 Quine (1948) explicitly characterizes ontology as an attempt to answer the question “what is there?” As he observed, the question may seem deceptively simple, since it may be answered in a word: “everything”. The problem with this answer is that it is largely uninformative. All parties agree that everything is something, but there is still plenty of room of disagreement as to what kinds of objects are there. Are there mereologically composite objects? Are there concrete possible worlds? Are there mathematical objects? If there are such objects, then they will of course lie in the domain of the quantifier “everything”. However, philosophers are still intensely divided as to whether they do.