Overview — Astika vs Nastika Schools
Ancient Indian philosophical thought is broadly divided into two categories based on their relationship to Vedic authority:
| Category | Definition | Schools |
|---|---|---|
| Astika (Orthodox) | Accept the authority and validity of the Vedas as a source of knowledge | Six Darshanas: Nyaya, Vaisheshika, Samkhya, Yoga, Mimamsa, Vedanta |
| Nastika (Heterodox) | Do not accept Vedic authority as supreme or reject it entirely | Buddhism, Jainism, Charvaka/Lokayata |
Important note: The term "Nastika" does not mean "atheist" in the Western sense — Jainism, for example, accepts the existence of souls and karma but rejects the Vedas' authority. Even within astika schools, there are significant debates about the nature of God.
The six orthodox schools are collectively called Shad Darshana (six viewpoints/visions). They emerged and developed primarily between 600 BCE and 300 CE, though their foundational texts were composed over a long period.
The Six Orthodox Darshanas (Shad Darshana)
1. Nyaya — The School of Logic
Founder: Sage Gautama (also called Aksapada Gautama), who composed the Nyaya Sutras
Core focus: Logic, epistemology (theory of knowledge), and correct methods of argumentation
Central concern: How do we know what we know? What are the valid means of acquiring knowledge (pramana)?
| Concept | Explanation |
|---|---|
| Pramanas (valid sources of knowledge) | Nyaya accepts 4 pramanas: pratyaksha (perception), anumana (inference), upamana (comparison/analogy), sabda (verbal testimony) |
| 16 Padarthas (categories) | The Nyaya system categorises reality into 16 categories — including pramana (sources), prameya (objects of knowledge), samshaya (doubt), prayojana (purpose), vada (debate), drishthanta (examples) |
| Anumana (inference) | The most developed part of Nyaya — a formal syllogism (nyaya) using vyapti (invariable concomitance/pervasion) |
| Liberation (apavarga) | Attained through right knowledge, freeing the soul from bondage |
Classic Nyaya syllogism:
- Pratijña (proposition): The hill has fire
- Hetu (reason/evidence): Because there is smoke
- Udaharana (example): Wherever there is smoke, there is fire — like in a kitchen
- Upanaya (application): This hill has smoke
- Nigamana (conclusion): Therefore this hill has fire
UPSC significance: The Nyaya tradition developed into one of the world's earliest formal logics; influenced Buddhist and Jain philosophy too.
2. Vaisheshika — Atomic Pluralism
Founder: Sage Kanada (also called Uluka), who composed the Vaisheshika Sutras
Core focus: Ontology (nature of reality), atomism, and natural philosophy
| Concept | Explanation |
|---|---|
| Six Padarthas (categories) | Dravya (substance), Guna (quality), Karma (action), Samanya (universal), Vishesha (particularity), Samavaya (inherence) — a seventh, abhava (non-existence), was added later |
| Paramanu (atoms) | Matter is composed of indivisible eternal atoms (paramanu); different atoms form earth, water, fire, air |
| Non-atomic substances | Space (akasha), time (kala), space/direction (dik), soul (atman), mind (manas) are eternal but non-atomic |
| Relationship with Nyaya | The two schools are closely allied — together called Nyaya-Vaisheshika; they share similar views on liberation through knowledge |
Kanada's atomic theory (c. 6th–2nd century BCE) predates the Greek atomists Democritus and Leucippus or is roughly contemporaneous — a remarkable proto-scientific contribution.
