Temporal Relations in English and German Narrative Discourse
Understanding the temporal relations which hold between situations described in a narrative is a highly complex process. The main aim of this thesis is to investigate the factors we have to take into account in order to determine the temporal coherence of a narrative discourse. In particular, aspectual information, tense, and world and context knowledge have to be considered and the interplay of all these factors must be specified. German is aspectually speaking an interesting language, because it does not possess a grammaticalised distinction between a perfective and imperfective aspect. In this thesis I examine the German aspectual system and the interaction of the factors which have an influence on the derived temporal relation for short discourse sequences. The analysis is carried out in two steps: First, the aspectual and temporal properties of German are investigated, following the cross-linguistic framework developed by Carlota S. Smith. An account for German is given which emphasises the properties which are peculiar to this language and explains why it has to be treated differently to, for example, English. The main result for the tense used in a narrative text—the Preterite—is that information regarding the end point of a described situation is based on our world knowledge and may be overridden provided context knowledge forces us to do this. Next, the more complex level of discourse is taken into account in order to derive the temporal relations which hold between the described situations. This investigation provides us with insights into the interaction of different knowledge sources like aspectual information as well as world and context knowledge. This investigation of German discourse sequences gives rise to the need for a time logic which is capable of expressing fine as well as coarse (or underspecified) temporal relations between situations. An account is presented to describe exhaustively all conceivable temporal relations within a computationally tractable reasoning system, based on the interval calculus by James Allen. However, in order to establish a coherent discourse for larger sequences, the hierarchical structure of a narrative has to be considered as well. I propose a Tree Description Grammar — a further development of Tree Adjoining Grammars — for parsing the given discourse structure, and stipulate discourse principles which give an explanation for the way a discourse should be processed. I furthermore discuss how a discourse grammar needs to distinguish between discourse structure and discourse processing. The latter term can be understood as navigating through a discourse tree, and reflects the process of how a discourse is comprehended. Finally, a small fragment of German is given which shows how the discourse grammar can be applied to short discourse sequences of four to seven sentences. The conclusion discusses the outcome of the analysis conducted in this thesis and proposes likely areas of future research.