Prasthanatrayi
# Prasthanatrayi

Prasthanatrayi (Sanskrit: प्रस्थानत्रयी, IAST: Prasthānatrayī), literally, three sources (or axioms), refers to the three canonical texts of theology having epistemic authority, especially of the Vedanta schools. It consists of:

* The Upanishads, known as Upadeśa Prasthāna (injunctive texts), and the Śruti Prasthāna (the starting point or axiom of revelation), especially the Principal Upanishads.
* The Bhagavad Gita, known as Sādhana Prasthāna (practical text), and the Smṛti Prasthāna (the starting point or axiom of remembered tradition)
* The Brahma Sutras, known as Sūtra Prasthāna (formulative texts) or Nyāya Prasthāna or Yukti Prasthāna (logical text or axiom of logic)

The Upanishads consist of ten, twelve or thirteen major texts, with a total of 108 texts (some scholars list ten as principal – the Mukhya Upanishads, while most consider twelve or thirteen as principal, most important Upanishads). The ten Upanishads are Īśā, Kena, Kaṭha, Praṣna, Muṇḍaka, Māṇḍūkya, Taittirīya, Aitareya, Chāndogya and Bṛhadāraṇyaka.

The Bhagavad Gītā is part of the Bhishma Parva of the Mahabhārata.

The Brahma Sūtras (also known as the Vedānta Sūtras), systematize the doctrines taught in the Upanishads and the Gītā.

Founders of the major schools of Vedanta, Adi Shankara, Madhvācharya wrote bhāṣyas (commentaries) on these texts. Rāmānujāchārya did not write any bhāṣya (commentary) on the Upanishads, but wrote bhāṣyas (commentaries) on Brahma Sutras and Bhagavad Gita. Even though Ramanuja did not write individual commentaries on principal Upanishads, he included many hundreds of quotations from Upanishads in his Sri Bhasya. In the Ramanuja lineage, one of his followers, Rangaramanuja, wrote commentaries on almost all of the Principal Upanishads around the 1600s. Vallabhacharya and Nimbarkacharya wrote bhāṣyas (commentaries) on Brahma Sutras and Bhagavad Gita but they did not write commentaries on Upanishads. Like Ramanuja, they quoted many verses from Upanishads in their works.

