Lexical Pragmatics - Journal of Semantics

Reinhard Blutner 145the probabilistic interpretation of costs, but we will not refrain from usingfactoring. Factoring some literals obtained by backward chaining can beproved to be a very useful operation in natural language interpretation (cf.Stickel 1989).It is now possible to incorporate the abductive component in the generalpragmatic framework viewing natural language interpretation as inferencesto pragmatically licensed updates. For simplicity's sake let me illustrate theincorporation of abduction by way of an elementary example. This gives methe opportunity to discuss some crucial differences between the presentapproach and the Hobbs-Stickel account where natural language interpretationis viewed as abductive inference to the best explanation. In order tosimplify matters, I will exclude effects of blocking via the Q-principle. Thatmeans, I will assume that there are no expression alternatives a' that mayblock any interpretation of a.Let us assume a knowledge base as presented in (27) and let us accept thatall axiom costs are zero.(*7)Thethe(28)eg: C 2-> sD 1D 1A A O S -> CA B 0 5 - > ADdiagram (28) shows the abductive inference graph when (27) is taken ascommon ground and sem(a) = S is taken as the starting clause.D 1TDAD 1TAB 0 - 5 ->A 051 1A->CC 2 -t 1g$IOT [Assuming C:2 • $10 = $20][Assuming A:[Assuming B:0.5 • $10 = $5]Downloaded from http://jos.oxfordjournals.org/ by guest on September 12, 2014The resulting set of abductive variants is presented in (29a) and the costsassociated with these variants are given in (29b).(29) (a) C(S) = {A,B,C}(b) c(S,A) = $io,c(S,B) = $5,c(S,C) = $20(c) p(S) = {B}(d) cg[S] = eg U {B}