The paper deals with the problems related to the definition of aesthetic value. First, the definition of aesthetic value is approached from a methodological point of view (conceptual explication). Subsequently, a critical reconstruction of several traditional attempts at defining aesthetic value is carried on (I. Kant, M. C. Beardsley). These, due to their theoretical or epistemological assumptions, do not meet one of the criteria of a correct conceptual explication, i.e. the condition of similarity to ordinary language achieved by normative exclusion of certain aesthetic language games, including the heteronomy of aesthetic value. In the final part of the paper an attempt is made at defining aesthetic reaction and aesthetic property that could serve as a theoretical basis for aesthetic evaluation and taste researches in humanities and social sciences.