Advaita Vedānta is a major nondual school of Vedānta, most famously systematized in the writings associated with Śaṅkara. Its central claim is that ultimate reality, Brahman, is nondual and that the deepest ātman is not truly separate from Brahman. Ordinary experience of independently existing selves and objects is analyzed through ignorance and mistaken superimposition rather than accepted as the final level of reality.
Texts such as Chāndogya Upaniṣad 6.8.7 are interpreted by Advaitins as central evidence, but other Vedānta schools read the same passages differently. Advaita does not mean that ethical behavior, ordinary suffering or practical responsibilities can simply be dismissed as “unreal.” Its theory distinguishes the standpoint of everyday transaction from ultimate insight. Its internal history also contains debates about how to understand ignorance, māyā and liberation.