Paul Grice and the philosophy of language

522 STEPHEN NEALE
honesty). The implication in question Grice calls a conventional implicature.
By uttering (1) U has conventionally implicated that (e.g.) her poverty
should be contrasted with her honesty.
Grice's idea is that by uttering (1) U is performing two speech acts: U
is saying that she is poor and she is honest; additionally, U is indicating
or suggesting that someone (perhaps U) has a certain attitude toward
what is said. 14 Unfortunately, Grice does not develop this idea and we
are left with just the claim that a conventional implicature is determined
(at least in part) by the (conventions governing) the words used. 15
In 'The Causal Theory of Perception', Grice points out that the sort of
implication we have just been considering is not a presupposition (as
originally defined by Strawson and adopted by others)./3 is a presupposition
of a, just in case the truth or falsity of a requires the truth of/3. (If
the truth of a requires the truth of/3, but the falsity of a does not, /3 is
an entailment of a). More precisely, if a presupposes /3, a lacks a truth
value if 13 is false. But as Grice points out, in the case of an utterance of
(1)
•.. even if the implied proposition were false, i.e., if there were no reason in the world to
contrast poverty with honesty either in general or in her case, the original statement could
still be false; it would be false for example if she were rich and dishonest. One might perhaps
be less comfortable about assenting to its truth if the implied contrast did not in fact obtain;
but the possibility of falsity is enough for the immediate purpose (1961, p. 127) 16
So the implication in question is not a presupposition, at least not on the
standard semantic conception of that notion. 17
A moment ago, I alluded to a proviso concerning the equation of what
is said with the proposition expressed (or the statement made). Anyone
who reads 'Logic and Conversation' and 'Further Notes' in isolation from
the rest of the William James Lectures, is almost certain to miss the
14 Taken this way, conventional implicature would seem very close to what Frege calls
"coloring" or "tone". According to Frege, the connectives 'and' and 'but' have the same
sense (as do the nouns 'horse' and 'steed') but differ in coloring. Together with other features
of Frege's theory, this ensures that substituting 'but' for 'and' in a sentence will not lead to
a difference in sense or a difference in truth value (reference).
15 The qualifier "at least in part" is needed because in many cases the particular conversational
context will play a role in determining the precise content of a conventional implicature.
16 Again, I quote from the section of 'The Causal Theory of Perception' not reproduced in
Studies.
27 At this stage, Grice leaves it open whether or not there is some other "pragmatic" notion
of presupposition, distinct from implicature, that is of any theoretical utility• It is ultimately
Grice's view that any alleged presupposition is either an entailment or an implicature, and
hence the notion of presupposition, to the extent it was ever coherent, can be dispensed
with altogether.