These embarrassing revelations are only interesting in that they dramatize the old question of the writer "as a writer" and the writer "as a person." Are these character flaws in some way linked to, explained or redeemed by, his writing? Most achievement requires a certain amount of self-absorption and ruthlessness, but Naipaul chose to nurture his talent over his humanity to a very dramatic degree indeed. Reading the book, I kept alternating between finding something monstruously admirable about his dedication to his writing (to himself) and thinking that ten Nobel Prizes couldn't make him less of a wretch.
Then there is the matter of Naipaul's writing. I am in awe of his adamantine prose, his eye for detail. Yet much of what he writes about the non-Western world is scathing--the obvious product of shame (Naipaul came from an Indian family that emigrated to Trinidad as indentured servants--he came to England on a scholarship), shame in which there is truth but also an unfair harshness. But Naipaul is not disingenuous in his writing--he does the hard work of expressing his thoughts with the outmost clarity and precision. Even when one disagrees with what he says, one has to do one's own hard work, articulating one's disagreement in the face of a very sharp, honed, persuasive voice--and this engagement is generally intellectually rewarding.
I haven't read that many Naipaul books (A Million Mutinies Now, his last and reportedly kindest book on India; the collection of essays A Way in the World; and the beginning of A House for Mr. Biswas--the book met an unfortunate accident before I could get too far). I have a good friend who picked up Among the Believers--Naipaul's book on Islam--and was so outraged that she never read another book by him again. It does seem that Naipaul set out to write his books about Islam (there was a follow-up, Beyond Belief) with the express purpose of criticizing it. He interpreted the Muslim invasions of India between the 11th and 17th century as devastating to Indian civilization. In general, his writing on Muslim and African countries seems animated by religious and racial bias.
French is happy to expose Naipaul's personal foibles, but he doesn't engage quite as critically with his writing. Like many in Naipaul's life, French deplores the man but admires the writer. (He wouldn't have written a biography of someone he didn't consider exceptional, after all). But while having strong positions and clear points of view was one the strengths of Naipaul's writing, sometimes he was wrong, and his writerly prowess should not be allowed to obscure that. French points out the absurdity of Naipaul's position that "Everyone not an Arab who is a Muslim is a convert," even if that conversion happened centuries ago--Naipaul saw all non-Arab Muslim countries as still the victims of Islamic "imperialism." But French quotes approvingly from Bernard Lewis' defenses of Naipaul, while saying that Edward Said (a constant critic) wrote "jealously" against him. And he justifies Naipaul's "admonitory pessimism" about political Islam by invoking 9/11 (!), turning Naipaul's bias into prescience.
French's biography is one of the best I've read, thoughtful and engrossing. Naipaul is a great writer and an often impressive observer and thinker. His harsh appraisal of post-colonial countries is uncomfortable in part because it contains so much truth. But his insights and his talents are compromised--at times, irredeemably so--by his prejudices.