Books: The biggest man by a million chalks: Anthony Lane on Auguste Rodin, the sculptor who created heavy drama day after day

In 1906, Auguste Rodin sliced off the ear of George Bernard Shaw. This was not some lurid sequel to the activities of Van Gogh, but pure practicality. For one thing, it didn't hurt; the artist slapped the ear back into position, although Shaw's wife, looking on, 'half expected to see the already terribly animated clay bleed'. Of all who posed for Rodin - from railroad millionaires to Cambodian dancers, from Clemenceau to a strapping Belgian soldier - none gave as vibrant an account of it as Shaw, or 'Bernarre Chuv', as the artist called him. Rodin was 'by a million chalks the biggest man you ever saw', though short and quiet, and even more heavily defended by beard than the playwright. He seemed to reserve all passion for what went on in his hands, with none left over for affectation. To get a grip on the force of his sculptures, you must study them from every angle; but they were made by a man with no side.

Ruth Butler has set out to unwrap this mystery. The Shape of Genius (Yale, pounds 19.95) is the latest in a long line of Rodin biographies and, to be frank, the most indigestible. Butler refers to 'seven years of steeping myself in the long and vivid life of Auguste Rodin'. Without wishing to cast doubt on her stamina, let alone her scholarship, one must admit that too much steeping can damage the vividness. Butler has spent so long with her head in her archives that she's forgotten to come up for air, and the prose that ensues could do with a slap in the face: 'It is difficult in the 20th century to comprehend the quasi-religious need 19th-century people had for monuments to portray the meaningful events in their lives.' And even more difficult for the 19th century to comprehend the quasi-psychological slant 20th-century writers give to the wobbly thoughts in their heads.

The style almost kills the point before it starts, which is a shame, because Butler is on the track of something useful. To what extent was Rodin a monumental artist? Public sculpture has travelled a long way from Michelangelo's work for the Medici chapel to the giant clothes-pin, say, erected by Claes Oldenburg in Philadelphia in 1976; and it is Rodin who stands, almost alone, between the two. The clothes-pin is partly a joke about grand commissions: ask me for an image to stir the hearts of the people, and I'll show you something from your own backyard. Oldenburg was cocking a snook at the past, at what he called 'bulls and greeks and nekkid broads'. Rodin had a testing time with large projects - the monuments to Victor Hugo and Balzac, The Burghers of Calais and above all The Gates of Hell - but he doubted neither the need for such commissions nor his own capacity to fulfil them. He was not a man with snooks to cock. Fulfilment, however, invariably took him further than anyone expected.

At an interim viewing of the Balzac, for example, visitors expressed surprise at the strutting, drum-bellied superfaun that met their eyes. This rose to yelps of rage on the appearance of the finished article: Rodin had draped the writer from neck to toe in a voluminous gown, and tilted him to one side. The whole thing now looked like an expanded pun on Balzac's phallic drive, famously as unstoppable as his fiction. Being Rodin, he had needed to understand the figure beneath before covering it up, although to people outside the trade that sounded like a waste of time. They thought (as we do) that Rodin was ministering to his own expressive needs, not to the glory of his country; but in truth, he was probably the last artist who saw no reason to distinguish between the two. He adored France, and refused to take sides in the Dreyfus case. The young Vita Sackville-West, full of old English tolerance, called him 'rather a commonplace little French bourgeois', as if such qualities were inimical to art.

Ruth Butler, more respectfully, traces those qualities to their source. Born in Paris in 1840 to parents of modest means, Rodin failed three times to enter the sniffy Ecole des Beaux-Arts, which was a blessing, and hung around instead at the medical school and the zoo, where models struck no poses. From these bare necessities came both his industry and his aversion to mere show, to the 'fla-fla decoratif' turned out by contemporaries. The modelling skills acquired in his youth - making ornaments for clocks, drawing in ceramic paste at the Sevres factory - would never desert him. Even at the peak of his fame, he began each work with a handful of clay, like God on a good day.

The moral question, which this book prowls around but never attacks, is whether he also treated living people as lumps. With women, Rodin was somewhere between a worshipper and a pouncer: always a dangerous combination. Butler thinks that the trouble began with his sister Maria, who took the veil, died young and remained in Auguste's heart as a lost ideal, even when he fell for his fellow sculptor, Camille Claudel: 'was Rodin's obsessive love, whipped to a peak of unobtainability in the summer of 1886, driving him to project onto her memories of his other stern task-mistress, Maria, the most unobtainable woman of all?' To which the short answer is: no. Butler is better on models than on lovers, as Rodin was himself. They would loll and stroll around his studio in the buff, to be caught on the wing, although it would be wrong to see Rodin as one of Picasso's randy satyrs; he lacked such devouring energy, and the drawings that emerged - languid sketches in pencil and wash - were as refined as they were candid. Artist and model, according to Rodin, 'work together as a productive force'. One up to the nekkid broads.

Ruth Butler pays tribute to Rodin: Sa Vie glorieuse, sa vie inconnue (1936) by his friend Judith Cladel, while looking askance at its 'heavy drama'. Well, better a dose of heavy drama than none at all. What niggles about Butler's achievement is that it seems so out of tune with her subject; she has acute points to make about the sculpture, but rarely gives herself a chance - most of the book is a welter of letters and committees and secondary detail. I was quite interested to learn that Rodin's friend Loie Fuller had a patron called Alma de Bretteville Spreckles, but it didn't really make my day. Too much of this merely blurs our view of Rodin, whereas Cladel gave it a direct intensity: she may have been too close to him for comfort, but there's nothing wrong with a little discomfort. What else can we expect as we bump into Rodin's life and the hard, unpretty shapes of his art, where lust and dejection burst out of blocks? What did he create, day after day, if not heavy drama?

Look at his Orpheus, leading Eurydice out of the stone shadows; he shields his eyes, of course, not wanting to turn round; but the gesture could also be a fit of weeping, as if Orpheus already knows the outcome of his adventure, and is lamenting the weakness that will bring it about. It was not just a question of telling a story - Rodin called The Burghers of Calais 'my novel' - but of telling it in different ways; hence, perhaps, his fondness for mythical subjects, the only kind that could match his medium for density. Within his grasp, the bride of quietness never stayed unravish'd for long; his work continues to move us because it appears to move and strain under our eyes, as if that weathered surface were no more than tough skin. Marble often feels too smooth and seemly for his needs; Rodin was more a man for the knotted tensions of bronze, for plaster and even terracotta, roughened and ready for the violent imprint of pain. It is impossible to calculate how much of that pain was his own - most of it, according to Ruth Butler, although the miracle is that it feels like everyone's. His first masterpiece, The Vanquished One, was renamed The Age of Bronze: suffering or hopeful heroism, take your pick. The struggle between them was the story of Rodin's life, and it will doubtless continue to tempt, and vanquish, his biographers.

(Photograph omitted)