The focus of this thesis is a certain family of ontological positions. These positions say that there is some class of objects and properties, to which both physical objects and properties reduce and which are the kinds of things we confront in perceptual experience. Though largely absent from contemporary discussions of ontology, there are various reasons to think they deserve consideration. Species of this family, and similar views, have a prominent role in early analytic philosophy. Though endorsement of these views has been systematically de-emphasized in historical work on the period, Ernst Mach, William James, and Bertrand Russell are among philosophers who endorse such views in their work. Their views were motivated by a number of different considerations.

Here, I set to the side the issue of what has motivated these views in the past. I bring them up only for the purpose of giving attribution. I make no claim to ontological novelty nor will I be giving them an all-out defense. Accordingly, many considerations relevant to choice of ontology are bracketed. Instead of an all-out defense, what I offer here is an explanation of how adopting such a view allows us to solve two related problems. This amounts to two related reasons for taking a view like this seriously. One is for those who think that intuitions of a certain sort are a guide to what we should believe is ontologically the case. The other is for those who find merit in a disjunctive theory of perception.