Which part of Robert Irwin’s new book would you choose for the opening scene of a film of Ibn Khaldun’s life? Would it be the description of bodies, including those of Ibn Khaldun’s own parents, struck down by the Black Death in 14th-century Tunisia, or of the storm at sea that took the lives of his wife and five daughters? Would it be the story of our hero first bribing and then leading into battle nomadic tribesmen, forced in one campaign even to eat his own horse, or should the film open inside one of the many prison cells in which he awaited a change of regime? Would it be more fitting to start with a view of the writer in his eyrie above the cave-dwellers of western Algeria during the four years he retreated from the world to prepare his great study of human history? Or should the film flash back to the night when he was lowered down the walls of Damascus to enter the camp of Timur and parlay over peace and philosophy? And who would you want to play him? Sean Connery? Alec Guinness? Omar Sharif? Perhaps no one could capture every aspect of his personality.

In what he rightly calls an intellectual biography, the Arabic scholar and novelist Robert Irwin traces the ideas, more than the activities, of Ibn Khaldun. Perhaps best known in this country through the writings of 20th-century historians such as Arnold Toynbee and Hugh Trevor-Roper, who saw in him a