Who they are

Uddalaka Aruni is the Upanishads' great teacher by way of ordinary things. Where other figures reach for paradox, he reaches for a lump of salt, a fig seed, a tree cut into, rivers running to the sea, a man led blindfolded into strange country. The sixth chapter of the Chandogya is essentially his, and its argument is carried almost entirely by objects a farmer would recognise. That is a deliberate pedagogy, not a limitation: he is teaching a son who has just spent twelve years with books, and the correction he administers is that the thing worth knowing was never in the books.

His name marks his father. Aruni means son of Aruna, and he appears across the older literature as Uddalaka Aruni or Aruni Gautama — enough of a fixed point that later texts use him as a marker for a whole period of teaching.

The detail that makes him more interesting than a wise father, though, is that this Upanishadic heavyweight is repeatedly shown as a student, and shown losing. When his son comes home humiliated from the court of the king Pravahana Jaivali, unable to answer five questions about where the dead go and how they come back, Uddalaka finds he cannot answer them either. So he goes to the king himself and asks to be taught — a Brahmin going as a pupil to a kshatriya, which both the Chandogya and the Brihadaranyaka record without embarrassment, and which the king himself remarks on. Later, at Janaka's assembly, Uddalaka takes his turn questioning Yajnavalkya and is answered and sits down like the rest.

So the man who tells his son that twelve years of study missed the essential thing has been on the receiving end of exactly that lesson, more than once, and the texts keep the record. It gives his teaching a particular authority. He is not correcting Svetaketu from above; he is correcting him from having been there.

His actual argument in Chandogya 6 is more systematic than the famous line suggests. He begins with a claim about how things come to be at all — that in the beginning there was Being, one only, without a second — and works from there to the conclusion that the subtle essence pervading everything is what a person most is. Then he says it nine times, after nine different images, because he evidently does not expect it to land the first time. The repetition is the teaching method showing its own workings.

What he is remembered for is the sentence at the end of each of those nine passes: that subtle essence is the Self, and thou art that — tat tvam asi, one of the great statements later Vedanta built on. What is easy to miss is that he never asks Svetaketu to accept it. He builds the ground under it nine separate times and lets the boy walk up to it himself.

Key dialogues

• Tat Tvam Asi — the Salt in Water

Questions to explore

• Why does Uddalaka use salt dissolved in water to teach the Self?
• What is Uddalaka correcting in Svetaketu's book-learning?