Description Grammar for Discourse Description Grammar for Discourse een wetenschappelijke proeve op het gebied van de Filosofie Proefschrift ter verkrijging van de graad van doctor aan de Radboud Universiteit Nijmegen op gezag van de Rector Magnificus prof. mr. S.C.J.J. Kortmann volgens besluit van het College van Decanen in het openbaar te verdedigen op woensdag 5 december 2007 om 10.30 uur precies door Nora van Leusen geboren op 15 oktober 1967 te Arnhem Promotores: Prof. dr. R.A. van der Sandt Prof. dr. ir. R.J.H. Scha (Universiteit van Amsterdam) Manuscriptcommissie: Prof. dr. M.V.P. Slors Prof. dr. N.M. Asher (University of Texas, Austin) Dr. C. Gardent (CNRS Director of research, LORIA/Nancy) c Noor van Leusen ISBN 978-90-9022305-6 Typeset with LATEX2ε Cover design by Marianne Stoop Printed by Gildeprint Drukkerijen, Enschede Voor Reinhard 3 Acknowledgements The research for this work started at the University of Amsterdam and, after interludes in Saarbr¨ucken and Stuttgart, resulted in a dissertation at the Radboud University in Nijmegen. As an effect of these travels, I am now blessed with two promotors, Rob van der Sandt and Remko Scha. I would like to thank Remko, the most friendly and patient person alive, for sharing his views on discourse semantics with me in most enjoyable conversations. To Rob I am deeply grateful for instigating me to take up my research again and finish the book. Thank you for many hours spent on discussing general issues in semantics and presupposition theory in particular, for being very clear about planning and time-constraints, for occasional trips to the Ooijpolder and to musical events, and for instructions on how to pickle salmon. You’ve been wonderful. I would also like to thank Henk Zeevat for inspiring discussions during my years in Amsterdam, and my colleagues there, in particular the one-time inhab- itants of room 337 of the PC Hoofthuis, for making me feel at home at Alfa- Informatica. During a later period at the ILLC, Paul Dekker has been extremely supportive and helpful. In recent years, I joined the small but sociable philosophy of language group in Nijmegen led by Rob van der Sandt. In addition to Rob, I would like to thank Bart Geurts, Emar Maier, Janneke Huitink, and Corien Bary for taking me up in their midst. I much enjoyed your company, and the weekly gossiping during ‘vakgroepslunch’. You’re a talented bunch of people and I hope you will all find your way in Academia as succesfully as you deserve. 5 Contents 1 Introduction 11 2 Logical Description Grammar 21 2.1 Introduction.............................. 21 2.2 TreeAdjoiningGrammar. 22 2.3 DescriptionGrammars . 26 2.4 LDGinDetail............................. 30 2.4.1 OverallWorkingoftheGrammar . 31 2.4.2 Parsing an Ambiguous Sentence: An Example . 33 2.4.3 GeneralDescriptions . 36 2.4.4 Positive and Negative Anchoring . 37 2.4.5 InputDescriptions . 40 2.4.6 LexicalDescriptions . 41 2.5 Conclusion............................... 44 3 LDG for Discourse Analysis 47 3.1 Introduction.............................. 47 3.2 A FrameworkofDiscourse Interpretation . 49 3.3 Sentence and Discourse Theory Integrated . 53 3.4 Discourse Structure and Discourse Relations . ... 55 3.5 IncrementalLDG ........................... 64 3.5.1 Circumscription of Lexical Nodes . 65 3.5.2 InputDescriptions . 66 3.5.3 TheIncrementationOperation+ . 68 3.5.4 Reasoning about Discourse Descriptions . 70 3.5.5 AttachmentattheRightFrontier . 77 3.5.6 Deterministic Discourse Processing . 81 3.6 SummaryandLooseEnds . .. 84 7 8 Contents 4 Discourse Semantics 89 4.1 Introduction.............................. 89 4.2 DiscourseMeaning .......................... 91 4.3 Nonmonotonic Discourse Contributions . 96 4.4 Context Sensitive Compositional Semantics . ... 98 4.4.1 Finegrained CDRT: Basic Concepts and Notation . 100 4.4.2 Decorating Tree Structures with Local Contexts . 103 4.4.3 Lexical Descriptions of some Basic Word Classes . 106 4.4.4 Discourse Relations, Connectives, and Adverbials . 110 4.4.5 Global Consistency and Informativity Conditions . 124 4.4.6 Inferring Semantics from Discourse Descriptions . 131 4.4.7 Testing Context Sensitive Constraints . 135 4.5 Conclusion............................... 143 5 Anaphoricity 147 5.1 Introduction.............................. 147 5.2 PropernessandPronounResolution . 149 5.2.1 Inferring Binding Relations . 150 5.2.2 Semantic Accessibility and Parallelism . 153 5.2.3 Kataphors........................... 155 5.2.4 Summingup.......................... 156 5.3 Syntactic Binding Principles in LDG . 157 5.4 Discourse Topic Structure and Salience . 160 5.5 AccommodatingBinders . 169 5.6 Conclusion............................... 172 6 Presupposition Theory 175 6.1 Introduction.............................. 175 6.2 Binding and Satisfaction in Tandem . 178 6.2.1 Presupposition Triggers in the Lexicon . 179 6.2.2 Reasoning about Presuppositional Conditions . 184 6.2.3 Binders can be Globally Accommodated . 