The purpose of this article is to expose the Work of Ignacio Espinosa, a liberal intellectual of the 19th Century, understood from three specific ways: its relationship with the intellectual group that determines him, the positivism that he promulgates, and the form that he builds his work, bound to some local mechanisms that facilitate the construction of knowledge. We will analyze the content of their more recognized works as positivists, without separating from this exercise, the way that these are product of a tradition and of some social factors that generate the credibility and the authorization to make statements and to speak on behalf of science.