A Constraint-Based Framework for Ultimate Grounding (The Multi-Closure Thesis as a Structural Completion of the Dual-Closure Framework)

This paper develops a constraint-based extension of the Dual-Closure framework, which holds that authentic subjective experience and objective moral normativity jointly require non-contingent grounding in order to avoid justificatory regress. While the Dual-Closure Thesis establishes the necessity of such grounding, it leaves open the structural criteria any adequate ground must satisfy. This manuscript introduces the Multi-Closure Thesis, a conditional diagnostic framework consisting of five ontological and epistemic constraints. Rather than identifying or naming a specific metaphysical source, the framework delineates the minimal requirements any candidate ground must meet if it is to successfully terminate regress across consciousness, normativity, and rational agency. By applying these constraints—echoed in historical precedents such as Al-Ghazali and Maturidi—the paper demonstrates why contingent, consensus-based, and purely naturalistic accounts fail to achieve full closure. The result is not a doctrinal conclusion, but a narrowed ontological space within which any viable account of ultimate grounding must fall.