H. P. Grice's Maxims for the "Cooperative Principle" of Communication
I. Quantity: 1. What you tell your reader should be as informative as your reader currently needs it to be. 2. What you tell your reader should not be more than your reader currently needs it to be.
II. Quality: Tell the truth. 1. Do not say things you believe to be false. 2. Do not say things for which you lack adequate evidence
III. Relation: Be relevant.
IV. Manner: Be perspicuous. 1. Avoid obscurity. 2. Avoid ambiguity. 3. Be brief. 4. Be orderly.
Paraphrased from "Logic and Conversation," in The Logic of Grammar, ed. Donald Davidson and Gilbert Harman (Encino, Cal.: Dickenson, 1975), pp. 64-75.
Grice, a philosopher of language, sought to establish by reasoning what fundamental rules are required to enable two users of any language to communicate. These "maxims" are, like any philosophical propositions, open to debate. Can you imagine cultures in which the reverse of any one of them would be required to communicate properly (e.g., "Do not tell the truth" or "Tell your reader more than s/he needs to know")? What happens to academic prose when each of these maxims is violated, and how can you tell from the way the prose sounds/feels/means that something specific has gone wrong? Do combinations of maxim-violations seem likely to occur under certain circumstances, especially for student writers?
If you are studying literary interpretation, or if your models for "good writing" come exclusively from literature, you probably already have realized that "literature" usually intentionally violates one or more of Grice's maxims. If nothing else, fiction is (technically, literally) a lie, so all novels are understood to violate the first maxim. When we read prose we identify as fiction, we find that violation entertaining and instructive, as when Huckleberry Finn warns us that his author, "Mr. Mark Twain," sometimes told "stretchers" now and then. When we read prose we identify as non-fiction and discover that it violates the first maxim, what happens? Do the same experiment for the other three maxims, and for specific examples of other genres of writing (e.g., lyric poems and song lyrics, drama, epic poems, jokes and fabliaux, romances). That will tell you much about the hidden conventions those genres' writers and readers assume in order to make the genres work. Imagine, for instance, someone who responded to a knock-knock joke's first exchange as if it were about to obey all four of Grice's maxims!