The Semantics and Pragmatics of Presupposition

This talk is based on joint research with Nicholas Asher.  I will
offer a novel analysis of presuppositions, paying particular attention
to the interaction between the knowledge resources that are required
to interpret them.  The analysis has two main features.  First, I
capture an analogy between presuppositions, anaphora and scope
ambiguity (cf. van der Sandt, 1992), by utilising semantic
underspecification (cf. Reyle, 1993).  Second, resolving this
underspecification requires reasoning about how the presupposition is
rhetorically connected to the discourse context.

This has several consequences.  First, since pragmatic information
plays a role in computing the rhetorical relation, it also constrains
the interpretation of presuppositions.  Our account therefore goes
beyond existing ones, and provides a forum for analysing problematic
data, that require pragmatic reasoning.  Second, binding
presuppositions to the context via rhetorical links replaces
accommodating them, in the sense of adding them to the context
(cf. Lewis, 1979).  Thus, unlike previous theories, I don't resort to
interpretation mechanisms that are peculiar to presuppositions.
Rather, they are handled entirely in terms of the discourse update
procedure.

I will formalise this approach in SDRT (Asher 1993, Lascarides and
Asher 1993), but I won't assume any prior knowledge of this
framework.  I will assume prior knowledge of DRT and what
presuppositions are.

If you would like to read the paper that this talk is based on in
advance of the meeting, then you can pick it up at: 

	http://www.cogsci.ed.ac.uk/~alex/papers/presupposition.ps