Donnellan's Distinction and a Computational Model of Reference

In this paper, I describe how Donnellan's distinction between referential and attributive uses of definite descriptions should be represented in a computational model of reference. After briefly discussing the significance of Donnellan's distinction, I reinterpret it as being three-tiered, relating to object representation, referring intentions, and choice of rehrring expression. I then present a cognitive model of referring, the components of which correspond to this analysis, and discuss the interaction that takes place among those components. Finally, the implementation of this model, now in progress, is described. I N T R O D U C T I O N It is widely acknowledged that Donnellan's distinction [7] between referential and attributive uses of definite descriptions must be taken into account in any theory of reference. There is not yet agreement, however, as to where the distinction fits in a theoretical model of definite noun phrases. For Cohen [4], the intention that the hearer identify a referent constitutes a crucial difference between the referential and the attributive. Barwise and Perry [3], on the other hand, treat their value-loaded/value-free distinction as the central feature of the referential versus the attributive. However, as pointed out by Grosz et al. [9], this analysis ignores an essential aspect of Donnellan's distinction, namely, the speaker's ability, when using a description referentially, to refer to an object that is independent of the semantic denotation. The problem of determining the correct interpretation of Donnellan's distinction is of considerable importance. First, Donnellan's distinction seems to violate the principle that reference to physical objects is achieved by virtue of the descriptive content of referring expressions. This principle can be found practically everywhere for example, in Frege's sense and reference, Rusell's theory of descriptions, and Searle's speech acts. In the referential use of definite descriptions, however, reference seems to be established independently of descriptive content. If I say ~The man over there with a glass of white wine is..., ~ I may be successful in my act of referring regardless of whether the person over there is a man or a woman, the glass is full of wine or grape juice, the color of the beverage is white or red, and so on. This, if accepted, has far-reaching consequences for the meaning of referring expressions, for the logical structure of propositions, and for the theory of propositional attitudes. Second, the referential/attributive distinction forces us to reconsider the division between semantics and pragmatics. It seems that a speaker's intentions in using a referring expression do make a semantic difference. If I say ~Smith's murderer is insane," meaning that whoever murdered Smith is insane (the attributive case), what I say is true if and only if the one and only murderer is insane. If, on the other hand, my intention is to use the definite description referentially (referring to, say, Tom, who is accused of being the culprit), what I say is true if and only if Torn is indeed insane whether he is the murderer or not. Unless we understand the interaction between conventional meaning and a speaker's intentions in such cases, we cannot hope to construct an adequate model of referring and language use in general. Finally, Donnellan's distinction brings to the fore the role of identification in the speech act of referring. Both Strawson and Searle ([17,16]) attempted to analyze referring in terms of identification and identifying descriptions. But Donnellan has pointed to what seems to be a clear distinction between eases in which identification is required (referential use) and t h o r in which it is not (attributive use). This calls for a new analysis of the speech act of referring, one that does not rely on identification as a central concept, l In this paper, I present a general framework for treating Donnellan's distinction. In particular, I contend the following: 1. The apparent simplicity of the referential/attributive distinction masks three aspects of the problem of reference. In a sense, it is not one distinction but three: the first has to do with representations of objects, the second with referring intentions, the third with the choice of referring expressions. 2. These three distinctions are independent of one another, and should be handled separately. Each is relevant to a different component of a plan-based model of reference: the data base, the planner, and the utterance generator, respectively. 3. Although the three distinctions are mutually independent, tThese comments, naturally, only touch the surface. For an extensive discussion of the significance of the referential /at tr ibutive distinction see my thesis [141. For a discussion of the role of identification in referring, see the paper coauthored by Appel t and me on this topic 12].