Foundation is a science fiction series written by Isaac Asimov. It is set in a future where a mathematician named Hari Seldon predicts the fall of the Galactic Empire and establishes a foundation to preserve knowledge and guide humanity through the dark ages that follow. The series spans thousands of years and explores the rise and fall of civilizations, as well as the concept of psychohistory, a fictional science that predicts the behavior of large groups of people. Foundation is highly regarded for its intricate world-building and thought-provoking ideas.