(

Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...

: न्याय, ''nyā-yá''), literally meaning "justice", "rules", "method" or "judgment",Nyaya: Indian Philosophy
Encyclopædia Britannica (2014) is one of the six '' astika'' schools of

Indian philosophy Indian philosophy refers to philosophical traditions of the Indian subcontinent. A traditional Hindu classification divides āstika and nāstika schools of philosophy, depending on one of three alternate criteria: whether it believes the Veda ...

. This school's most significant contributions to Indian philosophy were systematic development of the theory of

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premise ...

, methodology, and its treatises on epistemology.

Ancient Mithila University Ancient Mithila University was an Indian historical university famous for Nyaya Shastra and logical sciences. Background Gurukuls of the Vedic period in India can be called the ancient form of university because they had a system of higher ...

was famous for Nyaya Shastra teaching. Nyaya school's

epistemology Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics. Epis ...

accepts four out of six ''

Pramana ''Pramana'' (Sanskrit: प्रमाण, ) literally means "proof" and "means of knowledge".Gavin Flood __NOTOC__ Gavin Dennis Flood (born 1954) is a British scholar of comparative religion specialising in Shaivism and phenomenology, but with research interests that span South Asian traditions. From October 2005 through December 2015, he served ...

, An Introduction to Hinduism, Cambridge University Press, , page 225 In its

metaphysics Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...

, Nyaya school is closer to the

Vaisheshika Vaisheshika or Vaiśeṣika ( sa, वैशेषिक) is one of the six schools of Indian philosophy (Vedic systems) from ancient India. In its early stages, the Vaiśeṣika was an independent philosophy with its own metaphysics, epistemolog ...

school of Hinduism than others. It holds that human suffering results from mistakes/defects produced by activity under wrong knowledge (notions and ignorance). Moksha (liberation), it states, is gained through right knowledge. This premise led Nyaya to concern itself with epistemology, that is the reliable means to gain correct knowledge and to remove wrong notions. False knowledge is not merely ignorance to Naiyyayikas, it includes delusion. Correct knowledge is discovering and overcoming one's delusions, and understanding true nature of soul, self and reality. Naiyyayika scholars approached philosophy as a form of direct

realism Realism, Realistic, or Realists may refer to: In the arts *Realism (arts), the general attempt to depict subjects truthfully in different forms of the arts Arts movements related to realism include: *Classical Realism *Literary realism, a move ...

, stating that anything that really exists is in principle humanly knowable. To them, correct knowledge and understanding is different from simple, reflexive cognition; it requires '' Anuvyavasaya'' (अनुव्यवसाय, cross-examination of cognition, reflective cognition of what one thinks one knows). An influential collection of texts on logic and reason is the ''

Nyāya Sūtras The ''Nyāya Sūtras'' is an ancient Indian Sanskrit text composed by , and the foundational text of the Nyaya school of Hindu philosophy. The date when the text was composed, and the biography of its author is unknown, but variously esti ...

'', attributed to Aksapada Gautama, variously estimated to have been composed between 6th-century BCE and 2nd-century CE.Jeaneane Fowler (2002), Perspectives of Reality: An Introduction to the Philosophy of Hinduism, Sussex Academic Press, , page 129B. K. Matilal "Perception. An Essay on Classical Indian Theories of Knowledge" (Oxford University Press, 1986), p. xiv. Nyaya school shares some of its methodology and human suffering foundations with

Buddhism Buddhism ( , ), also known as Buddha Dharma and Dharmavinaya (), is an Indian religions, Indian religion or Indian philosophy#Buddhist philosophy, philosophical tradition based on Pre-sectarian Buddhism, teachings attributed to the Buddha. ...

