For a stark illustration of the difference between entailment and quantifier accounts, consider a theory T that contains the single sentence ‘∃x K(x)’ and the theory T* that contains the single sentence ‘True(T)’ (see Peacock (2011: 81–2), who calls T* a “meta-theory”). T and T* mutually entail one another (assuming ‘K’ is not a semantical predicate); they thus have the same ontological commitments on an entailment account. And this seems right.  Surely, a philosopher cannot eliminate her commitment to Ks by switching from T to T*; it matters not that T*'s commitment to Ks is only implicit. But this implicit ontological commitment is invisible to the quantifier account because T* has no quantificational structure. Once again, by missing implicit commitments, the quantifier account fails to capture the ontological costs of a theory.