The Butlerian Jihad is a distant historical event within Dune’s fictional world that led to bans on thinking machines and the training of human calculation and judgment. Public encyclopedias and commentary distinguish the background presented in fragments in Frank Herbert’s early works from the machine war elaborated in later prequels. The originals question not just machines but also people who delegate judgment and the associated power relations. The cited fan wiki was blocked, so context was checked through other public sources. This is not AI-safety research or a new real-world event.