Tat tvam asi

Tat Tvam Asi (Devanagari: तत्त्वमसि), a Sanskrit phrase, translated variously as "Thou art that," (That thou art, That art thou, You are that, or That you are, or You're it) is one of the Mahāvākyas (Grand Pronouncements) in Vedantic Sanatana Dharma. It originally occurs in the Chandogya Upanishad 6.8.7, in the dialogue between Uddalaka 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. The meaning of this saying is that the Self - in its original, pure, primordial state - is wholly or partially identifiable or identical with the Ultimate Reality that is the ground and origin of all phenomena.

Major Vedantic schools offer different interpretations of the phrase:

Tat tvam asi is the Mahāvākya (Grand Pronouncement) from Chandogya Upanishad. The Advaita school of Shankara assigns a fundamental importance to this Mahāvākya and three others of the same kind from three other Upanishads.

The Vedas form the fundamental source text for everything in Hinduism. Each of the four Vedas has metaphysical speculations, known as Upanishads, at the end. Among the various discussions in these Upanishads there are mahavakyas (Grand pronouncements), which are of foundational import and deep significance. Tat tvam asi (meaning, That Thou Art) is one such. This is from Chandogya Upanishad. Different schools of philosophy interpret such fundamental statements in significantly different ways, so as to be consistent with their own philosophical thought. Below is the interpretation of the Vishishtadvaita school.

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