John Norman, the pseudonym for John Frederick Lange Jr., is an American author and philosophy professor best known for his controversial Gor series of novels. Beginning with 'Tarnsman of Gor' in 1966, the series blends science fantasy with philosophical explorations, often drawing from his academic background. The books are set on the counter-Earth of Gor and are famous for their detailed world-building and depiction of a society with institutionalized female slavery. Despite facing significant criticism for its themes, the Gor series has cultivated a dedicated cult following and spurred discussions on freedom, power, and societal structures.