In the contemporary philosophy of science, the champions of the realist–empiricist dispute are structural realism and constructive empiricism, respectively. In establishing their historical lineage, structural realists point to the work of Ernst Cassirer. In this dissertation, I argue that Cassirer cannot be pressed into service to their cause; while some of his conclusions about science seem prima facie in line with structure realism, any such agreement is merely apparent. Digging into Cassirer’s philosophy of science, and situating that work within his broader project of the philosophy of symbolic forms, it becomes clear that his arguments instead present an important challenge to the structural realist camp. In fact, his arguments against abstraction and epistemic foundationalism speak against any assumption of a mind-independent world, undermining the contemporary realist–empiricist dispute in toto. In place of the doctrines of realism and empiricism, Cassirer offers us the system of the symbolic forms. In place of the empirical and metaphysical stances, I develop on Cassirer’s behalf the critical stance, drawing on Cassirer’s appreciation of Kantian transcendentalism and Hegelian dialecticism.