The aim of the paper is to outline the basic theoretical reasons for applying the concept of extended mind to literacy theory. In order to explicate theoretical difficulties faced by literacy theory, one needs to take into account the debate regarding technological determinism. Using this debate as an example, one can observe two basic strategies applied to defining the concept of a medium. On the one hand, there exists a strategy to formulate a narrow definition of a medium in terms (...) of material artifacts. On the other hand, one can observe a strategy which relies on creating a wide definition of a medium. According to this definition, a medium is understood as a social institution which denotes a particular way of behaving and thinking. The paper aims at justifying the hypothesis that both interpretational strategies employed in defining a medium and the related concept of technology are inaccurate in certain important respects. If the argumentation presented here proves correct, literacy theory will be faced with a serious dilemma: a choice between two equally unsuitable definitions of technology/media. However, the theoretical dilemma pertaining to the question of media can be elucidated by appealing to the conceptual framework of the extended mind hypothesis. (shrink)