Implicature is a nonlogical inference constituting part of what is conveyed by S[peaker] in uttering U within context C, without being part of what is said in U. As stressed by H. PAUL GRICE (1989), what is conveyed is generally far richer than what is directly expressed; linguistic MEANING radically underdetermines utterance interpretation. Pragmatic principles must be invoked to bridge this gap, for example, (1) (Harnish 1976: 340):

Make the strongest relevant claim justifiable by your evidence.

Precursors of (1) were proposed by Augustus De Morgan and John Stuart Mill in the mid-nineteenth century, and by P. F. Strawson and Robert Fogelin in the mid-twentieth (see Horn 1990), but the central contribution is Grice's, along with the recognition that such principles are not simply observed but rather systematically exploited to generate nonlogically valid inferences. From S's assertion that Some of the apples are ripe, H[earer] will tend to infer that (for all S knows) not all the apples are ripe, because if S had known all were ripe, she would have said so, given (1).

The first explicit and general account of such inferences is given by Grice (1961: §3), who distinguishes the nonentailment relations operative in (2):

a. She is poor but honest.
a'. There is some contrast between her poverty and her honesty.
b. Jones has beautiful handwriting and his English is grammatical. [Context: recommendation letter for philosophy job candidate]
b'. Jones is no good at philosophy.
c. My wife is either in the kitchen or in the bathroom.
c'. I don't know for a fact that my wife is in the kitchen.

Grice observes that although the inference in (2a, a') cannot be cancelled (#She is poor but honest, but there's no contrast between the two), it is detachable, because the same truth-conditional content is expressible in a way that detaches (removes) the inference: She is poor and honest. It is also irrelevant to truth conditions: (2a) is true if "she" is poor and honest, false otherwise. Such detachable but noncancelable inferences that are neither constitutive of what is said nor calculable in any general way from what is said are conventional implicata, related to pragmatic presuppositions (see PRAGMATICS). Indeed, classic instances of conventional implicature involve the standard pragmatic presupposition inducers: focus particles like even and too, truth-conditionally transparent verbs like manage to and bother to, and syntactic constructions like clefts. Because conventional implicata are non-truth-conditional aspects of the conventional meaning of linguistic expressions, which side of the semantics/pragmatics border they inhabit depends on whether pragmatics is identified with the non-truth-conditional (as on Gazdar's intentionally oversimplified equation: pragmatics = semantics - truth conditions) or with the nonconventional. (Karttunen and Peters 1979 provide a formal compositional treatment of conventional implicature.)

The inferences associated with (2b,c) are nonconventional, being calculable from the utterance of such sentences in a particular context. In each case, the inference of the corresponding primed proposition is cancelable (either explicitly by appending material inconsistent with it -- "but I don't mean to suggest that . . ." -- or by altering the context of utterance) but nondetachable, given that truth-conditionally equivalent expressions license the same inference. An utterance of (2b) "does not standardly involve the implication . . . attributed to it; it requires a special context to attach the implication to its utterance" (Grice 1961: 130), whereas the default inference from (2c), that S did not know in which of the two rooms his wife was located, is induced in the absence of a marked context (e.g., that of a game of hide-and-seek). (2b) exemplifies particularized conversational implicature, (2c) the more linguistically significant category of generalized conversational implicature. In each case, it is not the proposition or sentence, but the speaker or utterance, that induces the relevant implicatum in the appropriate context.

Participants in a conversational exchange compute what was meant (by S's uttering U in context C) from what was said by assuming the application of the cooperative principle (Grice 1989: 26) -- "Make your conversational contribution such as is required, at the stage at which it occurs" -- and the four general and presumably universal maxims of conversation on which all rational interchange is grounded:

Maxims of Conversation (Grice [1967] 1989: 26-27):
Quality: Try to make your contribution one that is true.
  1. Do not say what you believe to be false.
  2. Do not say that for which you lack evidence.
  1. Make your contribution as informative as is required (for the current purposes of the exchange).
  2. Do not make your contribution more informative than is required.
Relation: Be relevant.
Manner: Be perspicuous.
  1. Avoid obscurity of expression.
  2. Avoid ambiguity.
  3. Be brief. (Avoid unnecessary prolixity.)
  4. Be orderly.

Although implicata generated by the first three categories of maxims are computed from propositional content (what is said), Manner applies to the way what is said is said; thus the criterion of nondetachability applies only to implicata induced by the "content" maxims.

