Whereas this idea has been analyzed primarily in view of its philosophical sources, this paper is supposed to clarify its internal logic. The main feature of Augustine's concept is the distinction between the two projects of a critique of reason and of a metaphysics, and the coordination of these projects within a treatise on theodicy. Augustine systematizes the disciplinae in the perspective of reason's self-recognition.
Reason manifests itself in culture and nature.
Through the sciences, reason is led to a reflection upon its own products and, finally, to an understanding of them as reason's self-manifestations. Thus, reason becomes able to comprehend itself. The second group helps carry out a metaphysical ascent from the material to the intelligible world. In philosophy, reason comprehends its ability to constitute knowledge as a synthetic capacity that points to a transnumerical unity as the main ontological feature of the intelligible world. The insight into this kind of unity reveals the meaningful interwovenness of all beings and events and, thus, leads to a refutation of all objections against divine providence.