Sergei Nirenburg, Victor Raskin, Boyan Onyshkevych
Treatment of meaning in NLP is greatly facilitated if semantic analysis and generation systems rely on a language-neutral, independently motivated world model, or ontology. However, the benefits o3 the ontology are somewhat offset in practice by the difficulty ot its acquisition. This is why a number of computational linguists make a conscious choice to bypass ontology in their semantic deliberations. This decision is often justiffed by questioning the pr~hdples underlying ontologies and by challenging, the ontology-b~ised semantic enterprise on the groun~ls of its ostensible irreprodudbilfty. In this paper we illustrate, on the example of the lexicon entry for the Spani~ verb dejar, the expressive power of lexical-semantic descriptions based on the ontology used in the MikroIeosmos machine translation project. ~ expressive power is compared with that of some of the non-ontological approaches to lexical semantics. We _argue that these approaches in reality rely on ontol6gies in everyt~_'._g but r~me. We offer a view of ontoIogies as theories of lexical-semantic descriptions. We posit that no underlying prindples for ontologies are possible and explain why the charge of irreproducibility is not valic[.