The principal aim of this thesis is to assess the view that the formal properties of sentences of natural languages encode truth-conditions. The question I pursue is whether truth-conditional semantic theories are capable of accounting for the various ways in which contextual factors contribute to the determination of the truth-conditional content of sentences. The thesis will assess and evaluate three different approaches standard contemporary truth-conditional semanticists have set forth in response to what I shall refer to as the challenge from pervasive context sensitivity, which is essentially the claim that context plays a more extensive role in the determination of content than that of fixing the semantic values of standard indexical expressions. I shall aim to show that each of the approaches mentioned fails to provide an adequate account of how the phenomenon of context sensitivity can be explained on the basis of our linguistic competence alone, and shall then explore some of the consequences of this
