Abstract

When is a proposition true? It is common to expert an answer of the form “at instant x”. In section I) I present an example of the consequences that such instantaneous semantics in tense logic can have, and review some of the problems that have led to the proposal of using intervals, rather than instants, as the indices at which to evaluate propositions. In the section II) I present some of the problems with the intervals themselves, and in section III) I consider the possibilities of having he best of both worlds. Due to the still tentative character of interval semantics, I focus on the consideration of metatheoretical issues rather than on the technical points of the particular systems of interval semantics so far proposed