Gargi Vachaknavi was an ancient Indian philosopher. In Vedic Literature, she is honored as one of the great natural philosophers. She is mentioned in the Sixth and the Eighth Brahmana of Brihadaranyaka Upanishad, where the brahmayajna, a philosophic congress organized by King Janaka of Videha is described, she challenged the sage Yajnavalkya with intriguing questions on the atman (soul).Gargi was named after the sage Garga, in whose lineage she was born; her last name comes from her father Vachaknu.Gargi composed several hymns that questioned the origin of all existence. The Yoga Yajnavalkya, a classical text on Yoga is a dialogue between Gargi and sage Yajnavalkya. Gargi was one of the Navaratnas in the court of King Janaka of Mithila. She has composed several hymns and is an author of Gargi Samhita.