Propositions and centered content

Abstract

This thesis investigates the nature of propositions. It examines three central theoretical roles of propositions: the role of semantic values, objects of attitudes, and contents of assertion. Chapter 2 and 3 study the nature of propositions in their role as compositional semantic values of sentences, while Chapter 4 and 5 explore their role as objects of attitudes and contents of assertion. Chapter 2 aims to show that semantic values of sentences cannot be identified with eternal propositions and gives a partial defense of Temporalism about semantic values. Chapter 3 defends a Fregean conception of semantic values. Chapter 4 presents a model of communication on which the truth of propositions in their roles as contents of attitudes and assertions is world, time and subject relative. Chapter 5 argues against Stalnaker's rival attempt of identifying both attitudinal and assertoric contents with eternal and impersonal propositions.