3. Samkhya — Dualistic Cosmology
Founder: Sage Kapila, traditionally credited with the Samkhya Sutras (though Ishvarakrishna's Samkhyakarika is the classical text)
Core focus: Metaphysical dualism between consciousness and matter
| Concept | Explanation |
|---|---|
| Purusha (consciousness) | Pure passive consciousness; multiple individual selves; neither acts nor changes |
| Prakriti (matter/nature) | The active, dynamic, unconscious material cause of the universe; single undifferentiated primordial matter |
| Evolution of the universe | When Purusha comes into proximity with Prakriti, evolution occurs: Prakriti produces Mahat (cosmic intelligence) → Ahamkara (ego) → 5 sense organs, 5 motor organs, mind, 5 tanmatras (subtle elements), 5 mahabhutas (gross elements) — totalling 25 tattvas |
| Three Gunas | Prakriti has three constituent qualities: Sattva (purity/lightness), Rajas (activity/passion), Tamas (inertia/darkness). Their interplay drives all change |
| Liberation (Kaivalya) | Through discriminative knowledge (Vivekakhyati) — realising that Purusha is distinct from Prakriti; liberation is isolation of pure consciousness |
| Theism | Classical Samkhya is typically non-theistic — it does not require God to explain creation; Prakriti is the material cause |
Yoga relationship: Patanjali's Yoga school accepts Samkhya's metaphysics but adds the concept of Ishvara (a special, unaffected Purusha — God) and prescribes practical methods (asanas, pranayama, meditation) to achieve liberation.
4. Yoga — Path of Liberation through Practice
Founder: Sage Patanjali, who compiled the Yoga Sutras (c. 200 BCE–400 CE)
Core focus: Practical method for achieving liberation through mental discipline and the cessation of mental modifications (chitta vritti nirodha)
| Concept | Explanation |
|---|---|
| Metaphysics | Accepts Samkhya's Purusha-Prakriti dualism; adds Ishvara (God) as a special liberated self |
| Goal | Chitta vritti nirodha — cessation of the fluctuations of the mind; leads to Kaivalya (liberation) |
| Ashtanga Yoga (Eight Limbs) | The systematic path described in the Yoga Sutras |
The Eight Limbs of Ashtanga Yoga:
| Limb | Sanskrit | Meaning |
|---|---|---|
| 1 | Yama | Ethical restraints (ahimsa, satya, asteya, brahmacharya, aparigraha) |
| 2 | Niyama | Observances (saucha, santosha, tapas, svadhyaya, Ishvara pranidhana) |
| 3 | Asana | Physical postures — stability and comfort |
| 4 | Pranayama | Breath control |
| 5 | Pratyahara | Withdrawal of senses from external objects |
| 6 | Dharana | Concentration on a single object |
| 7 | Dhyana | Meditation — sustained concentration |
| 8 | Samadhi | Absorption — the final state of unity with the object of meditation; liberation |
The inner four (Pratyahara to Samadhi) constitute Samyama — the highest practices.
5. Mimamsa — Vedic Ritualism and Dharma
Founder: Sage Jaimini, who composed the Mimamsa Sutras (also called Purva Mimamsa Sutras)
Core focus: Correct interpretation of Vedic injunctions (vidhis) and the nature of dharma — the obligatory Vedic duties
| Concept | Explanation |
|---|---|
| Sabda-pramana (verbal testimony) | Sabda (the Vedas as eternal sound) is the primary valid source of knowledge — the Vedas are self-validating, authorless (apaurusheya) and eternal |
| Dharma | Dharma = Vedic injunction (vidhi); what ought to be done; not knowable through perception or inference but only through Vedic testimony |
| Svarga (heaven) | Rituals performed properly lead to the attainment of heaven; later Mimamsa debated liberation |
| Apurva | The unseen potency generated by a ritual that bridges the performance of a rite and its future fruit — a form of moral causality |
| God | Classic Mimamsa is typically non-theistic — rituals work by their own power, without requiring a God |
| Kumarila Bhatta and Prabhakara | Two important sub-schools within Mimamsa; differed on the nature of error and the grounds of validity of knowledge |
Mimamsa's philosophical influence was immense — it was the guardian of Brahmanical orthopraxis and its debates with Buddhism shaped much of classical Indian intellectual history.
