 A possible object is simply a part of a maximal spatiotemporally related whole (Lewis 1986). (Strictly speaking Lewis prefers to say “analogically spatiotemporal” instead of “spatiotemporal” but we shall let that pass.) By most criteria, Lewis’s possible worlds, hence also his possible objects, fall under the label ‘concrete’ rather than ‘abstract’. Every non-actual possible object (apart from pure Cartesian egos, perhaps) is a spatiotemporal object and bears no spatiotemporal relation to any actual object, or to any possible object exiting at any possible world at which it does not exist. This makes non-actual possible objects as real as non-actual possible worlds. It is worth while to remind ourselves that this does not make it automatically true to say that non-actual possible objects exist, even if we accept non-actual possible worlds. Whether it is true to say so depends on the domain of discourse with respect to which the existence predicate is to be understood.