This dissertation interprets Leibniz’ notion of perception through abilities, agency, and action. In chapter 1, I characterize the differences between kinds of Leibnizian perception by considering their relationship to different abilities. I focus on lower cognition, where Leibniz distinguishes bare perception from sensation by their degrees of distinctness and memory. I read this relationship, between kinds of perception and qualities of perception, through actions. I begin with complete lacks of distinctness and memory and how they relate to stupors as an (...) inability to act. I then turn to a range of incrementally more advanced cases of perceptions and actions to highlight the role of distinctness and memory in each. The cases reveal how differences in kinds of action depend on differences in kinds of perception in Leibniz’ system. My approach breaks with traditional readings that invoke consciousness to account for the differences, and it builds in some ways on readings that lead with representation. I also comment on the prospects of such an abilities based approach for 21st century theories of perception. In chapter 2, I articulate the point of view or perspectival nature of Leibnizian perception through expression and agency. I establish some conditions that Leibniz sets on perspectival expression for individual perceivers, and on the particular way that perceptions belong to their perceivers in Leibniz’ system. I argue that spatial, geometrical notions of perspective, though useful, ultimately give way to a deeper, agential notion of perspective for Leibniz. I make a case for including an agential side of POV in perception, beyond the phenomenal flow of perception. I then articulate how agency is unique and fundamental to Leibniz’ notion of perspective or point of view, both in internal action and in the activity and passivity of external action. In chapter 3, I ask about the limits of perceivers in Leibniz’ system—where they arise and where they don’t. I set the question adjacent to Leibniz' celebrated mill argument. I consider readings of the argument that invoke action, and build on them to include questions about how action relates to interaction in different kinds of perceivers. One question concerns the lack of perception in primary matter, and another concerns the lack of perception in an aggregate of secondary matter. After milling through some considerations, I settle on a notion of organic unity, underpinned by a notion of action, that can draw lines between Leibnizian perceivers and non-perceivers. (shrink)

We present a logic which we call Hybrid Duration Calculus. HDC is obtained by adding the following hybrid logical machinery to the Restricted Duration Calculus : nominals, satisfaction operators, down-arrow binder, and the global modality. RDC is known to be decidable, and in this paper we show that decidability is retained when adding the hybrid logical machinery. Decidability of HDC is shown by reducing the satisfiability problem to satisfiability of Monadic Second-Order Theory of Order. We illustrate the increased expressive power (...) obtained in hybridizing RDC by showing that HDC, in contrast to RDC, can express all of the 13 possible relations between intervals. (shrink)