6. Vedanta — The Philosophy of the Upanishads
Founder: Sage Badarayana (also identified as Vyasa), who composed the Brahma Sutras (also called Vedanta Sutras or Uttara Mimamsa Sutras)
Core texts (Prasthanatrayi):
- Upanishads (primary)
- Bhagavad Gita
- Brahma Sutras (Badarayana)
Core focus: Nature of Brahman (ultimate reality), Atman (individual soul), and the relationship between the two
Vedanta developed into multiple sub-schools, the three most significant being:
| Sub-School | Founder | Period | Core Teaching |
|---|---|---|---|
| Advaita (Non-dualism) | Adi Shankaracharya | ~788–820 CE | Brahman alone is real; Atman = Brahman; the world is maya (illusion/appearance) |
| Vishishtadvaita (Qualified Non-dualism) | Ramanuja | ~1017–1137 CE | Brahman is real, the world and souls are real but exist as attributes of Brahman — qualified unity |
| Dvaita (Dualism) | Madhvacharya | ~1238–1317 CE | Brahman (Vishnu) and individual souls are eternally distinct and independent realities |
Advaita Vedanta (Shankaracharya)
- Brahman is the only ultimate reality — infinite, undifferentiated pure consciousness
- Atman (individual self) is identical to Brahman: Tat Tvam Asi ("That Thou Art") — Chandogya Upanishad
- Maya: The world appears real through the power of maya (cosmic illusion/ignorance) but has no ultimate ontological status (mithya — neither real nor unreal)
- Two levels of truth: Vyavaharika (conventional/empirical truth — the world exists in practice) and Paramarthika (ultimate truth — only Brahman exists)
- Liberation (Moksha): Through jnana (knowledge) — realising the identity of Atman and Brahman
- Shankaracharya also established four mathas (monasteries) at Sringeri, Dwarka, Puri, and Joshimath (Badrinath) — consolidating Hindu philosophical thought
Vishishtadvaita (Ramanuja)
- Brahman is real and personal — identified with Vishnu/Narayana (Saguna Brahman with attributes)
- The world and individual souls are real but constitute the "body" of Brahman — they are not illusion
- Jiva (individual soul) and jagat (world) are real but exist in a relation of apritak-siddhi (inseparable existence) with Brahman
- Liberation: Through bhakti (devotion) combined with jnana and karma — the soul attains proximity (not merger) with Brahman
- Ramanuja's philosophy influenced the Bhakti movement strongly — particularly the Vaishnava traditions
Dvaita Vedanta (Madhvacharya)
- Five eternal distinctions (pancha-bheda): Between God and soul; between God and matter; between soul and matter; between individual souls; between material objects
- Brahman (Vishnu) is the only independent reality (svatantra) — souls and matter are dependent (paratantra)
- Souls are eternally distinct from God — liberation means eternal life in the presence of Vishnu, not merger
- Madhvacharya's tradition headquartered at Udupi (Karnataka)
Heterodox Schools (Nastika Darshanas)
1. Buddhism
Buddhism rejected Vedic authority and the caste system. Its philosophical development is vast:
| School | Key Figure | Core Concept |
|---|---|---|
| Theravada/Hinayana | Traditional — attributed to historical Buddha | Dependent origination (pratityasamutpada), Four Noble Truths, Eightfold Path |
| Madhyamaka | Nagarjuna (c. 150–250 CE) | Sunyavada — all phenomena are empty (sunya) of inherent existence; the middle way between existence and non-existence |
| Yogacara / Vijnanavada | Asanga and Vasubandhu (4th–5th CE) | "Mind-only" (cittamatra) — external reality is a projection of consciousness |
| Buddhist Logic/Epistemology | Dignaga (5th CE) and Dharmakirti (7th CE) | Developed a rigorous pramana (epistemology) tradition; influenced Nyaya debates; only perception and inference as valid |
Nagarjuna's Madhyamaka: The most influential Buddhist philosophical school globally — "sunyata" (emptiness) does not mean nihilism but the absence of svabhava (inherent/self-subsistent nature) in all phenomena. This underpinned Mahayana Buddhism's emphasis on compassion and the Bodhisattva path.
