One view of ontology has dominated Western philosophy since the Greeks: the most basic furnishings of the world are things or, in more technical philosophical terms, substances. These are thought of as integrated, persisting through time, not dependent on anything external for their existence, and as the bearers of properties. They are also the subjects of change. This chapter begins with the proposal that we should treat organisms not, as is traditional, as a kind of thing or substance, but as a kind of process. The author begins by explaining this idea a bit further and outlining some of the reasons in its favor. He then considers some of the implications for this position on how we should understand the classification of organisms. Finally the author shows how these considerations provide a deeper ground for the classificatory pluralism that he has advocated for many years.