Four-Level Self-Referential Closur:A Carrier-Independent Paradigm of Cognitive Ontology

Contemporary theories of consciousness and metacognition, including Higher-Order Thought theory (HOT), Global Neuronal Workspace Theory (GNWT), Integrated Information Theory (IIT), and active inference frameworks, are mostly anchored to carbon-based biological carriers. This paper proposes a carrier-independent hierarchical framework built upon nested self-referential closures, which divides cognitive structures into four sequentially recursive topological levels: first-order self-referential closure corresponds to phenomenal consciousness, second-order self-referential closure to selfhood, third-order self-referential closure to metacognition, and fourth-order self-referential closure to metacognitive axiomatization. Taking self-referential closure as the generative backbone of cognition, this framework is compatible with observational findings from Western cognitive science on the one hand, and establishes structured phenomenological correspondence with introspective traditions of Eastern thought on the other. Treating cognitive structures as topological invariants, it suspends the presupposition that consciousness is necessarily bound to biological substrates. It furnishes a neutral descriptive language for cross-carrier cognitive comparison and carbonsilicon cognitive alignment, and supplies a unified interpretive criterion for resolving divergences among competing AGI paradigms. This paper only renders phenomenological and ontological mapping of cognitive forms, without specifying dynamical operational pathways or engineering implementations for such structures on any carrier.