Since this schema was first proposed, it has been challenged, as well as defended and extended, on conceptual and empirical grounds (Keenan 1976; Brown and Levinson 1987), while neo- and post-Gricean pragmaticists have directed a variety of reductionist efforts at the inventory of maxims. The first revisionist was Grice himself, maintaining that all maxims are not created equal, with a privileged status accorded to Quality (though see Sperber and Wilson 1986 for a dissenting view): "False information is not an inferior kind of information; it just is not information . . . . The importance of at least the first maxim of Quality is such that it should not be included in a scheme of the kind I am constructing; other maxims come into operation only on the assumption that this maxim of Quality is satisfied" (Grice 1989: 371).

Of those "other maxims," the most productive is Quantity-1, which is systematically exploited to yield upper-bounding generalized conversational implicatures associated with scalar operators (Horn 1972, 1989; Gazdar 1979; Hirschberg 1985). Grice seeks to defend a conservative bivalent semantics; the shortfall between what standard logical semantics yields and what an intuitively adequate account of utterance meaning requires is addressed by a pragmatic framework grounded on the assumption that S and H are observing CP and the attendant maxims. Quantity-based scalar implicature in particular -- my inviting you to infer from my use of some . . . that for all I know not all . . . -- is driven by your knowing (and my knowing your knowing) that I expressed a weaker proposition, bypassing an equally unmarked utterance that would have expressed a stronger proposition, one unilaterally entailing it. What is said in the use of a weak scalar value is the lower bound (at least some, at least possible), with the upper bound (at most some, at most necessary) implicated as a cancelable inference (some and possibly all, possible if not necessary). Negating such predications denies the lower bound: to say that something is not possible is to say that it is impossible (less than possible). When the upper bound is denied (It's not possible, it's necessary), grammatical and phonological diagnostics reveal a metalinguistic or echoic use of negation, in which the negative particle is used to object to any aspect of a quoted utterance, including its conventional and conversational implicata, register, morphosyntactic form or pronunciation (Horn 1989; Carston 1996).

One focus of pragmatic research has been on the interaction of implicature with grammar and the LEXICON, in particular on the conventionalization or grammaticalization of conversational implicatures (see Bach and Harnish 1979 on standardized nonliterality). Another issue is whether Grice's inventory of maxims is necessary and sufficient. One response is a proposal (Horn 1984, 1989; see also Levinson 1987) to collapse the non-Quality maxims into two basic principles regulating the economy of linguistic information. The Q Principle, a hearer-based guarantee of the sufficiency of informative content ("Say as much as you can, modulo Quality and R"), collects Quantity-1 and Manner-1,2. It is systematically exploited (as in the scalar cases) to generate upper-bounding implicata, based on H's inference from S's failure to use a more informative and/or briefer form that S was not in a position to do so. The R Principle, a correlate of the law of least effort dictating minimization of form ('Say no more than you must, modulo Q'), encompasses Relation, Quantity-2, and Manner-3,4. It is exploited to induce strengthening (lower-bounding) implicata typically motivated on social rather than purely linguistic grounds, as exemplified by indirect speech acts (e.g., euphemism) and so-called neg-raising, as in the tendency to pragmatically strengthen I don't think that f to I think that not-f.

A more radically reductionist model is offered in relevance theory (Sperber and Wilson 1986), in which one suitably elaborated principle of RELEVANCE suffices for the entire gamut of inferential work performed by the Gricean maxims. (The monistic approach of RT is closer to the dualistic Q/R model than it appears, both frameworks being predicated on a minimax or cost/benefit tradeoff that sees the goal of communication as maximizing contextual effects while minimizing processing effort.) RT stresses the radical underspecification of propositional content by linguistic meaning; pragmatically derived aspects of meaning include not only implicatures but "explicatures," that is, components of enriched truth-conditional content.

Although the issues surrounding the division of labor between Gricean implicature and RT-explicature await resolution (see Horn 1992; Récanati 1993), relevance theory has proved a powerful construct for rethinking the role of pragmatic inferencing in utterance interpretation and other aspects of cognitive structure; see Blakemore (1992) for an overview.

See also

Additional links

-- Laurence Horn


Bach, K., and R. M. Harnish. (1979). Linguistic Communication and Speech Acts. Cambridge, MA: MIT Press.

Blakemore, D. (1992). Understanding Utterances. Oxford: Blackwell.

Brown, P., and S. C. Levinson. (1987). Politeness: Some Universals in Language Usage. Cambridge: Cambridge University Press.

