 Robb (1997) and Ehring (1996) offer token identity accounts on which features of things are “tropes” (particularized properties, such as the alleged particular whiteness of a given sheet of paper) and properties per se are sets or collections of tropes (see  entry on tropes).  We may suppose that every higher-level trope is identical with a lower-level physical trope, notwithstanding that the one trope is a member (or part) of different property-identifying sets of tropes, and hence of different types. Here again, the suggestion is that such a view avoids overdetermination while preserving a role for the distinctive efficacy/causal relevance of higher-level features.