Chapter 88: The CI as j-Closed Fixed Point

The centrepiece of the ethics expansion. The categorical imperative is not postulated but derived: it is the minimal j-closed fixed point in the presheaf topos over the site of rational perspectives. The CI structure — maxim space, universalization endofunctor, coherence test, respect operator — forms a typed operator graph that is stable under the dignity modality j_dig. Any weaker structure fails j-closure; any stronger structure is redundant. This gives uniqueness up to natural isomorphism and establishes that the CI already lives in the admissible subworld.