A correct analysis of ontological commitment, however theoretically valuable, might do nothing towards providing an adequate test. Such an analysis, unaccompanied by a test, would be of little help in determining the ontological costs of theories, or resolving ontological disputes. Entailment accounts have good claim to providing a correct analysis of ontological commitment; but they do not provide a test. For one thing, the parties to an ontological dispute will often disagree as to what propositions are expressed by the sentences of a theory, that is, as to what the truth conditions of those sentences are. Quine's criterion bypasses this problematic step by applying the criterion only to already regimented theories. For a second thing, parties to an ontological dispute will often disagree over the existential entailments of a theory (see §2.2 below).  Quine's criterion (as he understood it) avoids this problem by focusing on the formal relation of logical entailment between sentences, a relation that is well understood. The material relations of entailment between the propositions, however—be they modal, or conceptual, or a priori—are matters of much dispute. If the goal is to find an adequate test for ontological commitment, entailment accounts fall short.