Abstract
According to Lowe’s Four-Category Ontology, the general nature of the entities belonging to the four fundamental categories is determined by the basic formal ontological relations (instantiation and characterization) that they bear to other entities. I argue that, in closer analysis, instead of one formal relation of characterization, this category system introduces two, one connecting particulars and another universals. With regard to the characterization relation connecting particulars, it remains an open issue whether it would need further analysis. By contrast, the status of instantiation as an internal relation is comparatively clear. Nevertheless, because of holding by virtue of the essences of particulars, the holding of instantiation between universals and particulars rules out the possibility of kind change and entails that particulars are essentially rigidly dependent on universals. Finally, Lowe’s analysis of necessary exemplification gives us some reasons to suspect that some property universals need not have any instances in order to exist.