RBSE VU Nyaya Darshan cheat sheet

Nyaya is one of the six astika (orthodox) darshanas; it accepts the authority of the Vedas and is paired with Vaisheshika in the nyaya-vaisheshika syncretic tradition.

Founded by Gautama (also called Akshapada, 'gautama' being the gotra name); the foundational text is the Nyaya Sutra (c. 2nd century CE or earlier).

The word nyaya means 'that by which the mind is led to a conclusion'-i.e., logical method or inference; the school is also called tarka-shastra, hetu-shastra, or vadartha.

Core aim: attainment of the highest good (nihshreyasa) through right knowledge (tattva-jnana) of the sixteen padarthas; knowledge of reality leads to liberation.

The Nyaya Sutra opens: 'athato nyaya-vidya vyakhyasyamah'-now the science of nyaya will be expounded; the first sutra states that liberation is attained by knowledge of the true nature of the padarthas.

Place among astika darshanas: Nyaya and Vaisheshika are allied (Nyaya focuses on pramana/logic, Vaisheshika on ontology/padarthas); Samkhya-Yoga form another pair; Mimamsa and Vedanta are exegetical schools.

Key early commentators: Vatsyayana (Nyaya Bhasya), Udyotakara (Nyaya Varttika), Vacaspati Mishra (Nyaya Varttika-tatparya-tika), Udayana (Nyaya Kusumanjali, Atma-tattva-viveka), Jayanta (Nyaya Manjari).

Navya-Nyaya ('new Nyaya') begins with Gangesha's Tattva-cintamani (c. 12th–13th century); it developed a formal technical language (vyapti, paksha, etc.) and influenced Indian logic and epistemology broadly.

Basic terminology: pramana (means of knowledge), prameya (object of knowledge), pramata (knower), pramiti (valid cognition), samshaya (doubt), prayojana (purpose), drishtanta (example), siddhanta (established doctrine), avayava (member of inference), tarka (hypothetical reasoning), nirnaya (settled conclusion).

Pramana = the instrument or means of valid cognition (prama); Nyaya accepts four pramanas: pratyaksha (perception), anumana (inference), upamana (comparison/analogy), and shabda (verbal testimony).

Pratyaksha: cognition produced by sense-object contact (indriya-artha-sannikarsha); it is nirvikalpaka (indeterminate, non-conceptual) or savikalpaka (determinate, conceptual); it must be non-erroneous (avyabhicari) and free from doubt.

Anumana: knowledge of sadhya (probandum) through hetu (reason) based on vyapti (invariable concomitance) between hetu and sadhya; e.g., 'the hill has fire because it has smoke' (smoke is the hetu, fire the sadhya).

Upamana: knowledge of a thing through its similarity to a known thing; classic example-a person who knows 'gavaya' (wild ox) by resemblance to a cow, upon seeing a gavaya, recalls the similarity and knows 'this is gavaya'.

Shabda: knowledge derived from the utterance of a reliable person (apta-vakya); it requires the speaker to be trustworthy (apta) and the sentence to be well-formed; it is of two kinds: drishtartha (perceptible) and adrishtartha (imperceptible, e.g., heaven, liberation).

Validity (pramanya): Nyaya holds both svatah-pramanya (intrinsic validity) and paratah-apramanya (extrinsic invalidity) for some cases; more precisely, validity is intrinsic to the cognition but known through the conditions that produce it, while invalidity is extrinsic and known through defeating conditions.

Each pramana has its own pramanya (validity) and apramanya (invalidity); a cognition is valid if it corresponds to the real nature of the object (yathartha) and is free from doubt and error.

Nyaya rejects the Buddhist view that perception is bare sensation (nirvikalpaka only); it admits savikalpaka perception as valid, involving conceptual determination (nama, jati, etc.).

Pramana-samplava (Nyaya) vs. pramana-vyavastha (Mimamsa): Nyaya holds that the same object can be known by more than one pramana; Mimamsa holds that each pramana has its own exclusive domain.

The sixteen padarthas (categories) of Nyaya: (1) pramana, (2) prameya, (3) samshaya, (4) prayojana, (5) drishtanta, (6) siddhanta, (7) avayava, (8) tarka, (9) nirnaya, (10) vada, (11) jalpa, (12) vitanda, (13) hetvabhasa, (14) chala, (15) jati, (16) nigrahasthana.

Prameya (the knowable) includes: atma (self), sharira (body), indriya (senses), artha (objects), buddhi (intellect), manas (mind), pravrtti (activity), dosha (defects), pretyabhava (rebirth), phala (fruits of action), dukha (suffering), apavarga (liberation).

Jnana (knowledge/cognition) is defined as apprehension (upalabdhi) or consciousness; it is either valid (prama) or invalid (aprama); valid knowledge is yathartha (true to the object) and anubhava (not memory).

