"After the Last War destroyed most of the world, survivors form a new society in four self-sustaining cities in the Mojave Desert. In the utopia of the Four Cities, inspired by the lyrics of 'Imagine' and Buddhist philosophy, everything is carefully planned and controlled: the seasons, the weather--and the residents. To prevent mankind from destroying each other again, its citizens undergo a memory wipe every four years in a process called tabula rasa, a blank slate, to remove learned prejudices. With each new cycle, they begin again with new names, jobs, homes, and lives. No memories. No attachments. No wars"--