The aim of this article is to free Aristotle's Metaphysics, especially book XII (Lambda), frome some metaphysical and theological presuppositions by detecting their inappropriate conceptual framwork, which once was progressive, but now holds an obsolete position. Ousia, being (not substance, a much later concept, construed to solve other problems than Aristotle's), stand for a question, not for an answer. Book Lambda develops a highly speculative argument for this queston. The famous noesis noeseos says that empirical being and knowledge is the (...) realization of a noetic structure (noesis), laid down in our most fundamental opinioons about being. (shrink)