Трудно быть богом

The novel follows Anton, an undercover operative from the future planet Earth, in his mission on an alien planet, populated by human beings, whose society has not advanced beyond the Middle Ages. The novel's core idea is that human progress throughout the centuries is often cruel and bloody, and that religion and blind faith can be effective tools of oppression, working to destroy the emerging scientific disciplines and enlightenment. The book pays a lot of attention to the internal world of the main character, showing his own evolution from an emotionally uninvolved 'observer' to the person who rejects the blind belief in theory when confronted with the cruelty of real events.