Will Self is not pleased with how things are going. Since the publication of his successful debut short-story collection, The Quantity Theory of Insanity (1991), much has changed in his life and in his outlook. There’s the dismal quality of fiction – Sally Rooney has been one victim of his bile – and the public feud between Self and his ex-wife, the late journalist Deborah Orr, who accused him of emotional cruelty. In the aftermath, he lost admirers and friends alike. Then the rare blood cancer, with which he had been living for almost a decade, intensified its scarring of his bone. At sixty-four, he can barely walk. So when Phil Szabo, a character in his latest novel, thinks to himself that ‘ours is a society in decline’, one is not surprised by the scope of this sweeping assessment and the strength of its pessimism. Self doesn’t know when this slide began. But in The Quantity Theory of Morality, which comes thirty-five years and thirteen novels after his debut collection, he seems confident about the underlying cause: a general decrease in what he terms ‘the morality quotient’. 

The book takes the form of a story cycle, offering a series of variants of the same set of events. Each tale starts at a Hampstead dinner party populated by snooty, middle-class friends. The soiree unfolds slightly differently in each rendition. In the first, the narrator informs the reader with