Traditional ontologies of tropes have proposed that tropes should be construed as ‘simple entities’ that have at once a qualitative and a particular character. These tropes form resemblance classes that can fulfill the functions of universals. The resemblance relation is an internal relation grounded on the intrinsic character of tropes. Douglas Ehring has argued that tropes cannot be simple. If they were, there could be different internal relations between the same tropes, which is at odds with their simplicity. Several objections have been presented against Ehring’s argument. It will be shown in this work that those objections can be answered. Ehring’s argument is strengthened with a groundtheoretic formulation which clarifies tha...