Names are astonishingly important in Dune. Most characters carry multiple titles, nicknames, honorifics, or alternative identities. Paul Atreides walks a long, complicated journey exemplified in part by his new names. He is Paul Atreides, next in line to become Duke of Caladan. Then he is Usul or Paul-Muad'Dib, the mighty Fremen freedom fighter. To the billions who take part in his holy war, he becomes Muad'Dib. Where did the most consequential name in the Dune universe come from?