 Pragmatics is usually thought to involve a different sort of reasoning than semantics. Semantics consists of conventional rules of meaning for expressions and their modes of combination. Locke supposed that communication was basically a matter of a speaker encoding thoughts into words and the listener decoding words back into thoughts. The same basic picture is found fairly explicitly in Saussure and other influential theorists. This picture seems to fit reasonably well with the picture that emerged from the logicians and philosophers of language in the tradition of logical analysis, of language as a system of phonological, syntactic and semantic rules, of which competent speakers and interpreters have implicit mastery. Paradigmatically, the sincere speaker plans to produce an utterance with the truth-conditions of a belief she wishes to express; she chooses her words so that her utterance has those truth-conditions; the credulous interpreter needs to perceive the utterance, and recognize which phones, morphemes, words and phrases are involved, and then using knowledge of the meanings, deduce the truth-conditions of the utterance and of the belief it expresses.