Michael John Harrison (born 26 July 1945), known for publication purposes primarily as M. John Harrison, is an English author and literary critic. His work includes the Viriconium sequence of novels and short stories (1971–1984), Climbers (1989), and the Kefahuchi Tract trilogy, which consists of Light (2002), Nova Swing (2006) and Empty Space (2012). He is widely considered one of the major stylists of modern fantasy and science fiction, and a "genre contrarian". The Times Literary Supplement described him as 'a singular stylist' and the Literary Review called him 'a witty and truly imaginative writer'. Robert Macfarlane has said: "Harrison is best known as one of the restless fathers of modern SF, but to my mind he is among the most brilliant novelists writing today, with regard to whom the question of genre is an irrelevance."