 On Lewis’s modal counterpart theory, every possible object is confined to one possible world. Indeed, Lewis defines a possible object as an object all of whose parts exist at some single possible world (Lewis 1986: 211). This conception of a possible object forces Lewis to resort to his counterpart theoretic account of modality de re (Lewis 1968). According to any possible-worlds theory of modality, to say that you could have been the leader of a religious cult is to say that at some possible world you are the leader of a religious cult. According to Lewis, to say that at a possible world you are the leader of a religious cult is to say that at that possible world there is a counterpart of you, that is, someone who resembles you to sufficient degrees in relevant respects, who is the leader of a religious cult. The counterpart relation is a similarity relation in most cases (but arguably not in all cases). As such, it is not an equivalence relation. This affords Lewis ample theoretical maneuverability but at the same time causes him some theoretical trouble. For example, as Lewis himself admits, his counterpart theoretic account of modality either yields the consequence that every actual object necessarily exists or yields the consequence that some actual object is not identical to itself (Lewis 1983: 32). There is also a famous complaint voiced by Saul Kripke (Kripke 1972: 344–45, note 13). It in effect says that whether someone other than you is the leader of a religious cult at some possible world is irrelevant to whether you could have been the leader of a religious cult. Lewis’s reply to this is that the de re character of the possibility is preserved by the stipulation that the person who is the cult leader is the counterpart of you, rather than the counterpart of someone else, at an appropriate possible world. For an attempt to avoid counterparts and still retain a broadly Lewisian realistic framework, see McDaniel 2004.