; however, a key difference between the two is that Buddhism believes that there is neither a soul nor self; Nyaya school like other schools of Hinduism believes that there is a soul and self, with liberation (moksha) as a state of removal of ignorance, wrong knowledge, the gain of correct knowledge and unimpeded continuation of self. BK Matilal (1997), Logic, Language and Reality: Indian Philosophy and Contemporary Issues, Motilal Banarsidass, , pages 354-355

Etymology

''Nyaya'' (न्याय) is a Sanskrit word which means justice, equality for all being, specially a collection of general or universal rules. In some contexts, it means model, axiom, plan, legal proceeding, judicial sentence, or judgment. Nyaya could also mean, "that which shows the way" tracing its Sanskrit etymology. In the theory of logic, and Indian texts discussing it, the term also refers to an argument consisting of an

enthymeme An enthymeme ( el, ἐνθύμημα, ''enthýmēma'') is a form of rational appeal, or deductive argument. It is also known as a rhetorical syllogism and is used in oratorical practice. While the syllogism is used in dialectic, or the art of log ...

or sometimes for any syllogism.nyAya
Monier-Williams' Sanskrit-English Dictionary, Cologne Digital Sanskrit Lexicon, Germany In philosophical context, ''Nyaya'' encompasses propriety, logic and method. Panini, revered Sanskrit grammarian, derives the "Nyaya" from the root "i" which conveys the same meaning as "gam" - to go. "Nyaya" signifying logic is there etymologically identical with "nigama" the conclusion of a syllogism.The Nyaya Sutras of Gautama (Original Text, English Translation & Commentary) Translated & English Commentary by M.M. Satisa Candra Vidyabhusana Edited with a Sanskrit Preface by Dr. Sukhram ''Nyaya'' is related to several other concepts and words used in Indian philosophies: ''Hetu-vidya'' (science of causes), ''

Anviksiki Ānvīkṣikī is a term in Sanskrit denoting roughly the "science of inquiry" and it should have been recognized in India as a distinct branch of learning as early as 650 BCE. However, over the centuries its meaning and import have undergone con ...

'' (science of inquiry, systematic philosophy), ''Pramana-sastra'' (epistemology, science of correct knowledge), ''Tattva-sastra'' (science of categories), ''Tarka-vidya'' (science of reasoning, innovation, synthesis), ''Vadartha'' (science of discussion) and ''Phakkika-sastra'' (science of uncovering sophism, fraud, error, finding fakes). Some of these subsume or deploy the tools of ''Nyaya''.

Overview

The Nyaya of logic is said to have been founded by a sage named Gautama. He is also known as Gautama, Aksapada and Dirghatapas.The names Gotama and Gautama points to the family to which he belonged while the names Aksapada and Dirghatapas refer respectively to his meditative habit and practice of long penance. The people of Mithila (modern Darbhanga in North Bihar) ascribe the foundation of Nyaya philosophy to Gautama, husband of Ahalya, and point out as the place of his birth a village named Gautamasthana where a fair is held every year on the 9th day of the lunar month of

Chaitra Chaitra (Hindi: चैत्र) is a month of the Hindu calendar. In the standard Hindu calendar and India's national civil calendar, Chaitra is the first month of the year. It is the last month in the Bengali calendar, where it is called Cho ...

(March-April). It is situated 28 miles north-east of Darbhanga. The historical development of Nyaya school is unclear, although '' Nasadiya'' hymns of Book 10 Chapter 129 of

Rigveda The ''Rigveda'' or ''Rig Veda'' ( ', from ' "praise" and ' "knowledge") is an ancient Indian collection of Vedic Sanskrit hymns (''sūktas''). It is one of the four sacred canonical Hindu texts ('' śruti'') known as the Vedas. Only one ...

