 The question remains of how to understand quantification into sentence position. One may in fact be tempted to assimilate propositional quantification to either singular quantification over propositions or to substitutional quantification over a range of sentences. While Prior (1971) and Grover (1972), for example, take propositional quantification to be importantly different from singular and substitutional quantification, Richard (1996) suggests that propositional quantification should at the end of the day be treated as a species of singular quantification, e.g., singular quantification over propositions. Indeed, one may be tempted by this option by reflecting on what we did above. We expanded the language of propositional modal logic with a new style of quantification, but the model theory explained the truth conditions associated with the propositional quantifier, \(\forall p A\), in terms of singular quantification over sets of worlds in the model.