Paying more attention to the rhetorical side of argumentation raises epistemological questions. In this article I argue that rhetoric has to be an integral part of argumentative models if such models are to be considered rational. In other words, I claim that rhetoric is a necessary condition for argumentation studies. I am aware that this view may appear provocative. I hope to show that it is not the case, if we consider rationality to be a concept that encompasses more than (...) just a strictly logical way of thinking. Indeed, I would like to defend a humanistic conception of rationality as the background for a theory of rhetoric in order to underscore the specific rationality of the humanist frame of thinking for a .. (shrink)