Abstract: There are no statues or rocks or chairs. But there are microscopic objects arranged statuewise and rockwise and chairwise. Moreover, there are—in addition to microscopic objects arranged humanwise—composite human organisms.The ontology of Objects and Persons is motivated, in large part, by causal considerations. One of the central conclusions is that physical objects are causally non-redundant: physical objects cause things that are not wholly overdetermined by their parts. I ‘eliminate’ statues and other inanimate composite macrophysical objects on the grounds that they would—if they existed—be at best completely causally redundant.I defend our existence by arguing, from certain facts about mental causation, that we human beings cause things that are not already caused by our parts.A second strand of argument for the book's overall ontology involves a variety of philosophical puzzles, puzzles that are dealt with in illuminating and often novel ways. These puzzles support eliminativism regarding statues and rocks and chairs, but—I argue—do not support eliminating us human organisms.Many other issues are addressed along the way, including free will, the ‘reduction’ of a composite object to its parts, and the ways in which identity over time can ‘for practical purposes’ be a matter of convention.

Keywords: artifacts, composition, free will, human organisms, identity, mental causation, Trenton Merricks, metaphysics, objects, ontology, parts, personal identity, persons, philosophy of mind