One day Sophie comes home from school to find two questions in her mailbox: Who are you? And where does the world come from? This is the start of Sophie’s adventure in philosophy from the Greeks to Descartes, from Spinoza to Hegel, Marx, and Freud with a mysterious mentor who will not reveal his identity. But this is not the only mystery in Sophie’s World. Why does she keep receiving postcards from someone called Hilde? Why do Hilde’s possessions turn up among her own? Who is Hilde and who, for that matter is Sophie herself? To solve the riddle. Sophie uses her new knowledge of philosophy, but the truth is far stronger than she could have imagined.