"Are you turning into neo-conservatives?" a friend asked after I and other leftish critics had hammered Russell Brand's new book, Revolution. With evident relish, he went on, you have laid into a celebrity who for all his garrulous follies is against plutocrats, media corporations and the degradation of the environment. You say you are left-wing, but like the original neo-cons or the type of "leftist" Rupert Murdoch is so fond of employing, you only ever offer comfort to the Right.

He asked a fair question to which the simple answer is that a bad book is a bad book whatever the politics of its author, and the honest reviewer must say so. Revolution (Century, £20) is an exceptionally bad book, one of the worst I have ever read. I doubt anyone who is not paid to review it can reach the end without skimming large sections, and many will throw it away. Brand is a raging narcissist, who treated as brilliant whatever thoughts entered his cloudy mind while he underwent a recovery programme from drink and drug addiction. His egomania is such he thinks he can transform the world because he transformed himself when he kicked heroin.

I've just opened my copy at random. The first line in front of me is: "When you get Richard Dawkins yapping menopausally at some poor hamstrung old archbishop, while we dismantle our environment due to the materialistic, pessimistic principles that the atheistic tyranny of the day is tacitly sponsoring, it is time to look for a new story" — a sentence which is simultaneously chaotic, untrue, and cowardly. (The only "atheistic tyrannies" are North Korea, China and Cuba. Brand means the United States and Britain, however, but lacks the nerve to make such a false statement openly.) Toss this book in the air, and let it fall where it may: you can perform similar dissections on every second sentence you find.

The wider reason for the disdain is that Brand is a creature of a malign culture, which is turning public debate into celebrity babble. When the New Statesman needs a circulation lift or the BBC needs a ratings boost, they turn to Brand. Because he is a star, not one of his friends or editors at Century told him that he couldn't write, and would not be able to write until he had mastered the skills of self-criticism and fact-checking. Stars expect and receive reverence, which is why it has taken so long for the legal system to prosecute celebrity rapists.