Grice, "Implicatum conversationale"

IMPLICATUM CONVERSATIONALE -- conversational implicature: H. P. Grice’s term for a structure of implications based on features governing conversation and its context that supplements and at times overrides implications licensed by logic and the conventional meaning of terms. This notion is central to Grice’s influential theory of language. A person by saying a statement S implicates another statement T if he is aware that T is required to complete what he is saying and is also aware that his cooperative hearer s can normally work out the implied T from the spoken S according to certain principles governing a conversation. In this case, the conversation has an implicature, and T is the implicatum. One of the most important principles of conversational implicature is the cooperative principle, which states that you should “make your conversational contribution such as is required at the stage at which it occurs, by the accepted purpose or direction of the talk exchange in which you are engaged.” Conversational implicature is contrasted to conventional implicature, which is derived from the conventional meanings of the lexical terms occurring in the sentence and the sentential structure. “I wish to present a certain subclass of nonconventional implicatures, which I shall call conversational implicatures, as being essentially connected with certain features of discourse.” Grice, Studies in the Ways of Words.