The system of philosophy named after its founder, Carvaka, was set out in the Brhaspati Sutra in India probably about six hundred BCE. This text has not survived and, like similar philosophies in Greece, much of what we know of it comes from polemics against it and remarks by its critics.
One of the best sources for Carvakas atheistic argument happens to be a book, Sarvadarshansamgraha (the collection of all philosophies), written in the Fourteenth Century by Madhavacarya, a Vaishnavite (Hindhu) scholar