Sophie's World

A 1991 philosophical novel by Norwegian writer Jostein Gaarder, combining elements of fiction and a philosophy textbook. The main character, fourteen-year-old Sophie Amundsen, lives in Norway and begins receiving mysterious letters with questions like "Who are you?" and "Where did the world come from?" These messages lead her to a secretive philosophy teacher, Alberto Knox, who guides her through the history of Western thought—from ancient philosophers to 20th-century existentialists. However, Sophie gradually realizes that she herself is part of a complex intellectual experiment. The novel not only provides an engaging introduction to philosophy but also explores themes of reality, consciousness, and free will.