Abstract : The public: definitions and perceptions The public is a difficult concept to grasp. It exhibits contradictory meanings: a collective abstract entity that is based on a “togetherness” founded on the exercise of reason; a cumulative heterogeneous phenomenon formed into an audience by certain kinds of specialised proceedings; or, another possibility, the driving force of action aimed at modifying something of the individuals that one wishes to reach. In all these cases, it is not a self-defined social collective. However, we constantly speak of the public's point of view. Can we really contemplate a situation in which the public could be thought of as a potential enunciator of a point of view? Or at least as an interlocutor in communication with the institutions of which it is the public? This article describes the division between the status of the members of the public engaged in interpersonal communications with representatives of the institution and the status of the public as a collective abstract entity engaged in a “communication” with the institution.