The aim of this paper is to define a methodology that clarifies some crucial aspects of scientific representative practices. By investigating symmetry as a case study, this method explores the use of models and relates it to specific practical functions. In the first section, I emphasize the fruitfulness of a philosophical enquiry that accounts for the aims and the objectives towards which scientific practices direct their interest. Secondly, by using symmetry as a case study, I try to show that philosophy can find rich pathways of interaction with sciences, by proposing a dynamical approach to scientific representation. In the third section of the paper, I shall refer to examples that highlight the use of symmetry in current scientific representative practices. I shall conclude with some remarks on this method and its epistemological implications on our conception of objectivity and symmetry.