To found a school of Vedanta you must do one thing: write a commentary on the prasthana trayi — the three starting points. Not one of them, not two. All three, in full. It is the most demanding entry requirement any philosophical tradition has imposed on itself, and it is the reason the great acharyas produced bodies of work that can be compared line against line.
📚 The Prasthana Trayi at a Glance
Prasthana: a departure point, a place one sets out from
1. Shruti prasthana: the Upanishads — revelation
2. Nyaya prasthana: the Brahma Sutras — reasoning
3. Smriti prasthana: the Bhagavad Gita — remembered tradition
Requirement: a full bhashya on all three, to claim a place in Vedanta
Upanishads: conventionally the ten Shankara commentated
📑 Table of Contents
🗺️ The Three, and Why These Three
| Prasthana | Text | Its authority rests on | What it supplies |
|---|---|---|---|
| Shruti | The Upanishads | Revelation — what was heard | The primary statements. Everything else must be shown to agree with these |
| Nyaya | The Brahma Sutras | Reasoning | The system. It reconciles the Upanishads' apparent conflicts and answers objections |
| Smriti | The Bhagavad Gita | Remembered tradition | The application. It states the teaching for a person who has to act |
📌 The three cover three different obligations
A philosophy has to be grounded in something authoritative, coherent under examination, and livable by someone who is not a renunciate. The prasthana trayi assigns one text to each. A commentator who handled only the Upanishads could be accused of cherry-picking; one who handled only the sutras could be accused of building a system detached from revelation; one who handled only the Gita could be accused of preaching without foundations. Requiring all three closes every route.
📖 Which Upanishads
The Muktika Upanishad lists 108, but the shruti prasthana in practice means the principal ones on which the acharyas wrote. The conventional list is the ten Shankara commentated:
| Upanishad | Veda |
|---|---|
| Isha | Shukla Yajur |
| Kena | Sama |
| Katha | Krishna Yajur |
| Prashna | Atharva |
| Mundaka | Atharva |
| Mandukya | Atharva |
| Taittiriya | Krishna Yajur |
| Aitareya | Rig |
| Chandogya | Sama |
| Brihadaranyaka | Shukla Yajur |
✍️ What a Bhashya Has to Do
A commentary in this tradition is not paraphrase. To count, it must:
- Resolve every compound and every ambiguity in the base text explicitly — Sanskrit compounds admit several analyses, and the commentator must state which he takes and why.
- Show the passage agrees with the rest of scripture, including passages that appear to say the opposite.
- State the opponents' readings — the purvapaksha — in their strongest form, and answer them.
- Establish the section's purport using the standard six criteria taken from Mimamsa: beginning and end, repetition, novelty, result, praise and reasoning.
- Be internally consistent across all three prasthanas — and this is the real constraint. A reading of a Gita verse that requires a Brahman with attributes cannot sit beside an Upanishadic commentary that denies them.
💡 Why this makes comparison possible
Because every school commentated the same three texts under the same rules, their disagreements are exactly locatable. One can put Shankara's, Ramanuja's and Madhva's treatment of a single sutra side by side and see precisely where the paths diverge — often at the resolution of one compound. Very few intellectual traditions anywhere are arranged so that rival systems can be diffed against each other this cleanly.
👤 Who Completed It
| Acharya | School | Principal commentaries |
|---|---|---|
| Shankara | Advaita | Brahma Sutra Bhashya; Gita Bhashya; commentaries on the ten Upanishads |
| Ramanuja | Vishishtadvaita | Sri Bhashya; Gita Bhashya; Vedartha Sangraha |
| Madhva | Dvaita | Brahma Sutra Bhashya and Anuvyakhyana; Gita Bhashya and Tatparya Nirnaya; Upanishad bhashyas |
| Nimbarka | Dvaitadvaita | Vedanta Parijata Saurabha, with the tradition's fuller commentaries by Shrinivasa |
| Vallabha | Shuddhadvaita | Anubhashya; Subodhini on the Bhagavata; Gita commentary |
❓ Frequently Asked Questions
What is the prasthana trayi?
The three foundational texts of Vedanta: the Upanishads (shruti prasthana, revelation), the Brahma Sutras (nyaya prasthana, reasoning), and the Bhagavad Gita (smriti prasthana, remembered tradition). Prasthana means a departure point. An acharya must commentate all three.
Why must all three be commentated?
They cover three different obligations: a philosophy must be grounded in something authoritative, coherent under examination, and livable by someone who has to act. Handle only the Upanishads and you can be accused of cherry-picking; only the sutras, of building a system detached from revelation; only the Gita, of preaching without foundations. Requiring all three closes every route.
Which Upanishads count as the shruti prasthana?
Conventionally the ten Shankara commentated: Isha, Kena, Katha, Prashna, Mundaka, Mandukya, Taittiriya, Aitareya, Chandogya, Brihadaranyaka. But this is a convention, not a canon — different acharyas commentated different sets, the Shvetashvatara and Kaushitaki matter to several schools and fall outside it, and the Brahma Sutras discuss passages from beyond the list.
What does a bhashya have to do to count?
Resolve every compound and ambiguity explicitly; show the passage agrees with the rest of scripture including apparent contradictions; state opponents' readings in their strongest form and answer them; establish purport by the six Mimamsa criteria; and be internally consistent across all three prasthanas — which is the real constraint. A Gita reading requiring a Brahman with attributes cannot sit beside an Upanishadic commentary denying them.
🙏 Conclusion
The prasthana trayi is three texts and one rule: ground the position in revelation, systematise it against objection, and show it can be lived. Commentate all three or you are not doing Vedanta. The rule produced enormous labour and one unusual benefit — because every school worked the same three texts under the same constraints, their disagreements can be located to the exact word where they part.