ABSTRACT
In this chapter the author examines the predominant fundamental mereology on offer in the contemporary literature, Part-Priority, as expressed in its most popular guise, Priority Microphysicalism (PM). The chapter begins by unpacking a few of the core tenets of PM in particular and then considers some of the lines of reasoning that have been advanced in its favor. The author then set his sights on Part-Priority in general arguing that it is ill-suited to account for the metaphysical possibility of gunky worlds, worlds devoid of mereological simples. He then turns to considerations regarding the failure of whole-part supervenience within the domain of physics, chemistry, and biology with respect to both microphysical and macrophysical wholes, thereby taking aim at both Part-Priority and PM. The recent advent of systems biology illustrates a biological holism with respect to the proper parts of living organisms.
