Abstract

Contemporary epistemology is fragmented across competing traditions - scientific realism, structural realism, constructive empiricism, social epistemology, and practice-based approaches - each capturing genuine insights while dismissing rivals. I propose Operational Constraint Theory (OCT) as a unifying framework for empirical and formal knowledge. Its central thesis is that knowledge is the mapping of constraint structures through operations that reveal invariances. OCT synthesizes insights from multiple traditions: realism’s recognition that inquiry meets resistance; structural realism’s insight that relational patterns persist through theory change; constructive empiricism’s emphasis on operational mediation; social epistemology’s recognition that knowledge is collectively constituted; and practice-based approaches’ insight that knowing is doing. The framework offers four innovations that address lacunae in existing approaches: 1. Factor-based operational independence criteria for assessing when convergence is evidentially significant. 2. The genuine/spurious invariance distinction, which provides diagnostic tools for phenomena such as the replication crisis. 3. A constraint network model that replaces rigid hierarchies and accommodates bidirectional constraints. 4. Non-circular progress criteria that avoid defining progress as convergence toward truth. The article positions OCT through methodological structuralism - a commitment to the structure-reality of constraints grounded in operational convergence rather than metaphysical assertion - and demonstrates its applicability through case studies spanning the Newton-Einstein transition, the replication crisis in psychology, the BICEP2 episode, and quantum mechanics. Four open problems are acknowledged: scope limitation to descriptive knowledge, testability, self-application circularity, and theory-ladenness. OCT is offered as a research program meriting critical engagement, not as a finished theory.