Presuppositions and Pronouns - Nijmegen Centre for Semantics

Presupposition 21
recipient of this sentence will usually be entitled to conclude that the sender
takes (38b) to be false, because he may reason as follows: (i) Presumably, the
speaker knows what he is talking about, and therefore he knows how many
girls Fred kissed; (ii) if the speaker had known (38b) to be true, he would
surely have produced this sentence instead of (38a); but (iii) since he hasn't
done that, it follows from (i) and (ii) that he takes (38b) to be false.
If some such story can be told about (38a), a strictly parallel story can be
told about (39a), which embeds (38a). Here is how: (i) Presumably, the
speaker knows what he is talking about, and therefore he knows how many
girls Wilma believes were kissed by Fred; (ii) if the speaker had known (39b)
to be true, he would surely have produced this sentence instead of (39a); but
(iii) since he hasn't done that, it follows from (i) and (ii) that he takes (39b)
to be false. Note that this account is given without reference to the
circumstance that in (39a), the quantified NP some of the girls occurs in an
embedded position. The crucial premise for this line of explanation is that
(38a) and (39a) become stronger statements when all is substituted for some;
the notion of embedding doesn't enter the picture in any way.
There is a further reason why it is wrong to describe the inferences in (38)
and (39) as instances of implicature projection. If these really were instances
of projection in the relevant sense, then the inference from (39a) to (39b)
would be beside the point, since the crucial prediction would be that (39a)
will normally imply (38b). For, after all, projection means that the same
inference tends to through in all sorts of linguistic environments. But
evidently (39a) does not normally imply that (38b) is true.
There are cases that might be construed as instances of implicature
projection, but only when taken at face value. The following is such a case:
(40) It is possible that Fred kissed some of the girls.
This will tend to be heard as implying that, according to the speaker, Fred
didn't kiss all the girls. But, again, this inference can be accounted for, along
the lines set out by Grice, without anything like a projection mechanism
entering the scene. Clearly, (40) is weaker than:
(41) It is possible that Fred kissed all of the girls.
So if a speaker utters (40) instead of (41), he presumably takes the latter to
be false, which entails that he doesn't believe that Fred kissed all the girls, i.e.
he believes that (38b) is true. Again, no need for a notion of implicature
projection. Furthermore, the inference vanishes without a trace if we replace
the epistemic modal with, say, a deontic one:
(42) Fred was given permission to kiss some of the girls.
A hearer who takes this to imply that (38b) is true must be assuming that
Fred is an obedient boy, but it is clear that this will not be inferred by default.