Towards a framework for semantic information

Abstract

This thesis addresses some important questions regarding an account of semantic information. Starting with the contention that semantic information is to be understood as truthful meaningful data, several key elements for an account of semantic information are developed. After an introductory overview of information, the thesis is developed over four chapters. 'Quantifying Semantic Information' looks at the quantification of semantic information as represented in terms of propositional logic. The main objective is to investigate how traditional inverse probabilistic approaches to quantifying semantic information can be replaced with approaches based on the notion of truthlikeness. In 'Agent-Relative Informativeness' the results of the previous chapter are combined with belief revision in order to construct a formal framework in which to, amongst other things, measure agent-relative informativeness; how informative some piece of information is relative to a given agent. 'Environmental Information and Information Flow' analyses several existing accounts of environmental information and information flow before using this investigation to develop a better account of and explicate these notions. Finally, 'Information and Knowledge' contributes towards the case for an informational epistemology, based on Fred Dretske's information-theoretic account of knowledge.