2. Jainism — Many-Sidedness of Truth
Jainism developed a sophisticated epistemology rooted in its metaphysics of multiple independent souls:
| Concept | Meaning |
|---|---|
| Anekantavada | Doctrine of the many-sidedness of reality — reality has multiple aspects; no single viewpoint captures the whole truth |
| Syadvada (Saptabhangi) | Theory of conditional predication — any statement about reality must be qualified with syat ("in some respect" / "perhaps"); 7 possible qualified truth-values |
| Nayavada | Theory of partial perspectives (naya = viewpoint); every assertion is made from a particular standpoint |
| Ahimsa | Non-violence as the supreme ethical principle — extends to all living beings; basis for Jain dietary practices |
| Karma (Jain view) | Karma is a physical substance (karma vargana) that attaches to the soul, binding it; liberation through shedding karma |
UPSC relevance: Anekantavada is cited as an ancient Indian contribution to tolerance and pluralism; Gandhi acknowledged its influence on his thought.
3. Charvaka / Lokayata — Indian Materialism
The Charvaka (or Lokayata) school is India's ancient materialist philosophy — the only school that rejected all metaphysical speculation.
| Concept | Position |
|---|---|
| Epistemology | Only pratyaksha (perception) is a valid source of knowledge — inference is unreliable since vyapti (invariable concomitance) cannot be established through perception alone |
| Metaphysics | Only the four material elements (earth, water, fire, air) are real; consciousness arises from matter |
| Soul | No immortal soul — consciousness is a product of the body; ceases at death |
| Afterlife | No afterlife, no rebirth, no karma, no liberation |
| Ethics | Hedonism — the pursuit of pleasure (kama) and avoidance of pain is the purpose of life; dharma and moksha are superfluous |
| God | Atheistic — no creator God |
Charvaka writings have largely survived only through quotations in rival texts (Shankaracharya's commentary, Jayanta Bhatta's Nyayamanjari, etc.) — a remarkable case of philosophical transmission through refutation.
Indian Epistemology — Pramanas (Valid Sources of Knowledge)
Different schools accepted different numbers of valid knowledge sources:
| Pramana | Meaning | Schools Accepting |
|---|---|---|
| Pratyaksha (Perception) | Direct sensory perception | All schools (Charvaka: only this) |
| Anumana (Inference) | Logical inference through vyapti (universal relation) | All except Charvaka |
| Upamana (Comparison) | Knowledge through analogy — knowing a new thing by comparing to a known thing | Nyaya, Mimamsa |
| Sabda (Verbal Testimony) | Reliable testimony — Vedas or trustworthy person | Most schools; elevated to supreme by Mimamsa |
| Arthapatti (Postulation) | Presumption — inferring an unexpressed fact to explain an apparent contradiction | Mimamsa, Advaita |
| Anupalabdhi (Non-perception) | Knowledge of absence — knowing a pot is not on the table by not perceiving it | Mimamsa, Advaita |
| School | Pramanas Accepted | Count |
|---|---|---|
| Charvaka | Pratyaksha only | 1 |
| Buddhism (Dignaga/Dharmakirti) | Pratyaksha, Anumana | 2 |
| Samkhya-Yoga | Pratyaksha, Anumana, Sabda | 3 |
| Nyaya | Pratyaksha, Anumana, Upamana, Sabda | 4 |
| Mimamsa, Advaita Vedanta | All six | 6 |
Relevance for UPSC Ethics (GS4)
Ancient Indian philosophical traditions have direct relevance for GS4 (Ethics, Integrity and Aptitude):
| Tradition | Ethical Contribution | Modern Connection |
|---|---|---|
| Yoga (Patanjali) — Yamas | Ahimsa, Satya, Asteya as universal ethical principles | Gandhi's satyagraha; Ambedkar's rights discourse |
| Jain Anekantavada | Tolerance, humility about one's own viewpoint | Constitutional secularism; pluralistic democracy |
| Advaita Vedanta | Unity of all beings (Vasudhaiva Kutumbakam) | Vivekananda's universal ethics; universal brotherhood |
| Buddhist Madhyamaka | Middle path; compassion for all sentient beings | B.R. Ambedkar's turn to Buddhism; compassion in governance |
| Mimamsa — Dharma | Duty-based ethics; obligation without expectation of personal gain | Resonates with Kant's deontological ethics; Gita's Nishkama Karma |
| Samkhya — Gunas | Understanding human nature (sattva/rajas/tamas) as basis for leadership character | Civil services character formation; administrative ethics |
Previous Year Questions (PYQs)
Prelims
-
(UPSC CSE Prelims 2021): "With reference to Indian history, the term 'Anekantavada' is most closely associated with which of the following?"
