Conventional implicatures

Grice actually spent little time discussing conventional implicatures, which he characterized as being implicated by particular words or expressions such as but or even, rather than being part of their truth-conditional content (Grice [1975]1989: 25). What Grice meant in claiming conventional implicatures are not part of the truth-conditional content arising from an utterance was that such expressions are not straightforwardly truth-evaluable, that is, they cannot be evaluated against real-world conditions, and so the meaning representation in question properly belongs to the speaker. For example, if someone claims the weather today is sunny but cold, then he or she is committed to two distinct claims that can be evaluated against real-world conditions, that is, (1) it is sunny as opposed to cloudy or raining, and (2) the temperature is (relatively) cold as opposed to warm or hot. The additional claim that these two conditions (i.e. the weather today being sunny and cold) somehow contrast with each other, however, is not truth-evaluable against real-world conditions, but rather constitutes a stance taken by the speaker. For this reason, Grice treated this sense of contrast indicated through but as a conventional implicature rather than part of what is said.

The notion of conventional implicature has been relatively neglected in pragmatics (although see Levinson 1979b; Potts 2005), and has even been criticized as theoretically superfluous or unnecessary (Bach 1999; Wilson and Sperber 1993). However, an examination of examples of conventional implicatures in discourse points to the pivotal role they can play in interaction. Consider the following example from the novel High Fidelity (which is here reformatted like a fi lm script):