This paper extends the Dual-Layer Universe (Koku-Genki) model by proposing a third, deeper layer: the I-gen (異元), defined as the generative origin point within the Ma (間) domain. The I-gen is non-observable by definition — lying below the Planck scale — yet structurally necessary for the model's coherence, analogous to the role of imaginary numbers in mathematics. The paper argues that the I-gen corresponds structurally to the domain designated as divine (神仏の領域) across Shinto, Buddhist, Abrahamic, Taoist, and Neoplatonic traditions — not metaphorically, but structurally. This correspondence is an instance of Proof by Convergence (収束による証明): independent systems of inquiry converging on the same structural description of a non-observable generative origin.
Yoshimitsu Katayama (Thu,) studied this question.