The Four Mahavakyas

The mahavakyas, the "great sayings", are four brief Upanishadic statements taken in Advaita Vedanta as expressing the identity of the individual self with Brahman. The selection of exactly four, one from each of the Vedas, is a later systematisation rather than an Upanishadic scheme, and it became standard in the Advaita tradition and in the initiation of renunciants in the Shankaracharya lineages, where a mahavakya is transmitted to the initiate.

Prajnanam Brahma, "consciousness is Brahman", from the Aitareya Upanishad (3.3) of the Rigveda. It is classified as the lakshana-vakya, the defining statement, since it says what the reality in question is.

Aham Brahmasmi, "I am Brahman", from the Brihadaranyaka Upanishad (1.4.10) of the Yajurveda. It is the anubhava-vakya, the statement of realisation, spoken in the first person by one who has understood.

Tat Tvam Asi, "you are that", from the Chandogya Upanishad (6.8.7 and repeated eight further times) of the Samaveda. It is the upadesha-vakya, the instruction given by teacher to pupil, and it occurs in the dialogue in which Uddalaka Aruni instructs his son Shvetaketu, driving the phrase home through a sequence of analogies: salt dissolved in water and still present throughout, the tiny seed from which the great banyan grows, rivers that lose their names in the sea.

Ayam Atma Brahma, "this self is Brahman", from the Mandukya Upanishad (2) of the Atharvaveda. It is the abhijna-vakya, the statement of recognition.

The four are read differently by the Vedanta schools, and those differences are the schools' whole disagreement in miniature. Advaita reads tat tvam asi as a straightforward identity, and Shankara devotes close analysis to explaining how two terms whose apparent references are incompatible can share a referent once the incompatible connotations are set aside, the individual's limitation and the supreme's remoteness both dropping away. Ramanuja reads the sentence as asserting that Brahman is the inner self of whatever "you" denotes, so that it states inseparability and dependence rather than identity. Madhva reads it on a different division of the Sanskrit as atat tvam asi, "you are not that", so that the sentence asserts difference. Whether that reading is grammatically defensible has been argued over ever since, and the exchange is one of the sharper examples of how much can turn on how a continuous Sanskrit text is divided.

The count of exactly four mahavakyas is itself a later fact, not an Upanishadic one. The Upanishads contain many sentences asserting identity between self and Brahman; the selection of one per Veda and the label mahavakya for that set belongs to the systematising phase of Advaita after Shankara. The Vakya-vritti, a short verse commentary traditionally attributed to Shankara though its authorship is debated by scholars, is among the texts that fixed the set and its reading for later students.

The four sayings then acquired an institutional life beyond exegesis. The monastic orders founded in the Shankara lineage trace themselves to principal mathas, and tradition ties each matha to a Veda and, through it, to a mahavakya, so that a renunciant's initiation links him to a specific text and a specific monastic house at once. Accounts of exactly which matha holds which mahavakya differ in the sources, which is itself evidence that the scheme hardened gradually rather than arriving whole.

Outside Advaita monasticism, the mahavakyas took on a second career in the nineteenth and twentieth centuries as exhibits in a more universalist Hindu apologetic addressed to the West. Popular addresses have quoted tat tvam asi as a summary ethical claim, that the same reality is present in every being, rather than as the technical identity statement Shankara argued for at length against rival readings. That popular gloss is widely repeated and is not the reading the Advaita commentarial tradition itself defends; it belongs to a later, outward-facing presentation of Vedanta more than to the classroom transmission described in the first article.