Not long ago I had a telephone call from a somewhat distressed biography-writing friend. It had been his ambition to write a book about, well, let us call him X, a justly celebrated editor, poet and long-term ornament of the postwar literary scene who died some years ago. My friend’s difficulty lay not in finding a sponsor, for an enthusiastic publisher stood ready to sign him up, but in getting past Mrs X, his subject’s widow, who had expressed her opposition to the project. Was there anything he could do, he wondered? The straight answer, alas, was no, for Mrs X controlled her late husband’s copyrights. Without her say-so there would be no permission to quote and we would be in Eliot country, that debatable and problematic land in which Peter Ackroyd somehow managed to write his 1984 biography T S Eliot.