In this paper, we discern different types of possible relations. We focus on the distinction between internal and external relations and their various possible sub-types. In the first section, we present what is nowadays more or less the standard distinction between internal and external relations. In the second section, we make two contributions to the literature of internal relations: a new taxonomy of internal relations and a novel distinction between formal and material ontological relations. In the third section, we discuss (...) three distinctions among external relations, in particular the distinction between relata-specific and relata-unspecific relations. We argue that relata-specific external relations are a promising but incomplete solution to the vexed problem of Bradley’s relation regress. (shrink)

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. (shrink)