Is a speaker-based pragmatics possible? Or how can a hearer infer a speaker's commitment?

In this paper, the speaker's issue is tackled from an original point of view, that is, the semantic and pragmatic inferences utterances convey. It is claimed that two features allow drawing conclusions on the degree of the speaker's commitment: the strength of the inferences drawn from her utterance, and the accessibility to them. To insure a precise definition of the strength and the accessibility of inferences, truth-values are given for entailment, presupposition, explicature and implicature.