Underspecified semantics
pp. 311-338
in: Klaus Von Heusinger, Urs Egli (eds), Reference and anaphoric relations, Berlin, Springer, 2000Abstract
Ambiguities in natural language can multiply so fast that no person or machine can be expected to process a text of even moderate length by enumerating all possible disambiguations. A sentence containing n scope bearing elements which are freely permutable will have n! readings, if there are no other, say lexical or syntactic, sources of ambiguity. A series of m such sentences would lead to (n!)m possibilities. Some alternative scopings may boil down to the same reading. The relative order in which we scope two existentially quantified noun phrases, for example, will not matter if no other material intervenes. But all in all the growth of possibilities will be so fast that generating readings first and testing their acceptability afterwards will not be feasible. This insight has led a series of researchers (e.g. Schubert & Pelletier 1982, Hobbs 1982, 1983, Nerbonne 1992, Alshawi & Crouch 1992, Reyle 1993,1995, Poesio 1994, Pulman 1994, Muskens 1995a, Pinkal 1997, 1996) to adopt a level of representation at which ambiguities remain unresolved. The idea here is not to generate and test many possible interpretations but to first generate one "underspecified" representation which in a sense represents all its complete specifications and then use whatever information is available to further specify the result. Some mechanism of reasoning, presumably a mechanism with a monotonic core but also allowing "jumping to conclusions", must strengthen the original underspecified representation of a given sentence until it is either equivalent to a unique reading for that sentence or until its possible further specifications are within some otherwise acceptable range.