Reambiguating: on thenon-monotonicity of disambiguation

The relation between lexical ambiguity and disambiguation ismostly approached from an intra-sentential perspective. Thus, when analyzing the ambiguity and disambiguation of a lexical item, one tends to study its variance in interpretation when it is modified by or occurs as an argument of other lexical items. Broadening this perspective, this paper shows that there are important insights into the nature of disambiguation to be gained by studying more closely how ambiguous expressions behave in contexts spanningmore than one sentence. More specifically, we introduce new data involving anaphora resolution with the following two characteristics: (i) a potentially ambiguous antecedent which is disambiguated in its local context, and (ii) anaphora which refer to one of the possible readings of the antecedent which was not selected in the local antecedent context. We argue that these data call for a revision of how we conceive of and formalize the process of disambiguation, introducing the notion of reambiguation, which characterizes the process of reintroducing alternative interpretations which were originally excluded by disambiguation. The paper is structured as follows. In Section 2, we discuss properties of ambiguity and disambiguation. We also give an informal overview of our approach, including a discussionof the notionof reambiguation. In Section 3, the formal basis of our analysis is presented. In Section 4, we present the analysis and discuss some consequences of our approach for formal discourse semantics in general. Section 5 concludes the paper.