The classification of Indian philosophical systems into Āstika and Nāstika is one of the most fundamental ways of understanding the diversity of classical Indian thought. The distinction does not primarily rest on theism versus atheism, as is often assumed, but rather on the acceptance or rejection of the epistemic authority of the Vedas. This criterion reflects the central role of sacred revelation in the intellectual history of India and provides a framework through which various schools articulate their metaphysical, epistemological, and ethical positions. Āstika Darśanas are those philosophical traditions that acknowledge the Vedas as a valid and authoritative source of knowledge. This acceptance does not imply uniformity of doctrine; rather, the Āstika systems display significant diversity in their metaphysical commitments. The six classical orthodox schools—Nyāya, Vaiśeṣika, Sāṃkhya, Yoga, Mīmāṃsā, and Vedānta—share reverence for Vedic authority but differ in their interpretations of reality, self, and liberation. For instance, Nyāya emphasizes logical analysis and epistemology, developing a sophisticated theory of inference and perception, while Vaiśeṣika focuses on an atomistic pluralism. Sāṃkhya proposes a dualism between