Coincidence as Overlap 1

Material constitution and coincidence are widely discussed but poorly understood. This paper is an attempt to make progress by developing an account of how numerically distinct material objects coincide when one constitutes the other. I address two central issues: first, do material coincidents share their proper spatiotemporal parts, and if so, do they share all of them? Second, how can material coincidents share their spatiotemporal location and matter, so share material properties such as having mass m, shape s, and location 1, but not share all of their properties? To answer these questions, I develop a property mereology for objects and argue that coincidents overlap with respect to all of their spatiotemporal parts but not all of their property parts. If we can adequately explicate coincidence, we can begin to answer questions about material constitution and related questions about de re modality, persistence, supervenience, redundant causation, event individuation, personal identity, nonreductive materialism in mind, and reference.