- Jainism — the doctrine of many-sidedness of reality.
-
(UPSC CSE Prelims 2020): "In the context of Indian philosophy, the 'Vyapti' is associated with which school?"
- Nyaya — vyapti is the principle of invariable concomitance used in inference (anumana).
-
(UPSC CSE Prelims 2018): "'Pratyaksha', 'Anumana', 'Upamana' and 'Sabda' are the four Pramanas of which school of Indian philosophy?"
- Nyaya school.
-
(UPSC CSE Prelims 2014): "Who among the following is associated with the founding of the Dvaita school of Vedanta?"
- Madhvacharya.
Mains
-
(UPSC CSE Mains GS1 2022): "Discuss the major philosophical schools of ancient India. How do they contribute to understanding Indian civilisation?" (250 words)
-
(UPSC CSE Mains GS4 2021): "How are ancient Indian ethical concepts relevant to the ethics of public service? Illustrate with examples from specific philosophical schools." (150 words)
-
(UPSC CSE Mains GS1 2019): "What is the significance of Shankaracharya's Advaita Vedanta in the context of Indian philosophical tradition? How did it differ from Ramanuja's Vishishtadvaita?" (200 words)
-
(UPSC CSE Mains GS4 2015): "The Charvaka school is sometimes dismissed as mere hedonism. Evaluate the philosophical contributions of the Charvaka/Lokayata tradition to Indian epistemology." (150 words)
Exam Strategy
For Prelims:
- Pair each Darshana with its founder: Nyaya–Gautama, Vaisheshika–Kanada, Samkhya–Kapila, Yoga–Patanjali, Mimamsa–Jaimini, Vedanta–Badarayana
- Vedanta sub-schools: Advaita–Shankaracharya (non-dual, maya), Vishishtadvaita–Ramanuja (qualified non-dual), Dvaita–Madhvacharya (dualist, Udupi)
- Pramanas: Charvaka=1, Buddhist=2, Samkhya=3, Nyaya=4, Mimamsa/Advaita=6
- Anekantavada = Jainism; Sunyavada = Nagarjuna/Buddhism; Vivekakhyati = Samkhya liberation
- Charvaka: perception only, materialist, hedonist, no soul/afterlife
For Mains (GS1 + GS4):
- GS1 asks about ancient philosophical contributions — structure your answer: Orthodox (Shad Darshana) → Heterodox (B, J, C) → Legacy
- GS4 (Ethics): Always link philosophical concepts to modern administrative ethics — Yamas as civil service conduct; Anekantavada as tolerance; Nishkama karma as public duty
- Compare Indian and Western traditions: Nyaya syllogism vs Aristotelian syllogism; Charvaka vs Greek materialists; Indian pramana vs Western epistemology
- Shankaracharya's mathas — national integration significance (4 corners of India)
Mnemonic for Six Darshanas: N-V-S-Y-M-V = Nyaya, Vaisheshika, Samkhya, Yoga, Mimamsa, Vedanta (Never Visit Strange Yellow Mountain Villages)
BharatNotes