Integration by Constraints: How Divergent Traditions Can Share Epistemic Ground

Abstract: This essay makes explicit the method that governs the Return to Consciousness project: integration by constraints rather than by metaphysical commitments. Instead of asking which worldview is correct, constraint-based reasoning asks what any adequate account must explain — what conditions an explanation must satisfy regardless of its ontological commitments. The essay defines what constraints are, how they differ from beliefs, why they are discovered rather than chosen, and establishes four criteria for constraint-candidacy: robustness across methods, recurrence across contexts, resistance to eliminative explanation, and cost of exclusion. It distinguishes phenomenological regularities (constraint candidates) from metaphysical interpretations (not constraints) — a distinction the project relies on throughout. The central claim: constraint-based reasoning extends a strategy known from formal epistemology and political philosophy — agreement on conditions rather than conclusions — to metaphysical questions about consciousness, where the constraints include qualitative, first-person phenomena. The result is genuine pluralism without relativism: all frameworks subjected to the same discipline without being required to share assumptions. Keywords: constraint-based reasoning · epistemic integration · philosophical pluralism · phenomenological regularities · interdisciplinary methodology · tradition-bridging · metaphysical underdetermination Part of the Return to Consciousness research program — 26 philosophical essays exploring consciousness-first metaphysics. Full project: https://brunoton.github.io/return-to-consciousness/