Uddālaka Āruṇi

Uddālaka Āruṇi is a renowned sage of the Upanishadic period and the teacher of the famous mahāvākya (great saying) “Tat tvam asi” (That thou art). He appears as the father and teacher of Shvetaketu in the Chāndogya Upaniṣad.

Life/History

Uddālaka Āruṇi is mentioned in several Upanishads and Brahmanas as a learned teacher of Vedāntic wisdom. In the Chāndogya Upaniṣad, he instructs his son Shvetaketu after the young man returns home from his Vedic studies without having understood the ultimate truth. Uddālaka uses everyday examples—salt in water, rivers flowing into the ocean, sleep and waking—to point to the non-dual nature of reality.

Teachings/Contributions

Uddālaka Āruṇi’s most famous teaching is the mahāvākya “Tat tvam asi” (You are That), which appears nine times in the sixth chapter of the Chāndogya Upaniṣad. He teaches that the Self (ātman) and Brahman are one, using the examples of the invisible essence in rivers, the unseen principle in sleep, and the unseen essence in gold, earth, and space to illustrate the identity of the individual and universal Self.

Legacy

Uddālaka Āruṇi is considered one of the most important teachers of Vedānta. His method of teaching through examples from everyday life became a model for later Upanishadic instruction. The mahāvākya “Tat tvam asi” is one of the four great sayings of the Upanishads and is central to Advaita Vedānta philosophy. He is also mentioned in the Bṛhadāraṇyaka Upaniṣad and other texts.

Verification notes

• Content based on client-provided research.
• Audited against Wikipedia (September 2026). Dating is traditional/uncertain (Wikipedia: fl. c. 8th century BCE, a few centuries before the Buddha).