Cases of past absence involve agents noticing in retrospect that an object or property was absent, such as when one notices later that a colleague was not at a talk. In Sanskrit philosophy, such cases are introduced by Kumārila as counterexamples to the claim that knowledge of absence is perceptual, but further take on a life of their own as a topic of inquiry among Kumārila’s commentators and their Nyāya interlocutors. In this essay, I examine the Nyāya philosopher Gaṅgeśa’s epistemology of past absence, according to which agents learn that a recollectable object or property was absent by inferring its past absence from failing to recall that object or property. Gaṅgeśa’s account is best appreciated against the backdrop of earlier theories...