Philip José Farmer (January 26, 1918 – February 25, 2009) was an American author, principally known for his award-winning science fiction and fantasy novels and short stories.Farmer is best known for his sequences of novels, especially the World of Tiers (1965–93) and Riverworld (1971–83) series. He is noted for the pioneering use of sexual and religious themes in his work, his fascination for, and reworking of, the lore of celebrated pulp heroes, and occasional tongue-in-cheek pseudonymous works written as if by fictional characters. Literary critic Leslie Fiedler compared Farmer to Ray Bradbury as both being "provincial American eccentrics" who "strain at the classic limits of the [science fiction] form," but found Farmer distinctive in that he "manages to be at once naive and sophisticated in his odd blending of theology, pornography, and adventure.