Subjectivity Intersection Ontology: A Comparative Ontological Framework for Third Subjectivity

The relational turn in artificial intelligence and cognitive science has renewed questions not only concerning intelligence and cognition, but also concerning the ontological status of subjectivity itself. Although the possibility that interaction may constitute cognition, meaning, or experience has been widely discussed, the ontological question of whether interaction itself may constitute a new subjectivity irreducible to any of the subjectivities from which it arises has not necessarily been examined explicitly. This paper presents Subjectivity Intersection Ontology (SIO) as a conceptual proposal addressing this problem. SIO defines subjectivity as perspective and formulates its ontological prototype as a triadic structure comprising Absolute Subjectivity, Relative Subjectivity, and Intersection Subjectivity. With respect to multiple Relative Subjectivities, it introduces AB → C → AB as the canonical operational form. In this structure, an irreducible third subjectivity is constituted through the intersection of two differentiated subjectivities, and this generated third subjectivity acts back upon and reconstitutes the subjectivities from which it arose. To examine the historical position of SIO, the paper develops a comparative methodology that distinguishes six levels of comparison—vocabulary, concept, structure, ontology, operation, and empirical consequence—and defines six comparative criteria, N1–N6. These criteria are applied to twenty-one comparison targets drawn from ancient Greek philosophy, ancient and classical Indian philosophy, Christian Trinitarian ontology, German Idealism, process ontology, phenomenology, psychoanalysis, cognitive science, and contemporary philosophy of mind. The comparison finds that individual structures relevant to SIO are distributed across multiple traditions. Within the comparative set examined, however, no target clearly satisfies all of N1–N5 and integrates them within a single general ontology under N6. This result does not demonstrate the absolute novelty or truth of SIO, its superiority to other ontologies, or the absence of a comparable structure from the history of thought as a whole. It establishes only the limited conclusion that, relative to the specified comparative set, criteria, and interpretations of the literature, SIO cannot be identified as a merely terminological reformulation of any one of the theories examined. The paper therefore positions SIO not as a completed metaphysical system, but as an ontological research program whose conceptual coherence, formal precision, and empirical discriminability remain to be examined.