The reflection on the preconditions and evolution of science has played a decisive role in the development of Ernst Cassirer's philosophy, contributing to its functional and thus inherently pluralistic and holistic view of knowledge. To present Cassirer's conception of physics as an open symbolic formation enables us to reveal and study the radical features of his epistemological model: (1) the fundamental process of generating sense-units and meaning in its constitutive character for each attempt of objectification, (2) its driving and structuring (...) dynamics that touches and transforms all elements of knowledge, the a priori included, (3) the strategies of justification that allow maintaining the claim of truthfulness in spite the fact that Cassirer's open model integrates contingency and transitoriness as an inherent part of knowledge. It thus becomes clear that Cassirer's term 'symbol' cannot be reduced to its habitual representational acceptation, for its key theoretical function is to overcome the inconsistencies of dualistic epistemological models. It is this re-orientation, a kind of 'second Copernican revolution', that allows Cassirer to go beyond traditional dichotomies and to propose a larger frame in which to appreciate the diversity of human understanding. (shrink)