On Certainty is Wittgenstein's third masterpiece, and arguably the greatest contribution to epistemology since Kant's Critique of Pure Reason. The major aim of this collection - the first devoted exclusively to On Certainty - is to introduce philosophers and advanced philosophy students to a variety of significant contemporary attemtps to understand this brilliant but cryptic and under-appreciated final work. The essays have been grouped under four headings: the Framework, Transcendental, Epistemic, and Therapeutic readings, and an introductory preview helps explain why these readings need not be seen as antagonistic. The authors in this volume include leading Wittgenstein specialists, as well as philosophers known for their work in contemporary epistemology. The papers contribute not only to Wittgenstein scholarship but also to current issues in epistemology, philosophy of mind, philosophy of religion, ethics, philosophy of education, and philosophical methodology. This collection of essays will prove of invaluable assistance to scholars and students of Wittgenstein who have thus far only fleetingly ventured beyond Philosophical Investigations.Because of the enigmatic nature of On Certainty, this collection will be an essential tool in the comprehension of that work, and of Wittgenstein's legacy.