An American author and self-described "scientific humanist," he is best known for The Godhead Trilogy. His other works include The Last Witchfinder and The Philosopher's Apprentice.
He studied at Harvard University and the University of Pennsylvania.
He was a three-time recipient of the Nebula Award.
With his wife, Kathryn Smith Morrow, he had one son.
His novel, Blameless in Abaddon, features a lawyer character who represents a parodied version of author C.S. Lewis.