 According to standard trope theory, two objects, a and b, ‘share’ a property—F-ness— if at least one of of the tropes that make up a belongs to the same (exact) resemblance class as does at least one of the tropes that make up b (cf. Williams 1997[1953]: 117–118; Campbell 1990: 31f.). The majority of the trope theorists agree that exact resemblance is to be formally characterized as an equivalence relation (although cf. Mormann 1995 for an alternative view), i.e., as a relation that is symmetrical, reflexive, and transitive. As such, exact resemblance partitions the set of tropes into mutually excluding and non-overlapping classes; classes functioning more or less as the traditional universal does.