The thesis presents a development of J. L. Austin's analysis of truth and its accompanying analysis of sentence structure. This involves a discussion and refinement of Austin's notions of the demonstrative and descriptive conventions of language and of the demonstrative and descriptive devices of sentences. The main point of the thesis is that ordinary language must be treated as an historical phenomenon: one that has evolved its more complex features through a long series of variations upon a small number of (...) rudimentary conventions and locutions. The utility of Austin's analysis is shown to lie in the description that it provides of the functions of these rudimentary conventions and locutions. The analysis is used to illuminate a number of problematic sentences and expressions of ordinary language, including identity sentences, definite descriptions, existential sentences, and conditionals. (shrink)