सां
⚖️Ā
Sāṃkhya
सांख्य
~700 BCE · Dualist
“Reality is the interplay of two eternal principles — consciousness and matter.”
India’s oldest formal philosophy systemExplore ▾
Core Tenets
- Reality has two eternal, independent principles: Puruṣa (pure consciousness) and Prakṛti (primal matter/nature)
- The universe evolves from Prakṛti through three qualities: Sattva (clarity), Rajas (activity), Tamas (inertia)
- The self (Puruṣa) is a passive witness — suffering arises from mistakenly identifying with the body-mind
- Liberation (Moksha) comes from discriminative knowledge separating Puruṣa from Prakṛti
- Accepts inference and testimony as valid knowledge; rejects a creator God
Key Thinkers
Kapila (founder)ĀsuriPañcaśikhaĪśvarakṛṣṇa
Key Texts
Sāṃkhya KārikāSāṃkhya Sūtras
💡 Remember It AsSāṃkhya = “enumeration.” It painstakingly lists 25 tattvas (fundamental categories) of reality — philosophy’s first periodic table of existence.
यो
🧘Ā
Yoga
योग
~400 BCE · Theist Dualist
“Stilling the fluctuations of the mind is the path to liberation.”
Sāṃkhya’s practical sister — with GodExplore ▾
Core Tenets
- Accepts Sāṃkhya metaphysics but adds Īśvara (God) as a special Puruṣa untouched by karma
- The goal: Chitta-Vṛitti-Nirodhaḥ — complete cessation of mental fluctuations
- Ashtanga (eight-limbed) path: Yama, Niyama, Āsana, Prāṇāyāma, Pratyāhāra, Dhāraṇā, Dhyāna, Samādhi
- Samādhi leads to Kaivalya — isolation of pure consciousness from matter
Key Thinkers
Patañjali (compiler)VyāsaVācaspati Miśra
Key Texts
Yoga Sūtras of PatañjaliBhagavad Gītā
💡 Remember It AsYoga is Sāṃkhya made practical. If Sāṃkhya says “you are the witness, not the mind,” Yoga gives you the exact 8-step method to realize that truth.
न्या
🔍Ā
Nyāya
न्याय
~600 BCE · Realist
“Correct knowledge through correct reasoning is the gateway to liberation.”
India’s great school of logic and debateExplore ▾
Core Tenets
- Four valid sources of knowledge (Pramāṇas): Perception, Inference, Comparison, Testimony
- Famous five-step syllogism: Claim → Reason → Example → Application → Conclusion
- The self (Ātman) is a real, eternal substance provable through inference
- God (Īśvara) exists and can be proved logically — Nyāya offers India’s first formal theistic proofs
Key Thinkers
Gautama / AkṣapādaVātsyāyanaUdayana
Key Texts
Nyāya SūtrasNyāya BhāṣyaNyāya-kusumāñjali
💡 Remember It AsIndia’s Aristotle school. Nyāya built rigorous tools of logic, debate, and proof — then used them to prove God’s existence and demolish rivals in philosophical tournaments called shāstrārtha.
वै
⚛️Ā
Vaiśeṣika
वैशेषिक
~600 BCE · Atomist
“All matter is composed of eternal, indivisible atoms — each unique in its particularity.”
Ancient India’s atomic theory of realityExplore ▾
Core Tenets
- Reality consists of 7 categories (Padārthas): Substance, Quality, Action, Generality, Particularity, Inherence, and Absence
- Matter is composed of eternal, indivisible atoms (paramāṇu) of earth, water, fire, and air
- Each atom has a unique “particularity” (viśeṣa) distinguishing it from all others — hence the school’s name
- Soul (Ātman) and mind (Manas) are distinct, eternal substances — deeply empiricist approach
Key Thinkers
Kaṇāda (founder)Praśastapāda
Key Texts
Vaiśeṣika SūtrasPadārtha Dharma Saṃgraha
💡 Remember It AsAncient India’s Democritus — but richer. Kaṇāda proposed atoms 2,500 years before Dalton. His category system anticipates modern ontology. Eventually merged with Nyāya.
मी
📜Ā
Mīmāṃsā
मीमांसा
~300 BCE · Ritualist
“The Vedas are eternal, self-valid, and authorless — performing their rituals is itself liberation.”
The philosophy of sacred action and dutyExplore ▾
Core Tenets
- The Vedas are apauruṣeya — not composed by any being, human or divine; eternal, self-revealing truth
- The primary purpose of the Vedas is to command ritual action (dharma), not metaphysical description
- Liberation comes through performing Vedic duties flawlessly, without desire for results
- Developed extraordinarily sophisticated philosophy of language and meaning (Sphoṭa theory)
Key Thinkers
Jaimini (founder)ŚabaraKumārila BhaṭṭaPrabhākara
Key Texts
Mīmāṃsā SūtrasŚābara BhāṣyaŚlokavārttika
💡 Remember It As“Ritual philosophy.” If Vedānta asks “What is Brahman?”, Mīmāṃsā asks “What does the Veda command us to do, and how do we do it perfectly?”
