Situations, unlike worlds, are not complete in the sense that every proposition or its negation holds in a world. According to Situations and Attitudes, meaning is a relation between a discourse situation, a connective situation and a described situation. The original theory of Situations and Attitudes soon ran into foundational difficulties. A reformulation based on Peter Aczel's non-well-founded set theory[2] was proposed by Barwise before this approach to the subject petered out in the early 1990s.
Barwise and Perry's system was a top-down approach which foundered on practical issues which were early identified by Angelika Kratzer and others. She subsequently developed a considerable body of theory bottom-up by addressing a variety of issues in the areas of context dependency in discourse and the syntax–semantics interface.[4] Because of its practical nature and ongoing development this body of work "with possible situations as parts of possible worlds, now has much more influence than Barwise and Perry’s ideas".[5]
