Abstract
This chapter discusses Peter John Olivi’s conception of the role of dispositions in sensory cognition from metaphysical and psychological perspectives. It shows that Olivi makes a distinction between two general types of disposition. Some of them account for the ease, or difficulty, with which different persons use their cognitive powers, while others explain why people react differently to things that they perceive or think. This distinction is then applied to Olivi’s analysis of three different psychological operations, where the notion of disposition figures prominently; estimative perception, perceptual clarity, and the perception of pain and pleasure. The chapter argues that Olivi uses cognitive dispositions in an interesting way to explain individual differences between persons, and that they reveal the dynamic nature of his conception of human psychology.