 He claims that the problem of coincident entities arises not due to the diversity of individuals in a region, but rather due to the fact that the world as it is under-determines which principles of individuation are the correct ones to employ. We can treat any property as accidental or as essential by employing different sortals, or nominal essences, to describe a thing. When a cow dies, we can describe this either as the accidental change in some flesh-and-bones, or the substantial change in a cow which is no more. Sidelle concludes, in a Lockean vein, that which changes we conceive of as substantial and which as accidental is more a function of us and our interests than of the way things really are (1998, p. 439).