Presuppositions in Spoken Discourse

Chapter 2
because constraints on the acceptability of the discourse do the same task that
clausal implicatures did in Gazdar’s approach.
Since this earlier work there have been some new developments in semantics
and semantic theories. Earlier theories of presupposition explained their
approaches in terms of semantic theories that treated meaning in a static way.
Current popular approaches to presupposition are dynamic in that they use theories
that consider meaning to be the way information changes the context. The two
main theories of presupposition popular today, the binding theory and the
satisfaction theory, are extensions of dynamic theories of meaning, i.e. Discourse
Representation Theory and Context Change Semantics respectively. These dynamic
frameworks help to solve some of the problems with earlier theories of
presuppositional projection. The following two sections introduce these two central
theories, and the extensions of them for treating presupposition, the binding theory
and the satisfaction theory.
2.3 PRESUPPOSITIONS AS ANAPHORS
The basic claim of the binding theory of presupposition, first developed in van der
Sandt (1992), is that presuppositions and anaphors are the same kind of thing and
can be resolved by similar methods. Other developments of the theory are Geurts
(1999) and (Kamp & Rossdeutscher, 1997). The theory extends Discourse
Representation Theory (DRT, Kamp & Reyle 1993) with a mechanism for
resolving presuppositions and many of the ideas in the binding theory are
intimately connected with the philosophy behind DRT. In the next section, I first
briefly present DRT followed by a detailed presentation of the binding theory.
2.3.1 Discourse Representation Theory
DRT differs from earlier semantic representations such as predicate logic and
Montague Grammar in that it is able to represent extended discourses because it
permits a sentence by sentence incremental update of the representation. In DRT
we create a representation from the discourse and then we interpret this
representation with respect to a model. The process by which the representation is
created and the process by which it is interpreted are separate. The representation
is thus essential for interpretation. This is one of the key ways DRT differs from
e.g. Montague Grammar and Context Change Semantics, which do not need an
intermediate level of representation in order to be interpreted.
The key components of a DRT representation are - discourse representation
structures or DRSs. Linguistic expressions in a discourse are decoded into elements
in the DRS representation. DRSs are made up of two types of objects, reference
markers, which represent individuals in the discourse, and DRS-conditions which
encode descriptive information about the individuals in the discourse, and look
quite similar to predicates with the reference markers serving as arguments. A DRS
can also be a condition.
In interpretation, the reference markers in the representation are associated
with individuals in a model and the DRS-conditions in the representation represent
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