blow Mick Jagger over with a feather. Musicians aren't tough. It's artifice. There haven't been five tough musicians in history, and they're doing all this posturing and sneering and snarling. And that's fine, that's what you do. 'Street Fighting Man', 'Under My Thumb'... I mean, how long would it take you to get out from under Mick Jagger's thumb?"
When I spoke to Keith Richards in 1997, I took the risk of asking him whether it hurt that few people took the Stones seriously any longer as a current act. For a few endearing seconds he paused, as though genuinely hurt by the question. "You get to accept the fact that you're now covering several generations," he replied eventually. "You look out at the audience and you see your whole life before you. It's not so concentrated as it used to be, and that sort of spreads the angle of who you're touching. But I find it very heartening for myself that I get a lot of stuff from 13- or 14-year-old would-be guitar players, because my theory is that the only thing you can put on a musician's headstone is 'He Passed It On'. So, personally, that makes me feel very warm."
This appeared to me to be fair enough. And who, after all, has the right to begrudge a band going out and playing to the millions of people who genuinely want to see them? It's only those of us who retain some sentimental investment in rock'n'roll as the subversive music of a tribal underground who can't buy the Bridges to Babylon tour as anything more than hollow ritual. For what it's worth, the show I caught in Chicago 18 months ago was the best Stones gig I ever saw.
"It's great to be back, great to be here," says Richards, as he introduces "Thief in the Night" on No Security, the Stones' recent non-event of a live album. "It's great to be anywhere, y'know what I mean?" Truer words the man may never have uttered.