Abstract

In this paper, I argue for two principles to determine the temporal interpretation of modal sentences in English, given a theory in which modals are interpreted against double conversational backgrounds and an ontology in which possible worlds branch towards the future, The Disparity Principle requires that a modal sentence makes distinctions between worlds in the modal base. The Non- disparity Principle requires that a modal sentence does not make distinctions on the basis of facts settled at speech time. Selection of the modal base will set these principles against each other, or allow for their cooperative interaction. For a root modal base, there is a conflict and disparity wins. The resulting interpretation is future. For a non-root modal base, the principles cooperate. Non-disparity determines a non-future interpretation and disparity requires the sentence to go beyond what is known by the speaker