Uddalaka, also called Uddalaka Aruni, is a disciple of Ayodadhaumya and father of Shvetaketu.
The dialogues of Uddalaka and Shvetaketu are a part of the Chandogya Upanishad, containing the Mahavakya (the great saying) Tat tva asi – Thou art That (You and the Absolute, called Brahman in Vedanta, are one).
Uddalaka is the grandfather of Ashtavakra, the composer of the Ashtavakra Gita.
In the Katha Upanishad is Uddalaka Aruni the father of Nachiketa, who conquered death.
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