conceptual

  In “presupposition and conversational implicature”, Grice is interested in the question of whether what Strawson called “presupposition” was something that could be accounted for in terms of conversational implicature or some similar   (what we would now call) pragmatic mechanism. He considers several examples, but cares mostly about the existential presupposition of (utterances of sentences containing) definite descriptions, factives and what Robert Stainton and myself have called “Quasi-factives”, i.e., sentences like: Peter does not regret inviting Joanna to the party. which, when asserted, defeasibly but strongly imply the truth of their complement (in this case, that Peter invited Joanna to the party). According to Grice, the existential presupposition of definite descriptions can be easily accounted for by appealing to a norm of manner according to which it is bad manners to hide the main point of your assertion (my phrasing, not his). This is what he calls the principle of con