187 6.2.4 Referential and Existential Readings of Definites . 190 6.2.5 Accommodating Weak and Strong Readings . 191 6.2.6 Partial Matching and Suitability . 193 6.2.7 Bridging............................ 194 6.3 Consistency and Informativity Revisited . 198 6.3.1 Global Consistency and Global Informativity . 198 6.3.2 Van der Sandt’s Acceptability Conditions . 202 6.3.3 Conclusion-WaystoGo. 208 6.4 GeneralisedAccommodation . 210 6.4.1 Some Examples of Nonpresupposing Discourse . 212 Contents 9 6.4.2 Content Modification— Local, Intermediate, and in the Main DRS . 215 6.4.3 Preferences .......................... 220 6.5 The Extended Theory Applied . 226 6.5.1 Binding Relative to an Overt Antecedent . 227 6.5.2 Nonpresupposing Conditional . 229 6.5.3 Presupposing Conditional— Introducing Local Justification Conditions . 231 6.5.4 Trapping through Direct Binding . 233 6.5.5 IntermediateReadings . 235 6.5.6 Bridging............................ 237 6.5.7 Nonpresupposing Disjunction . 241 6.5.8 Denial ............................. 244 6.6 Conclusion............................... 248 7 Conclusion 253 A A Fine-grained Compositional DRT 259 B Axioms of the Grammar 269 Bibliography 277 Summary 291 Curriculum Vitae 295 Chapter 1 Introduction Anyone can tell that conversations and texts have meanings. They come with some content which is conveyed from the speaker or writer to the hearer or reader of the discourse. Moreover, it does not take long to see that texts and conversations are built up from smaller units, such as sentences, phrases, and words, and that there is some sort of systematic relation between the composition of a text or conversation from smaller units and its meaning. Clearly, the text in (1.1a) does not mean the same thing as the one in (1.1b). (1.1) a. Jack opened the door. He turned on the light. b. Jack turned on the light. He opened the door. The order of the sentences matters. From (1.1a) we conclude that Jack turned on the light after he opened the door. Furthermore, we tend to assume that the light he turns on is a light in the room he just opened a door of. This presupposes that before Jack opened the door and turned on the light, the light was off. In fact, in order to turn on the light, he must partly or completely have entered the room, so it is likely that just after he turned on the light he is in the room. From (1.1b) we conclude that Jack turned on the light before he opened the door. The light he turns on must be a light in the corridor or location outside the room of which he opens a door. This light must have been off, before Jack turned it on. It is not clear whether Jack enters the room. If we think of the discourse in (1.1b) as a short narrative, or a description of what happened, that description ends just after Jack opens the door. The example illustrates, in a nutshell, what are the main concerns of discourse theory. If a language user reads a text, or takes part in a conversation, he con- structs a meaning or interpretation of it in his mind. Conversely, if he wants to write a text, or contribute to a conversation, he translates what he has in mind into words and sentences. Discourse theory investigates the systematic relation between linguistic form and meaning, in particular where the construction and interpretation of larger discourse units is concerned. 11 12 CHAPTER 1. INTRODUCTION It tries to explain how language users handle implicitness in discourse, that is, how they fill in what is not explictly said and obtain cohesive interpretations. It offers an analysis of the context dependence of sentences in their discourse context. It addresses, for instance, the particular contribution to discourse meaning of words and phrases that link up to events or individuals previously mentioned in the discourse. These are called anaphors. The pronoun ‘he’ in (1.1a-b) is an examples of this. Definite noun phrases, such as ‘the light’ and ‘the door’, are sometimes called anaphors as well. They refer to entities which are ‘given’, or can presumed to be present in the context of interpretation. Because they tell us something about what the speaker or writer presupposes to be the case they are also often categorised as presupposition triggers. Sometimes an anaphor has an explicit antecedent, that is, a word or phrase that precedes it in the discourse, and which introduces the entity it refers to. For example, in (1.1a-b) ‘Jack’ is the antecedent of ‘he’. Discourse grammar is a branch of discourse theory which most rigorously im- plements the idea that discourse is composed of clauses and larger discourse units just like sentences are composed of words and phrases. Discourse, like sentences, has syntactic structure, and the construction of discourse is rule-based. While the meaning of a sentence is composed of the meanings of the words it consists of, the meaning of a discourse is composed of the meanings of sentences and so- called discourse relations.