ब्र
🌊Ā
Advaita Vedānta
अद्वैत वेदान्त
788–820 CE · Non-Dual
“Brahman alone is real. The world is appearance. You are That — Tat Tvam Asi.”
The pinnacle of Hindu non-dualist thoughtExplore ▾
Core Tenets
- Only Brahman (infinite, undifferentiated consciousness) is ultimately real — Ekam eva advitīyam (“One without a second”)
- The world’s multiplicity is Māyā — not non-existent, but appearance superimposed on Brahman
- Ātman is identical to Brahman — only ignorance (Avidyā) makes it appear separate
- Liberation is not achieved but recognized: direct knowledge “I am Brahman” (Aham Brahmāsmi)
- Three ontological levels: Pāramārthika (absolute), Vyāvahārika (conventional), Prātibhāsika (illusory)
Key Thinkers
Ādi ŚaṅkarācāryaGauḍapādaMaṇḍana MiśraSureśvara
Key Texts
Brahmasūtra BhāṣyaVivekacūḍāmaṇiMāṇḍūkya Kārikā
💡 Remember It AsAdvaita = “not-two.” Like waking from a dream, liberation is realizing there was never a separate self — only Brahman appearing as everything, including you. Śaṅkara died at 32; his impact is incalculable.
वि
🌸Ā
Viśiṣṭādvaita
विशिष्टाद्वैत
1017–1137 CE · Qualified Non-Dual
“God, souls, and world are one organic whole — but real, distinct, and held together as body to soul.”
Devotion and philosophy unitedExplore ▾
Core Tenets
- Brahman (God = Viṣṇu) is real and personal — not featureless like Śaṅkara’s Brahman
- Individual souls and matter are real, but exist as the “body” of Brahman
- Śarīra-Śarīrī relation: God is the inner controller of all; souls and matter are his modes
- Liberation through Bhakti (loving devotion) — dwelling eternally in God’s presence in service
Key Thinkers
RāmānujācāryaNāthamuniYāmunācārya
Key Texts
Śrī BhāṣyaVedārthasaṃgrahaGītābhāṣya
💡 Remember It As“Qualified non-dualism.” Not just one, not truly two — one organic whole. God contains the universe the way a soul animates a body. Rāmānuja’s philosophical counter-punch to Śaṅkara.
द्व
⚡Ā
Dvaita Vedānta
द्वैत वेदान्त
1238–1317 CE · Dualist Theist
“God and soul are eternally, absolutely different — and that difference is the glory of devotion.”
The most radically theistic VedāntaExplore ▾
Core Tenets
- Five fundamental eternal differences (Pañca Bheda): God-Soul, God-Matter, Soul-Soul, Soul-Matter, Matter-Matter
- Viṣṇu alone is supremely independent (Svatantra); all else depends entirely on him
- Individual souls are real, plural, eternal, and forever distinct from God — even in liberation
- Liberation = eternal blissful experience of God’s presence, never merger or identity with him
Key Thinkers
Madhvācārya (Ānandatīrtha)JayatīrthaVyāsatīrtha
Key Texts
Brahmasūtra Bhāṣya (Madhva)Anuvyākhyāna
💡 Remember It AsDvaita = “two” — and Madhva means it absolutely. Unlike Śaṅkara (all is one) or Rāmānuja (one with real parts), Madhva says God and soul remain forever beautifully, lovingly, irreducibly separate.
बु
☸️N
Buddhist Philosophy
बौद्ध दर्शन
~500 BCE · Non-self, Impermanence
“There is no eternal self. All is impermanent. The middle path ends suffering.”
The dharma of non-attachment and awakeningExplore ▾
Core Tenets
- Three Marks of Existence: Anicca (impermanence), Duḥkha (suffering), Anātman (no-self)
- Four Noble Truths: Suffering exists → has a cause (craving) → can cease → Eightfold Path leads to cessation
- Pratītyasamutpāda: Dependent Origination — all phenomena arise in dependence on conditions
- Four sub-schools: Vaibhāṣika, Sautrāntika, Yogācāra (mind-only), Mādhyamaka (emptiness)
- Nirvāṇa = extinction of craving and the illusion of self — beyond conceptualization
Key Thinkers
Gautama BuddhaNāgārjunaVasubandhuDignāgaDharmakīrti
Key Texts
DhammapadaMūlamadhyamakakārikāAbhidharmakośa
💡 Remember It AsBuddhism rejects both eternal self (Hinduism’s Ātman) and total annihilation (nihilism). The “middle path” is not a compromise — it’s a radical third position that dissolves the question entirely.
