Presuppositions and Pronouns - Nijmegen Centre for Semantics

182 Presuppositions and Pronouns
utterance has a hypothetical common ground suggested by the immediately
preceding context' (ibid.); and finally (iii) modal subordination may not
make available to anaphoric expressions antecedents that have no explicit
representation in the given DRS (1989: 705).
Roberts's first constraint restricts modal subordination to utterances in
non-factual mood. This constraint is needed to explain why the second it in
(17) cannot link up to the indefinite a bear. bear:
(17) Fred may have seen a bear^. i . It/s It-'s a big one.
This example shows quite clearly that, without any further constraints, the
notion of antecedent accommodation nullifies the restrictions that DRT
imposes on anaphoric reference. Pending rather severe restrictions, any
theory which adopts antecedent accommodation is a null theory of anaphora,
which predicts that anything goes, and the constraints Roberts proposes are
intended to regain the effect of DRT's accessibility restriction.
The non-factuality constraint excludes the anaphoric link in (17) on the
grounds that the second sentence is 'factual', which in this case correlates
with the absence of an overt modal expression. However, Roberts's non-
nonfactuality
constraint is weaker than it might appear to be at first sight,
because she does not want to restrict modal subordination to sentences that
contain overt modal operators. For example, she doesn't want this constraint
to frustrate her analysis of (10), and postulates accordingly that on
'pragmatic grounds, we may assume that neither disjunct of a disjunction is
asserted, and hence that both are nonfactual.' (1989: 702) It would seem,
therefore, that this constraint is not nearly restrictive enough, because it
allows modal subordination of any non-entailed clause, as in the following:
(18) a. Gurnemanz may have bought a new swordi. Kundry thinks
that iti is too heavy for him.
b. Fred may have seen a bear^.. t
Iti It; can dance.
In these cases modal subordination does not seem to be possible. But as both
examples obey the non-factuality constraint, Roberts's theory does not
exclude this possibility. It would seem advisable, therefore, to strengthen this
constraint by restricting modal subordination to sentences that contain overt
modals, or that at least are interpreted as modals.
Roberts's second constraint requires that accommodated material be
'fresh' and hence must be copied from a recent portion of the discourse
representation. It is this constraint, presumably, that applies to discourses
like the following:
(19) A thief might try to break in. So we should tell our neighbour that
we're away for the weekend, and unchain the dog before we go out.
If that doesn't scare him off, nothing will.