The metaphysics resulting from this epistemology is that the socalled thing in itself is not a cause of our sensations, but a product of one's own thinking, a determination of the Ego, a thing known to the Ego which constructs it.
Kant, however, had no epistemology for such a contention, because according to him both outer and inner senses give mere appearance, from which we could not know either body in itself, or soul in itself.
Tried to effect a harmony of Kant and Hegel by proceeding from the epistemology of the former to the metaphysics of the latter.
This introduces us to the second part of the question we are seeking to determine, namely the relation of epistemology to metaphysics.
The three most vital idealisms of this kind at the moment are the panpneumatism of Hartmann, combining Hegel with Schopenhauer; the panteleologism of Lotze, reviving Leibnitz; and the panpsychism of Paulsen, continuing Fechner, but with the addition of an epistemology combining Kant with Schopenhauer.
Without prejudice, then, to the claim of epistemology to constitute the central philosophic discipline, we may simply note its liability to be pressed too far.
The result of the foregoing, however, is to show that, as soon as epistemology draws its conclusion, it becomes metaphysics; the theory of knowledge passes into a theory of being.
Some thinkers have identified the two, while others regard Epistemology as a subdivision of logic; others demarcate their relative spheres by confining logic to the science of the laws of thought, i.e.
We, on the contrary, mainly through the influence of Descartes, rather ask what are the things we know, and therefore, some more and some less, come to connect ontology with epistemology, and in consequence come to treat metaphysics in relation to psychology and logic, from which epistemology is an offshoot.
If self-consciousness be treated in this objective fashion, then we pass naturally from epistemology to metaphysics or ontology.