Uddalaka is teaching his son Shvetaketu, who has returned from twelve years of study convinced he knows a good deal. The father demolishes this in a few moves, then begins a series of demonstrations. He has salt dissolved in water and asks the boy to find it; it cannot be seen, and it is present throughout. He has a banyan seed split open and asks what is inside; nothing visible, and the tree comes from it. After each demonstration comes the same sentence: tat tvam asi, thou art That.
The sentence is a statement of identity, not a devotional flourish. Tat, That, refers to the subtle essence Uddalaka has just been pointing at, the thing that is not visible in the water or the seed and is nonetheless what everything is made of. Tvam is you. Asi is the verb to be, in its plain sense. The claim is not that you resemble the absolute, or are beloved of it, or are heading toward it. It is that the referent of the word you and the referent of the word That are one thing described from two positions.
It is repeated nine times, and the repetition is doing something specific. This is not information that becomes more true by being restated; it is a claim that the mind slides off, because everything in ordinary experience contradicts it. Vedanta later classified it as a mahavakya, a great statement, and specified how such a sentence should be handled: not accepted as a proposition but used as an instrument, through the removal of what it is not until the identity is no longer resisted.
Nine repetitions of one short sentence, because the difficulty was never in understanding the words. To see the other statements of the same order, explore more of The Living Sanatan Timeline.
Part 23 of 100 — Series II: To the Eternal
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