The idea of performativity of economics gave birth to several debates. The goal of this paper is to focus on a major caracteristic of this theory, that is the importance of technical dispositifs in the explication of the influence of economic theories on the social world. By this way, yhe sociology of performativity refuse to use classical sociological categories (convention, institution, social norm). We will focus on the roots of this epistemological precept, that is the actor network theory. Then, we will produce a critic of this posture by showing that technic dispositifs need to stand in a specific conventional background. We will conclude that it is contreproductive to ignore social background in the studies of performativity.