Carston, R. (1996). Metalinguistic Negation and Echoic Use. Journal of Pragmatics 25:309-330.

Gazdar, G. (1979). Pragmatics. New York: Academic Press.

Grice, H. P. (1961). The causal theory of perception. Proceedings of the Aristotelian Society, sup. vol. 35:121-152.

Grice, H. P. (1989). Studies in the Way of Words. Cambridge: Harvard University Press.

Harnish, R. M. (1976). Logical form and implicature. In S. Davis, Ed., Pragmatics: A Reader. New York: Oxford University Press, pp. 316-364.

Hirschberg, J. (1985). A Theory of Scalar Implicature. Ph.D. diss., University of Pennsylvania.

Horn, L. (1972). On the Semantic Properties of Logical Operators in English. Ph.D. diss., UCLA. Distributed by Indiana University Linguistics Club, 1976.

Horn, L. (1984). Toward a new taxonomy for pragmatic inference: Q-based and R-based implicature. In D. Schiffrin, Ed., Meaning, Form, and Use in Context (GURT '84). Washington: Georgetown University Press, pp. 11-42.

Horn, L. (1989). A Natural History of Negation. Chicago: University of Chicago Press.

Horn, L. (1990). Hamburgers and truth: Why Gricean inference is Gricean. Berkeley Linguistics Society 16:454-471.

Horn, L. (1992). The said and the unsaid. Proceedings of the Second Conference on Semantics and Linguistic Theory: 163-192.

Karttunen, L., and S. Peters. (1979). Conventional implicature. In C.-K. Oh and D. Dinneen, Eds., Presupposition. Syntax and Semantics, vol. 11. New York: Academic Press, pp. 1-56.

Keenan, E. O. (1976). The universality of conversational postulates. Language in Society 5:67-80.

Levinson, S. C. (1987). Minimization and conversational inference. In J. Verschueren and M. Bertucelli-Papi, Eds., The Pragmatic Perspective. Amsterdam: John Benjamins, pp. 61-130.

Récanati, F. (1993). Direct Reference. Oxford: Blackwell.

Sperber, D., and D. Wilson. (1986). Relevance. Cambridge, MA: Harvard University Press.

Further Readings

Atlas, J. D., and S. C. Levinson. (1981). It-clefts, informativeness, and logical form. In P. Cole, Ed., Radical Pragmatics. New York: Academic Press, pp. 1-61.

Bach, K. (1994). Conversational implicature. Mind and Language 9:125-162.

Carston, R. (1988). Implicature, explicature, and truth-theoretic semantics. In S. Davis, Ed., Pragmatics: A Reader. New York: Oxford University Press, pp. 33-51.

Cole, P., Ed. (1978). Syntax and Semantics 9: Pragmatics. New York: Academic Press.

Davis, S., Ed. (1991). Pragmatics: A Reader. New York: Oxford University Press.

Green, G. (1989). Pragmatics and Natural Language Understanding. Hillsdale, NJ: Erlbaum.

Green, G. (1990). The universality of Gricean explanation. Berkeley Linguistics Society 16:411-428.

Levinson, S. C. (1983). Pragmatics. Cambridge: Cambridge University Press.

Levinson, S. C. (1987). Pragmatics and the grammar of anaphora: a partial pragmatic reduction of binding and control phenomena. Journal of Linguistics 23:379-434.

McCawley, J. D. (1978). Conversational implicature and the lexicon. In P. Cole, Ed., Syntax and Semantics 9: Pragmatics. New York: Academic Press, pp. 245-258.

Morgan, J. (1978). Two types of convention in indirect speech acts. In P. Cole, Ed., Syntax and Semantics 9: Pragmatics. New York: Academic Press, pp. 261-280.

Neale, S. (1992). Paul Grice and the philosophy of language. Linguistics and Philosophy 15:509-559.

Récanati, F. (1989). The pragmatics of what is said. In S. Davis, Ed., Pragmatics: A Reader. New York: Oxford University Press, pp. 97-120.

Sadock, J. M. (1978). On testing for conversational implicature. In P. Cole, Ed., Syntax and Semantics 9: Pragmatics. New York: Academic Press, pp. 281-298.

Walker, R. (1975). Conversational implicatures. In S. Blackburn, Ed., Meaning, Reference, and Necessity. Cambridge: Cambridge University Press, pp. 133-181.

Wilson, D., and D. Sperber. (1986). Inference and implicature. In S. Davis, Ed., Pragmatics: A Reader. New York: Oxford University Press, pp. 377-392.