If we therefore define philosophy as a whole according to that wherein it surveys and presents everything, namely the absolute act of cognition, of which even Nature is again only one side, the Idea of all ideas, then it is Idealism. Idealism is and remains, therefore, the whole of philosophy, and only under itself does the latter again comprehend idealism and realism, save that the first absolute Idealism is not to be confused with this other, which is of a merely relative kind. (IP 50; SW 1, 1