This article examines the role of scepticism in the Islamic philosophical tradition. It begins with a treatment of the origins and purpose of these discussions in classical kalām (c. 800–1100 CE). Then it moves on to the more mature discussions treating five forms of scepticism in the post‐classical period (c.1200–1800 CE), with the aim of demonstrating how they construed scepticism, the arguments for and against it, and what purposes scepticism played in their system. Three of these types of scepticism are (...) unrestricted, meaning that their denial of knowledge is universal. The other two types are restricted to a denial of inferential knowledge, either entirely, or in certain subjects such as metaphysics and natural philosophy. The discussion will focus on two of the most widely studied works of kalām: Saʿd al‐Din al‐Taftāzānī's Sharḥ al‐ʿAqāʾid al‐Nasafiyya and Jalāl al‐Dīn al‐Dawānī's Sharḥ al‐ʿAqāʾid al‐ʿAḍudiyya, including some of their super‐commentaries. (shrink)