 Nāgārjuna’s theory of the two truths is fundamentally different from all theories of truth in other Indian philosophies. Hindu philosophers of the Nyāya-Vaiśeṣika, Sāṃkya-Yoga, and Mīmāṁsā-Vedānta—all advocate a foundationalism of some kind according to which ultimate reality is taken to be “substantive reality” (drayva) or foundation upon which stands the entire edifice of the conventional ontological structures where the ultimate reality is posited as immutable, fixed, irreducible and independent of any interpretative conventions. That is so, even though the conventional structure that stands upon it constantly changes and transforms.