This article focuses on the problem of the categorization of the adverb sans doute as an epistemico-modal marker or an evidential marker. Starting from a critical appraisal of an analysis proposed by Bourmayan et Ashino, in which sans doute is considered fundamentally epistemico-modal, three hypotheses are presented, which depart from theirs. First, sans doute has as its main lexical element an inferential evidential value: it signals that the content qualified by the adverb is the result of a defeasible type of inference from clues/premises. Second, due to the defeasibility of the inference, the statement containing the adverb takes on, invariably, a pragmatic value of non-certainty, not lexically coded, however. Sans doute is thus not an epistemico-modal marker by itself in contemporary French. Third, the adverb combines these values with an epistemic value of what we call “posture of certainty”. Different from epistemic modality, which refers to an evaluation in terms of certainty, and/or to the epistemic cognitive state linked to that, posture of certainty refers to what can be called the tone or epistemic behavior of confidence the speaker shows. Sans doute therefore indicates without contradiction, a defeasible and, thus, uncertain hypothesis, presented with a tone of full confidence.