It has been my aim in this book to elaborate a rigorous ontological theory from Arnheim's writings for its ample benefits in understanding our contemporary medial situation, marked by unprecedented technological dependence and richness. Against the charge of those like Mitchell who argue that insisting on real medial difference "tends…to reduce that knowledge to a set of abstract propositions about the period aesthetic," I attempted to show in the preceding chapters the way in which a strong ontology of media form is necessary to understand completely – to characterize – the political-economic changes taking place.