By Shankara Bharadwaj Khandavalli
There are four Upangas: Nyaya, Mimamsa, Itihasa-Purana and Dharma Sastra.
Nyaya is a darshana and speaks of the "law of nature". It also contains predicate logic.
Mimamsa is a darshana and has two parts - Purva Mimamsa and Uttara Mimamsa. Purva Mimamsa speaks of the philosophy of rituals and Uttara Mimamsa is spiritual philosophy. There is another text called Sankarsha kanda, which is also called the Madhya Mimamsa and Upasana Kanda, which speaks of Gods and mentions the essential one-ness of all God-forms. This can be seen as a ramp from Purva Mimamsa to Uttara Mimamsa. Mimamsa can be discussed more elaborately as a darshana.
There are 18 Maha Puranas and 18 Upa Puranas. Mahabharata is the Itihasa. The eighteen Maha Puranas are Matsya, Markandeya, Bhagavata, Bhavishya, Brahmanda, Brahma, Brahma Vaivarta, Vishnu Dharmottara, Varaha, Vamana, Siva, Skanda, Narada, Garuda, Padma, Kurma, Linga and Agni Puranas.
Purana is said to speak of five subjects (Panca Lakshana):
- the creation and dissolution of Universe,
- cycle of time,
- history of kings (human history)
They also speak of three levels of allegories - terrestrial, astronomical and spiritual.
They also speak of the different incarnations of the Supreme Godhead - 51 avataras, then 21 important ones from them, then 10 primary avatars out of them that we call as dashavataras and 2 as complete incarnations (purnavataras) which are Rama and Krishna. The remaining are said to be amshavataras (partial manifestation) in different degrees.
Dharma sastras include smritis and the four sutras - Dharma sutra, Grhya Sutra, Sulba Sutra and Srauta Sutra. The sutras are laid down for each Vedic sakha/branch.
- Dharma sutras contain the guidelines to live a Dharmic life.
- Grhya sutras contain specific guidelines to Grhasthas.
- Srauta sutras contain guidelines for performing rituals.
- Sulba sutras contain the mathematical principles for construction of various altars.