Bhrama (error): false cognition, e.g., mistaking a rope for a snake; Nyaya explains it as a combination of real elements (rope) and false imposition (snake) due to defective conditions (dosha), not as pure illusion.

Samsaya (doubt): a state of uncertainty with two or more alternatives, e.g., 'Is this a post or a man?'; it arises from common properties, dubious perception, conflicting testimony, or irregularity; it is a precondition for inquiry (vicara).

Nyaya's theory of error is called akhyati (non-apprehension) or anyatha-khyati (misapprehension): error is misapprehension of one thing as another, not the apprehension of a non-existent object (as in Buddhist asat-khyati).

Nirnaya (settled conclusion) arises after doubt and inquiry; it is the definite determination of an object through pramana.

Tarka (hypothetical reasoning) is a mental exploration of alternatives to aid nirnaya; it is not itself a pramana but a subsidiary aid (upaya) to inference.

Anumana (inference) has five members (avayava): (1) pratijna (thesis), (2) hetu (reason), (3) udaharana (example), (4) upanaya (application), (5) nigamana (conclusion).

Pratijna: the proposition to be proved, e.g., 'The hill has fire' (parvato vahniman). Hetu: the reason, e.g., 'because it has smoke' (dhumat). Udaharana: the example, e.g., 'like a kitchen' (yatha mahasah). Upanaya: application, e.g., 'this hill has smoke' (ayam ca dhumat). Nigamana: conclusion, e.g., 'therefore the hill has fire' (tasmad vahniman).

Paksha (subject/minor term): the locus where the sadhya is to be proved, e.g., the hill; it must be free from the defect of asiddha (unproved) or viruddha (contradictory).

Sadhya (probandum/major term): what is to be proved, e.g., fire; hetu (reason/middle term): the evidence, e.g., smoke; vyapti: the invariable relation between hetu and sadhya.

Vyapti (invariable concomitance): 'wherever smoke, there fire'; it is known through repeated observation (anvaya) and elimination (vyatireka), or through tarka; it must be unconditional (nirupadhika) to be valid.

Hetvabhasa (fallacy of reason): five kinds-(1) savyabhichara (deviating/inconclusive), (2) viruddha (contradictory), (3) prakaranasama (counter-thesis), (4) sadhyasama (unproved), (5) kalatita (mistimed/overdue).

Savyabhichara: hetu present where sadhya is absent, e.g., 'sound is eternal because it is audible' (audibility is not invariably linked to eternity).

Viruddha: hetu that proves the opposite of the sadhya, e.g., 'sound is eternal because it is produced' (production implies non-eternity).

Tarka (hypothetical reasoning): a process of supposing an alternative and showing its absurdity, used to establish vyapti or remove doubt; it is not a pramana but a helpful aid (upaya).

Vada: a legitimate debate aimed at establishing truth (tattva-nirnaya), conducted with a sincere opponent; it requires the debater to have a thesis (pratijna) and to use valid pramanas.

Jalpa: a debate aimed at victory (vijaya) rather than truth; it permits the use of chala (quibbling), jati (sophisticated refutations), and nigrahasthana (defeat tactics) to win.

Vitanda: a debate where the opponent only attacks the thesis without establishing a counter-thesis; it is a destructive debate, often used to refute without commitment.

Chala (quibbling): misinterpretation of a statement by taking a word in a different sense; three types: vak-chala (verbal), samanya-chala (generic), upacara-chala (figurative).

Jati (sophisticated refutation): a fallacious argument that attempts to refute the opponent by similarity or dissimilarity; it is not a valid pramana but a debate tactic; there are many varieties (e.g., sadharmya-jati, vaidharmya-jati).

Nigrahasthana (grounds of defeat): conditions under which a debater loses the debate; includes failing to state, repeating, forgetting, contradicting, using a fallacious reason, or being unable to answer a valid objection.

Nyaya Sutra lists 22 nigrahasthanas, e.g., pratijna-hani (dropping the thesis), pratijna-virodha (contradicting the thesis), hetvabhasa (fallacious reason), arthantara (irrelevant), nigraha-sthana (defeat).

The goal of vada is to arrive at nirnaya (settled truth); jalpa and vitanda are inferior forms used when the opponent is not sincere or when one seeks victory rather than truth.

A debater must avoid the defect of 'sadhyasama' (the reason being as unproved as the thesis) and must ensure the hetu is present in the paksha and absent in the vipaksha (where sadhya is absent).

Nyaya proves Ishvara (God) as the intelligent creator of the world, using inference: the world has a creator because it is an effect (karya) and effects have intelligent makers, like a pot.

Udayana's Nyaya Kusumanjali gives eight proofs for God's existence, including: (1) karyat (from effect), (2) ayojanat (from combination), (3) dhrtyat (from support), (4) padat (from word), (5) pratyayat (from cognition), (6) srutat (from scripture), (7) vakyat (from sentence), (8) sankhyat (from number).

