[Contextual rationality and cognitive presupposition. An epistemological reflexion about Lombroso's case]

This article proposes an epistemological reflexion about the posture of the historian of human sciences towards his objects. Cesare Lombroso's theory of criminal anthropology was taken here as an example of the discussion because it seemed to be caricatural case. Considering that normative or whiggish perspectives cannot account for the logic of Lombroso's discourse, we attempt to develop here an alternative posture from which extrapolations could be made to other fields. This alternate is found in the introduction of the concepts of contextual rationality and cognitive presupposition and in a reconsideration of the time duration.