The Prolegomena is often dismissed as Kant's failed attempt to popularize his philosophy, but as the essays collected here show, there is much to be gained from a careful study of the work. The essays explore the distinctive features of the Prolegomena, including Kant's discussion of philosophical methodology, his critical idealism, the nature of experience, his engagement with Hume, the nature of the self, the relation between geometry and physics, and what we cognize about God. Newly commissioned for this volume, the essays as a whole offer sophisticated and innovative interpretations of the Prolegomena, and cast Kant's critical philosophy in a new light.