It is only on the basis of assuming the relevance of b’s response that we can understand it as an answer to a’s question.

D). A number of different kinds of inference arise if we assume that the Maxim of Manner is being observed. The utterance The lone ranger rode into the sunset and jumped on his horse violates our expectation that events are recounted in the order in which they happen because the Maxim of Manner is flouted.

One more explanation of the fact why people are so often indirect in conveying what they mean was put forward by Geoffrey Leech in his book “Principles of Pragmatics”. He introduces the Politeness Principle which runs as follows: Minimize the expression of impolite beliefs; Maximize the expression of polite beliefs. According to G.Leech, the Politeness Principle is as valid as Cooperative Principle because it helps to explain why people do not always observe Maxims of Conversation. Quite often we are indirect in what we say because we want to minimize the expression of impoliteness:

A: Would you like to go to the theatre?

B: I have an exam tomorrow.

B is saying ‘no’, but indirectly, in order to be polite.