In recent years there has been an increasing use of logical methods and significant new developments have been spawned in several areas of computer science, ranging from artificial intelligence and software engineering to agent-based systems and the semantic web. In the investigation and application of logical methods there is a tension between: * the need for a representational language strong enough to express domain knowledge of a particular application, and the need for a logical formalism general enough to unify several reasoning facilities relevant to the application, on the one hand,...

This is a new edition of Gardenfors' classic text, presented to the community with a Foreword by David Makinson and an appendix containing a paper "Relations between the logic of theory change and nonmonotonic logic" by the author and David Makinson. The following describes the first edition: Knowledge in Flux presents a theory of rational changes of belief, focusing on revisions that occur when the agent receives new information that is inconsistent with the present epistemic state. It brings together, systematises and enlarges upon an already influential body of work by the author and his...