Claim. Kant’s doctrine that the thing-in-itself (noumenal reality) is unknowable fails because, in Unification Thought, the thing-in-itself is the Sungsang of an object and the sense content is its Hyungsang — and since Sungsang is always expressed through Hyungsang in created beings, we can in fact know the Sungsang through the Hyungsang.
Elaboration. Lee identifies Kant’s separation of phenomenal reality from noumenal reality as the root of multiple downstream separations: ‘This led to the separation between pure reason and practical reason, and between science and religion’ (Critique of Kantian Agnosticism). The Unification critique attacks the underlying dichotomy: ‘the thing-in-itself is the Sungsang of a thing, while the sense content is its Hyungsang. Sungsang and Hyungsang are unified in all things, and since Sungsang is expressed through Hyungsang, we can know the Sungsang of a thing through its Hyungsang.’
The diagnostic is that Kant lacked two key pieces. First, he did not see the principled created relationship between humans and all things — the microcosm thesis that makes the subject’s content/form correspond to the object’s content/form. Second, he did not see that the human being is the united being of spirit self and physical self, which means cognition itself has both phenomenal and noumenal access. Lee writes: ‘Since Kant was not aware of the principled relationship between humans and all things, nor of the fact that a human being is the united being of spirit self and physical self, he could stray into agnosticism.’
The argument has both a metaphysical and an anthropological prong. Metaphysically: created beings have dual-characteristics — Sungsang and Hyungsang are inseparable, with Sungsang expressed through Hyungsang. So the Hyungsang (sense content) is not a veil over the Sungsang (thing-in-itself) but its expression. Anthropologically: the cognizing human has both a spirit self (which can engage Sungsang) and a physical self (which engages Hyungsang) — so the bifurcated reality is matched by a bifurcated cognizer.
Lee further argues that things were created in resemblance to the human as ‘objects of joy,’ so subject and object resemble each other in content AND form — making collation possible at both Sungsang and Hyungsang levels. The anti-agnostic claim is strong: ‘the subject can cognize not only the Hyungsang (sense content and sense form) of the object, but also its Sungsang (the thing-in-itself).’
This is a claim worth a serious thread. Kant’s argument for the unknowability of the thing-in-itself rests on the constructive role of the categories — even if there’s an isomorphism between subject and object, that isomorphism would still be perspectival. Lee’s reply implicitly is that the isomorphism is non-perspectival because it is designed (by the same Creator who designed both). Critics from Kantian and post-Kantian traditions typically engage on whether ‘designed correspondence’ actually escapes the perspectival worry or merely pushes it back a step.
See also. kants-transcendental-logic-a-priori-forms, ut-critique-of-marxist-reflection-theory-requires-interest-and-prototype, sungsang-and-hyungsang-as-dual-characteristics-of-god