ज
🕊️N
Jaina Philosophy
जैन दर्शन
~600 BCE · Pluralist Realist
“Every living being has an eternal soul. Non-violence in thought, word, and deed is the supreme religion.”
Philosophy of non-violence and many-sidednessExplore ▾
Core Tenets
- Anekāntavāda: reality is many-sided — any single perspective is partial truth (Nayavāda)
- Syādvāda: all claims should be qualified with “in some respect” (syāt) — conditional predication
- Reality consists of souls (Jīvas) and non-soul matter (Ajīvas) — both real and eternal
- The soul is weighed down by karma (conceived as subtle matter), causing rebirth
- Liberation through Tri-Ratna: Right Knowledge, Right Faith, Right Conduct (especially Ahiṃsā)
Key Thinkers
Mahāvīra (24th Tīrthaṃkara)UmāsvātiKundakundaHemacandra
Key Texts
TattvārthasūtraĀgamasSamayasāra
💡 Remember It AsRadical pluralism + radical non-violence. Syādvāda anticipates multi-valued logic systems. “Maybe yes, maybe no, maybe both, maybe neither” — not vagueness, but philosophical precision.
चा
🔥N
Cārvāka / Lokāyata
चार्वाक
~600 BCE · Materialist
“Only matter is real. Only perception is valid knowledge. This life is all there is.”
India’s radical materialist and skeptic schoolExplore ▾
Core Tenets
- Only four material elements are real: earth, water, fire, air. Consciousness is their by-product
- Only direct perception (Pratyakṣa) is valid knowledge — inference and testimony are unreliable
- No soul, no afterlife, no karma, no God — all are priestly inventions to control the credulous
- The highest good is pleasure (Sukha) in this life; pain is the only evil. Moksha is meaningless
Key Thinkers
Bṛhaspati (legendary founder)Ajita Keśakambalī
Key Texts
Bṛhaspati Sūtra (lost)Tattvopaplava Siṃha
💡 Remember It AsIndia’s Epicureans and Skeptics combined. Cārvāka survived mainly through opponents’ refutations — a philosophy so dangerous its own texts were nearly all destroyed.
आ
🌀N
Ājīvika
आजीविक
~500 BCE · Fatalist
“Everything is fixed by cosmic fate. Free will is an illusion. Liberation comes automatically, in due course.”
The ancient philosophy of absolute determinismExplore ▾
Core Tenets
- Niyati (fate/destiny) governs everything absolutely — human effort and free will are complete illusions
- Every soul will attain liberation after exactly 8,400,000 mahā-kalpas of rebirth — not one moment sooner
- Karma is acknowledged but rendered impotent — actions neither help nor hinder one’s path
- Once a major rival of Buddhism and Jainism; now extinct with no surviving texts
Key Thinkers
Makkhali Gosāla (founder)Pūraṇa Kassapa
💡 Remember It AsRadical cosmic determinism. If everything is inevitable, what’s the point of philosophy? The Ājīvikas had an answer: live simply, and wait — liberation is on schedule.
अ
❓N
Ajñāna
अज्ञान
~600 BCE · Radical Skeptic
“No knowledge is possible. No position can be defended. Philosophy itself is the problem.”
Ancient India’s school of radical agnosticismExplore ▾
Core Tenets
- Any philosophical assertion can be met with an equally valid counter — certainty is impossible
- Radical skepticism applied universally: metaphysics, ethics, epistemology — all are suspect
- The only honest response to metaphysical questions: suspension of all judgment (Vikhepavāda)
- Influenced Buddhist Mādhyamaka and parallels Pyrrhonian skepticism in ancient Greece
Key Thinkers
Sañjaya Belaṭṭhaputta
💡 Remember It AsIndia’s Pyrrhonists — the philosophically honest response to competing schools. Sañjaya answered every metaphysical question with an elaborate “I neither assert it is so, nor not-so, nor both, nor neither.”
यो
💭N
Yogācāra
योगाचार
~300 CE · Mind-Only
“There is no external world — only streams of consciousness presenting the appearance of objects.”
Buddhism’s idealist school — mind is allExplore ▾
Core Tenets
- Vijñaptimātratā: only representations (vijñapti) exist — there is no external matter independent of mind
- Ālaya-vijñāna: the “storehouse consciousness” — a deep mental stream that stores karmic seeds and generates experience
- Three natures: imagined (parikalpita), dependent (paratantra), perfected (pariniṣpanna)
- Liberation = transformation of the storehouse consciousness from ignorance to wisdom (āśraya-parāvṛtti)
Key Thinkers
AsaṅgaVasubandhuDharmapālaXuanzang
Key Texts
YogācārabhūmiVijñaptimātratāsiddhiTriṃśikā
💡 Remember It As“Mind-only.” Everything you experience — this page, your body, sounds — is a projection of mind-streams with no independent material basis. A Buddhist answer to Descartes, 1,200 years earlier.