Bṛhaspati: the founder of Cārvāka or Lokāyata philosophy: The lost Bārhaspatya-sūtras

Bṛhaspati is sometimes referred to as the founder of Cārvāka or Lokāyata philosophy. The earliest direct quote from Bṛhaspati's lost writings is found in the text Sarvasiddhantasamgraha, which is sometimes controversially attributed to Adi Shankara. In theSarvasiddhantasamgraha, the author quotes Brihaspati as follows:

Chastity and other such ordinances are laid down by clever weaklings; gifts of gold and land, the pleasure of invitations to dinner, are devised by indigent people with stomachs lean with hunger.
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The building of temples, houses for water-supply, tanks, wells, resting places, and the like, please only travelers, not others.
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The Agnihotra ritual, the three Vedas, the triple staff, the ash-smearing, are the ways of gaining a livelihood for those who are lacking in intellect and energy.
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The wise should enjoy the pleasures of this world through the more appropriate available means of agriculture, tending cattle, trade, political administration, etc.

Bṛhaspati (Sanskrit: बृहस्पति, "lord of prayer or devotion",^[1] often written as Brihaspati or Bruhaspati) also known as Deva-guru(guru of the gods), is a Hindu god and a Vedic deity. He is considered the personification of piety and religion, and the chief 'offerer of prayers and sacrifices to the gods' (Sanskrit: Purohita), with whom he intercedes on behalf of humankind.

He is the guru of the Devas (gods) and the nemesis of Shukracharya, the guru of the Danavas (demons). He is also known as Ganapati (leader of the group [of planets]), and Guru (teacher), the god of wisdom and eloquence, to whom various works are ascribed, such as the Barhaspatya sutras.

He is described as of yellow or golden color and holding the following divine attributes: a stick, a lotus and beads. He presides over 'Guru-var' or Thursday.^[2]

In astrology, Bṛhaspati is the regent of Jupiter and is often identified with the planet.

The Bārhaspatya-sūtras (a patronymic of Brhaspati), also Lokāyata ("materialistic", "atheistic") sutras were the foundational text of the Cārvākaschool of "materialist" (nastika) philosophy.

Probably dating to the final centuries BC (the Mauryan period), these texts have been lost, and are known only from fragmentary quotations. Dakshinaranjan Shastri in 1928 published 60 such verses. In 1959, he published 54 selected verses as Barhaspatya sutram. Shastri was of the opinion that many more fragments could be recovered. Bhattacharya (2002) attempts a new reconstruction, with the caveat that the more verses are listed, the greater the uncertainty that it will be either misquoted or foreign materials included as a part of the text.

Most of the fragments are found in works dated to the Indian Middle Ages, between roughly the 8th and 12th centuries. The extensive 14th century treatise on Indian philosophy by Sayana, the Sarvadarshanasamgraha, gives a detailed account of Cārvāka, but it doesn't quote Cārvāka texts directly, instead paraphrasing the doctrine according to the understanding of a learned 14th century Vedantin. Bhattacharya lists 68 items on 9 pages.