The informativeness principle is an implicature in which the addressee is licensed to apply his or her knowledge of the world to infer an implicature that is informationally stronger than the actual utterance.
This principle, in addition to the cooperative principle and conversational maxims , enables the addressee to resolve apparent conflicts with the quantity maxim.
(English)
Levinson, Stephen C. 1983.Pragmatics. Cambridge, England: Cambridge University.