ABSTRACT
This chapter focuses on interesting aspect of intensional semantics, namely its interface with the topic of indexicals. In general, the reference of an indexical depends on the context of utterance. For each possible context of utterance, the rule specifies what the referent of an utterance of the indexical would be at that context. Tense represents indexicality with respect to time. The intension of ' is bat' determines the same extension as ' is a flying mammal' in the actual world, but determines a different extension at other possible worlds, such as one with flying dolphins. The truth-value of 'Barack Obama is the 44th US president' is the same as that of 'Voltaire wrote Candide'; but the equivalence is only an actual one; in other possible worlds the two have different truth-values. The context of utterance includes, in addition to the time and place of the utterance, the possible world in which the utterance takes place.
