In Doubts on Avicenna, Ayman Shihadeh brings to light an important new source, which marks a key moment of transition in twelfth-century Arabic philosophy. Sharaf al-Dīn al-Masʿūdī’s al-Mabāḥith wa-l-Shukūk ʿalā l-Ishārāt (Investigations and Objections on the Pointers) offers major insight into the dialectic between the two traditions of Avicennan philosophy and rational theology,…