Ontological Invariance and Contextual Cognition: Nyāya Epistemology and Empirical Violations of Classical Probability

Empirical research in cognitive science has documented systematic departures from classical probability theory in human judgment, including conjunction fallacies and order effects. Because classical probability is defined over a Boolean algebra of events, such findings have motivated non-Boolean modeling frameworks, including quantum probabilistic approaches to cognition. This paper examines the implications of these developments for Nyāya epistemology. Drawing on the Nyāya Sūtra and its classical and Navya-Nyāya commentaries, we reconstruct the theory of vyāpti (pervasion) as grounding inference (anumāna) in invariant relations between properties rather than in numerical coherence among belief states. We argue that empirical violations of classical probability concern the structure of cognitive representation, whereas Nyāya’s account of inference operates at the level of ontological relations and categorical epistemic warrant. Although both Nyāya and contemporary non-classical cognitive models acknowledge the role of contextual constraints, they theorize contextuality differently: quantum approaches embed it within representational algebra, whereas Nyāya treats it as an epistemic limitation to be resolved through domain refinement. The comparison clarifies the distinct explanatory strata involved and contributes to broader debates concerning rationality, contextuality, and the normative status of probability.