Upanishadic people

Yajnavalkya or Yagyavalkya (, IAST:) is a Hindu Vedic sage prominently mentioned in the Brihadaranyaka Upanishad (c. 700 BCE) and Tattiriya Upanishad. Yajnavalkya proposes and debates metaphysical questions about the nature of existence, consciousness and impermanence, and expounds the epistemic doctrine of neti neti ("not this, not this") to discover the universal Self and Ātman. Texts attributed to him include the Yajnavalkya Smriti, Yoga Yajnavalkya and some texts of the Vedanta school. He is also mentioned in the Mahabharata as well as various Puranas, Brahmanas and Aranyakas.

ancient Indian philosopher

Maitreyi (fl. 8th century BCE) was an Indian philosopher who lived during the later Vedic period in ancient India. She is mentioned in the Brihadaranyaka Upanishad as one of two wives of the Vedic sage Yajnavalkya. In the Hindu epic Mahabharata and the Gṛhyasūtras, however, Maitreyi is described as an Advaita philosopher who never married. In ancient Sanskrit literature, she is known as a brahmavadini (an expounder of the Veda).

Nachiketas (), also rendered Nachiketā and Nachiketan, is a character in Hindu literature. He is the son of the sage Vājashravas, or Uddalaki, in some traditions. He is the child protagonist of an ancient Indian dialogical narrative about the nature of the atman (soul).

Pippalada () was a sage and philosopher in Hindu tradition. He is best known for being attributed the authorship of the Prashna Upanishad, which is among the ten Mukhya Upanishads. He is believed to have founded the Pippalada school of thought, which taught the Atharvaveda. He is regarded to be an incarnation (āṃśa) of Shiva in some Puranas.

Vedic sage born to an unwed mother

Svetaketu (), also spelt Shvetaketu, was a sage mentioned in the Chandogya Upanishad. He was the son of the sage Uddalaka, and represents the pursuit of knowledge.