Metaphysics, as the central discipline of philosophy, deals with fundamental questions about being, the essence of things in the world, and their relations to one another. Its insights form the foundation for numerous other disciplines, not only philosophical ones. The handbook covers all areas of metaphysics, starting from the question of what exists, including the problem of existence, space and time, philosophy of science, logic and semantics, and extending to the question of the status of metaphysics itself. It also provides a detailed overview of the history and methods of metaphysical thinking.