Tat Tvam Asi, a sanskrit sentence, translating variously to "thusness", "Thou art that", "That thou art", or "You are that", is one of the four Mahāvākyas (Grand Pronouncements) in Hinduism. It originally occurs in the Chandogya Upanishad. It first occurs in Chandogya 6.8.7, in the dialogue between Uddālaka and his son Śvetaketu; it appears at the end of a section, and is repeated at the end of the subsequent sections as a refrain. It is generally taken to mean that your soul or consciousness is wholly or partially the Ultimate Reality. That is to say, even before the creation of the universe, a unitary, divine consciousness existed, and that this consciousness is identical to your deepest self.

The deep interpretation of this for Hindu philosophy is seen differently by the three major schools of Indian philosophy. The masters

• The Advaita interpretation holds that the essentials of 'tat' (That Supreme, which is called Brahman) and 'tvam' (this individual you) are exactly the same. See Tat tvam asi: advaita interpretation.
• The Vishishtadvaita interpretation holds that this individual soul is a part of the whole which is 'tat'. See Tat tvam asi: vishishtadvaita interpretation.
• The Dvaita interpretation holds that it is actually 'atat tvam asi', which means You are not that. See Tat tvam asi: dvaita interpretation.

The other three Mahāvākyas are:

• Prajnānam Brahma -- Consciousness is Brahman. (Rig Veda : Aitareya Upanishad);
• Aham Brahma asmi -- I am Brahman. (Yajur Veda: Brihadaranyaka Upanishad);
• Ayam ĀtmĀ Brahma -- This Atman is Brahman. (Atharva Veda: Mandukya Upanishad)

See also

• Thou Art God
• Jiva