Ishvara is omniscient (sarvajna), omnipotent (sarva-shaktiman), and the author of the Vedas; He is the efficient cause (nimitta-karana) of the world, not the material cause (upadana-karana).

Apavarga (liberation) is the cessation of suffering (dukha) and rebirth, attained through right knowledge (tattva-jnana) of the sixteen padarthas and the removal of false knowledge (mithya-jnana).

Nyaya's liberation is not a state of bliss but a state of absolute cessation of pain (dukha-nivrtti); the self (atma) remains as pure substance, without consciousness in the liberated state (according to some Nyaya thinkers).

The path: shravana (hearing), manana (reflection), nididhyasana (meditation) on the pramanas and padarthas; this leads to nirnaya and ultimately to apavarga.

Nyaya rejects the Advaita view of liberation as identity with Brahman; it maintains the plurality of selves and the reality of the world.

Dosha (defects) like attachment (raga) and aversion (dvesha) lead to karma and rebirth; right knowledge removes these doshas and thus stops the cycle of rebirth.

Ishvara is not a pramana but the object of inference and scripture; Nyaya's theism is inferential, not based on faith alone.

Gautama (Akshapada) authored the Nyaya Sutra (c. 2nd century CE or earlier), the foundational text with five adhyayas (chapters) containing 528 sutras.

Vatsyayana (Pakshilasvamin) wrote the Nyaya Bhasya (c. 4th–5th century CE), the earliest extant commentary on the Nyaya Sutra.

Udyotakara wrote the Nyaya Varttika (c. 6th century CE), defending Nyaya against Buddhist critiques (Dignaga, Dharmakirti).

Vacaspati Mishra wrote the Nyaya Varttika-tatparya-tika (c. 9th century CE), further clarifying the Nyaya position.

Udayana (c. 10th century CE) wrote the Nyaya Kusumanjali (proofs for God), Atma-tattva-viveka, and Nyaya-parishishta; he is a key figure in theistic Nyaya.

Jayanta Bhatta wrote the Nyaya Manjari (c. 9th century CE), a comprehensive exposition of Nyaya.

Gangesha Upadhyaya wrote the Tattva-cintamani (c. 12th–13th century CE), the foundational text of Navya-Nyaya, introducing a new technical language (e.g., vyapti, avacchedaka).

Navya-Nyaya developed in Mithila and Navadvipa (Bengal) with commentators like Vardhamana, Pakshadhara Mishra, Raghunatha Shiromani (Didhiti), and Gadadhara.

Other important texts: Bhasarvajna's Nyaya-sara, Annambhatta's Tarka-samgraha (a primer on Nyaya-Vaisheshika), and Visvanatha's Nyaya-siddhanta-muktavali.

Nyaya vs. Vaisheshika: Nyaya focuses on pramana (logic/epistemology), Vaisheshika on padartha (ontology); they merged into a syncretic school (Nyaya-Vaisheshika) sharing the seven padarthas of Vaisheshika (dravya, guna, karma, samanya, vishesha, samavaya, abhava).

Nyaya vs. Samkhya: Nyaya accepts a plurality of selves and Ishvara; Samkhya posits purusha (many) and prakrti (one), and is atheistic (or non-theistic); Nyaya's pramanas include shabda, while Samkhya accepts three pramanas (pratyaksha, anumana, shabda).

Nyaya vs. Yoga: Yoga accepts Ishvara but emphasizes practical discipline (yoga) for liberation; Nyaya emphasizes knowledge (jnana) and logic; both accept Ishvara and the plurality of selves.

Nyaya vs. Mimamsa: Mimamsa emphasizes ritual (karma-kanda) and the authority of the Vedas; it accepts pramana-vyavastha (each pramana has its own domain) and rejects Ishvara as a creator; Nyaya accepts Ishvara and pramana-samplava.

Nyaya vs. Vedanta (Advaita): Advaita holds non-dualism (Brahman alone real), rejects the plurality of selves, and considers the world as maya; Nyaya is pluralistic (many selves, real world) and theistic.

Nyaya vs. Buddhist schools: Nyaya rejects the Buddhist momentariness (kshanika) and the doctrine of no-self (anatman); it accepts the reality of universals (jati) and the validity of savikalpaka perception, which Buddhists deny.

Nyaya vs. Carvaka: Carvaka is materialistic and accepts only pratyaksha as pramana; Nyaya accepts four pramanas and refutes Carvaka's denial of inference and the self.

Nyaya's theory of error (anyatha-khyati) differs from Advaita's anirvacaniya-khyati and Buddhist asat-khyati; Nyaya holds that error involves a real object misapprehended, not an illusory object.

Nyaya's inference (five-membered) differs from Buddhist two-membered inference (hetu and sadhya) and from Advaita's three-membered (pratijna, hetu, drishtanta).