Situation theory has been developed over the last decade and various versions of the theory have been applied to a number of linguistic issues. However, not much work has been Clone in regard to its computational aspects. In this paper, we review the existing approaches towards 'computational situation theory' with considerable emphasis on our own research.
IntroductionSituation theory is an attempt to develop a mathematical theory of meaning which will clarify and resolve some tough problems in the study of language, information, logic, philosophy, and the mind [11]. It was first formulated in detail by Jon Barwise and John Perry in 1983 [12] and has matured over the last decade [25]. Various versions of the theory have been applied to a number of linguistic issues, resulting in what is commonly known as situation semantics [7,8,10,24,31,33,35,58]. The latter aims at the construction of a unified and mathematically rigorous theory of meaning, and the application of such a theory to natural languages.Mathematical and logical issues that arise within situation theory and situation semantics have been explored in numerous works [8,10,12,24,25,33]. In the past, the development of a mathematicM situation theory has been held back by a lack of availability of appropriate technical tools. But by now, the theory has assembled its mathematical foundations based on intuitions basicaLly coming from set theory and logic [1,8,24,26]. With a remarkably original view of information (which is fully adapted by situation theory) [28,29], a 'logic,' based not on truth but on information, is being developed [25]. This logic 1 will probably be an extension of first-order logic [5] rather than being an alternative to it.Individuals, properties, relations, spatio-temporal locations, and situations are basic constructs of situation theory. The world is viewed as a collection of objects, sets of objects, properties, and relations. Infons ('unit' facts) [26] are discrete items of information and situations are first-class objects which describe parts of the real world. Information flow is made possible by a network of abstract 'links' between high-order uniformities, viz. situation types. One of the distinguishing characteristics of situation theory vis-£-vis another influential semantic and logical tradition [27] is that 1 According to The Advanced Learner's Dictionary of Current English (by A. S. Hornby, E. V. Gatenby, and H. Wakefield, London, U.K.: Oxford University Press, 1958), logic is the science or art of reasoning, proof, and clear thinking. Thus, the commonly accepted equation logic = first-order logic is highly suspect. (Cf. [6] for an extended argument on this.) information content is context-dependent (where a context is a situation).All these features may be cast in a rich formalism for a computational framework based on situation theory. Yet, there have been few attempts to investigate this [17,33,40,46,49,52,59]. Questions of what it means to do computation with situations and what aspects of the theory makes t...
