The biggest surprise in Patrick French's colourful biography of Sir Vidia Naipaul is that its biographee should have allowed it to be published. For it exposes him as an egotist, a domestic tyrant and a sadist to a degree that would be farcical if it were not for the consequent distress suffered over many years by his first wife, Pat. The book is, in large part, Pat's tragedy. They met at Oxford, and their early letters are touchingly innocent, frank and hopeful. She defied her family in marrying him, but things soon started to go wrong. It was partly, it seems, that he was too fastidious to commit himself wholly to another person. He would not give her a wedding ring, though she pleaded for one and eventually bought one herself. But it was also that she did not attract him sexually. He felt sexual desire to be shameful, and could not associate it with love. They were both too embarrassed to discuss his problem, and he began to consort with prostitutes, while Pat saw her hopes of motherhood fade.

Then, in 1972, he met an Anglo-Argentinian woman, Margaret Murray, and felt an instant attraction. They soon found that what French calls the kinks in their personalities matched. She enjoyed being his slave and victim, while he was aroused by mistreating and dominating her. It gave him, he said, carnal pleasure for the first time in his life. Being ignorant and not very bright (he estimated that her vocabulary was limited to 50 words), she was of no interest to him except as a sex object. When they were apart he did not bother to read, or even open, her letters. But, for the next 20 years, they would meet in locations around the world to do things that, Murray said, it would have made her sick to do with anyone else, though she longed to do them again with him. She cherished the wounds he inflicted as signs of his passion. On one occasion he beat her, on and off, for two days, until his hand became painfully swollen and her face was too disfigured for her to appear in public.

She left her husband and three children, in hopes that he would marry her. But he still needed Pat to guide, support and mother him, so he shuttled between the two women, repeatedly threatening each that he would put an end to their relationship. It destroyed Pat. The effect of his “hating and abusing” her, her diaries record, was to convince her of her own “revoltingness and folly”. He would reduce her to tears in front of guests, yet demand to be cosseted like a child. When he told her of his affair, he expected her to comfort him for being apart from Murray, and she did. Her love and admiration seem to have been limitless. In her diaries she refers to him as “the Genius”.

Murray became pregnant three times during their relationship. On the first occasion, Naipaul sent a cheque to cover the termination. “I was quite happy for it to be aborted,” he explains. “I would have had to give up so much.” The other two times he paid no heed, and left her to arrange what she called her “little murders” herself. This was typical of his undeviating self-concern, which French traces to the humiliations of his early life. Descended from destitute Indian labourers sent to Trinidad to cut sugar cane, he was made to feel inferior even within his own extended family by the failures and mental breakdowns of his beloved father, whom he was to commemorate in A House for Mr Biswas. By dint of heroic swotting, he won a scholarship and escaped to Oxford. But beneath its affability, 1950s Oxford was a maze of invisible barriers that he felt, rightly, had been erected to stop people like him succeeding. He tried to gas himself, but the coin-in-the-slot meter gave out while he was still conscious. Post-Oxford London was even worse. Nobody wanted to employ small, asthmatic Indians. He applied for and failed to get 26 jobs, and came close to starvation, living on boiled potatoes and handouts from Pat, who was working as a schoolteacher.

To survive these setbacks, as French sees it, he had to cling to a belief in his inherent superiority. In Trinidad, his maternal grandmother, the family matriarch, had insisted that they were Brahmins, and whether this was true or not, pride in caste became, for Naipaul, a vital distinction, requiring him to be served special food and granted special privileges. Even straightening the duvet on his bed was beneath his Brahminical dignity. His “malign jokes” about Negroes can also be traced, French suggests, to his childhood in Trinidad, where the Negro majority was felt by the Indians to be a threat, and where such joking was traditional. It even had a special name, picong. Which does not, of course, redeem it from being malign.

French's character analysis is not flattering, but it does justice to its subject's complexity. For Indians, too, fell far below Naipaul's standards. Highly sensitive to dirt, he complained that they defecated everywhere - on railway lines, on beaches, in parks. His first two books about India gave great offence. Yet it was, it seems, a kind of self-hatred. Long before he went to India, while he was still a child in Trinidad, his whole family of aunts, uncles and cousins had moved to a well-kept country estate, and reduced it to desolation, uprooting orange and mango trees and clearing the land for Indian peasant agriculture. The indoor WC was dismantled, as unacceptable to Hindu ideas of cleanliness, and a latrine was dug in the woods. It gave him an understanding, he says, of the ease with which a civilisation can be destroyed, and this became the dominant theme in his writing.

French's book is a magnificent achievement. He has mastered the huge Naipaul archive at the University of Tulsa, and has interviewed countless Naipaul friends and former friends worldwide. He took on the task only on condition that no direction or restriction should be imposed by Naipaul, and throughout he keeps his estimate of the man properly separate from his estimate of the writer, which is very high. But the achievement is partly Naipaul's. For he did not have to agree to these conditions, or speak to French so openly. He has chosen to submit himself to the truth-telling and ruthless objectivity that have always characterised his own work. In this respect, approving the publication, and asking for no changes in the typescript, may be seen as an act of self-lacerating honesty. And an act of remorse. For he accepts that his affair with Murray “undid Pat's life”, and that his publicly airing the fact that he had once been a “great prostitute man” devastated her, and brought her cancer back after a period of remission - “It could be said that I had killed her.” In the last glimpse we have of him, he is leaning against his car, tears streaming down his face, while his second wife, Nadira, whom he met and asked to marry him while Pat was dying, scatters Pat's ashes in a little wood.

The World is What It Is: The Authorized Biography of VS Naipaul by Patrick French

Picador £20 pp556

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