It has long been noted that Natural Language utterances can communicat
e more than their conventional meaning (Grice, 1975). It has also been
noted that behaving appropriately in response to instructions given i
n Natural Language requires understanding more than their conventional
meaning (Suppes & Crangle, 1988; Webber & Di Eugenio, 1990; Webber et
al., 1992). This paper addresses one mechanism by which speakers conv
ey, and hearers derive, such additional aspects of meaning - a mechani
sm we call pragmatic overloading. In pragmatic overloading, a clause i
nterpreted as conveying directly or indirectly the goal beta of an act
ion alpha which is described by some other clause, forms the basis of
constrained inference that leads to additional information about the a
ction alpha. The paper demonstrates pragmatic overloading through a va
riety of clausal adjuncts. We then discuss a framework that supports m
any of the inferences that pragmatic overloading gives rise to. This f
ramework integrates a lexical semantics representation a la Jackendoff
(1990) with a knowledge representation system, CLASSIC (Brackman et a
l., 1991) based on description logic. We give examples of its use, bef
ore concluding with a discussion of future work.