Hans Kamp

Does context and context-dependence belong to the research agenda of semantics - and, specifically, of formal semantics? Not so long ago many linguists and philosophers would probably have given a negative answer to the question. However, recent developments in formal semantics have indicated that analyzing natural language semantics without a thorough accommodation of context-dependence is next to impossible. The classification of the ways in which context and context-dependence enter semantic analysis, though, is still a matter of much controversy and some of these disputes are ventilated in the present collection. This book is not only a collection of papers addressing context-dependence and methods for dealing with it: it also records comments to the papers and the authors' replies to the comments. In this way, the contributions themselves are contextually dependent. In view of the fact that the contributors to the volume are such key figures in contemporary formal semantics as Hans Kamp, Barbara Partee, Reinhard Muskens, Nicholas Asher, Manfred Krifka, Jaroslav Peregrin and many others, the book represents a quite unique inquiry into the current activities on the semantics side of the semantics/pragmatics boundary.

This paper presents a sound and complete proof system for the first order fragment of Discourse Representation Theory. Since the inferences that human language users draw from the verbal input they receive for the most transcend the capacities of such a system, it can be no more than a basis on which more powerful systems, which are capable of producing those inferences, may then be built. Nevertheless, even within the general setting of first order logic the structure of the formulas of DRS-languages, i.e. of the Discourse Representation Structures suggest for the components of such a system inference rules that differ somewhat from those usually found in proof systems for the first order predicate calculus and which are, we believe, more in keeping with inference patterns that are actually employed in common sense reasoning.This is why we have decided to publish the present exercise, in spite of the fact that it is not one for which a great deal of originality could be claimed. In fact, it could be argued that the problem addressed in this paper was solved when Gödel first established the completeness of the system of Principia Mathematica for first order logic. For the DRS-languages we consider here are straightforwardly intertranslatable with standard formulations of the predicate calculus; in fact the translations are so straightforward that any sound and complete proof system for first order logic can be used as a sound and complete proof system for DRSs: simply translate the DRSs into formulas of predicate logic and then proceed as usual. As a matter of fact, this is how one has chosen to proceed in some implementations of DRT, which involve inferencing as well as semantic representation; an example is the Lex system developed jointly by IBM and the University of Tübingen )