This term is an established theological term within Hindu philosophy which denotes a specific line of theological development within a Hindu religious tradition. The traditional schools of Hindu philosophy have had their siddhantas established by their respective founders in the form of Sutras (aphorisms). The Sutras are commented by a major philosopher in the respective traditions to elaborate upon the established doctrine by quoting from the shastras (scriptures) and using logic and pramanas (accepted source of knowledge). For example, in the tradition of Vedanta, the author of the Sutra was Veda Vyasa and the commentators were Adi Shankara, Ramanuja and Madhva (each of whom eventually set up sub-schools within Vedanta). Also, in the tradition of Purva Mimamsa, the author of the Sutra wa