One of Lewis' more complex works, The Great Divorce sometimes gets included with both his fiction and his non-fiction. It is not a novel, but it is more like a long parable or just an extended metaphor. Hell has an open door and everyone is free to leave whenever they want, but the pride, skepticism, nihilism, and other psychological hangups of the damned prevent them from accepting God's grace. Lewis' ideas were not as orthodoxy as everyone assumes. Here and in The Last Battle he hints at a form of universalism in which the only thing that prevents everyone from entering heaven is personal stubbornness.