Great philosophical works are neither descriptions nor evaluations, but rather interpretations of "the world", or, to be more precise, of the objects of a more or less extended parcel of our thought. Hermeneutic products such as philosophical systems are neither true nor false, neither valid nor invalid in a straightforward sense. It would be less misleading to apply to them such categories as "rich" and "profound", or "poor" and "trivial", in a way similar (thought not identical, of course) to the application of these categories to a work of art.