recite its spiritual questions in logical propositions. In early centuries BCE, states Clooney, the early Nyaya scholars began compiling the science of rational, coherent inquiry and pursuit of knowledge.Francis X. Clooney (2010), Hindu God, Christian God: How Reason Helps Break Down the Boundaries, Oxford University Press, , pages 18-19, 35-39 By 2nd century CE, Aksapada Gautama had composed ''Nyāya Sūtras'', a foundational text for Nyaya school, that primarily discusses logic, methodology and epistemology. The Nyaya scholars that followed refined it, expanded it, and applied it to spiritual questions. While the early Nyaya scholars published little to no analysis on whether supernatural power or God exists, they did apply their insights into reason and reliable means to knowledge to the questions of nature of existence, spirituality, happiness and

moksha ''Moksha'' (; sa, मोक्ष, '), also called ''vimoksha'', ''vimukti'' and ''mukti'', is a term in Hinduism, Buddhism, Jainism and Sikhism for various forms of emancipation, enlightenment, liberation, and release. In its soteriologic ...

. Later Nyaya scholars, such as

Udayana Udayana, ( Devanagari: उदयन) also known as Udayanācārya (Udyanacharya, or Master Udayana), (circa 975 - 1050 CE) was an Indian philosopher and logician of the tenth century of the Nyaya school who attempted to devise a rational theo ...

, examined various arguments on theism and attempted to prove existence of God. Other Nyaya scholars offered arguments to disprove the existence of God. The most important contribution made by the Nyaya school to Hindu thought has been its treatises on

and system of logic that, subsequently, has been adopted by the majority of the other Indian schools.Oliver Leaman (2006), Nyaya, in ''Encyclopaedia of Asian Philosophy'', Routledge, , pages 405-407

Sixteen categories (''padārthas'')

The Nyaya metaphysics recognizes sixteen '' padarthas'' or categories ''

Type theory In mathematics, logic, and computer science, a type theory is the formal presentation of a specific type system, and in general type theory is the academic study of type systems. Some type theories serve as alternatives to set theory as a fou ...

'' and includes all six (or seven) categories of the

in the second one of them, called ''prameya''. These sixteen categories are: #''pramāṇa'' (valid means of knowledgeor knowledge sources), #''prameya'' (objects of valid knowledge), #''saṁśaya'' (doubt), #''prayojana'' (aim), #''dṛṣṭānta'' (example), #''siddhānta'' (conclusion or accepted position), #''avayava'' (members of syllogism or inferential components), #''tarka'' (hypothetical/suppositional reasoning), #''nirṇaya'' (settlement or certainity), #''vāda'' (discussion or debate for truth), #''jalpa'' (wrangling or disputation), #''vitaṇḍā'' (cavilling or destructive debate), #''hetvābhāsa'' (fallacy or pseudo-proovers), #''chala'' (quibbling or equivocation), #''jāti'' (sophisticated refutation or misleading/futile objections) and #''nigrahasthāna'' (point of defeat or clinchers).Chattopadhyaya, D. (1986), ''Indian Philosophy: A Popular Introduction'', People's Publishing House, New Delhi, , p.163 According to Matthew Dasti and Stephen Phillips, it may be useful to interpret the word ''jnana'' as cognition rather than knowledge when studying the Nyaya system.

Epistemology

The Nyaya school of Hinduism developed and refined many treatises on

that widely influenced other schools of Hinduism. Nyaya treated it as theory of knowledge, and its scholars developed it as ''

Pramana ''Pramana'' (Sanskrit: प्रमाण, ) literally means "proof" and "means of knowledge".James Lochtefeld, "Pramana" in The Illustrated Encyclopedia of Hinduism, Vol. 2: N-Z, Rosen Publishing. , pages 520-521 The focus of Pramana is how correct knowledge can be acquired, how one knows, how one doesn't, and to what extent knowledge pertinent about someone or something can be acquired.Karl Potter (2002), Presuppositions of India's Philosophies, Motilal Banarsidass, , pages 25-26 The Naiyayikas (the Nyaya scholars) accepted four valid means (''pramaṇa'') of obtaining valid knowledge (''pramana'') - perception (''pratyakṣa''), inference (''anumāna''), comparison ('' upamāna'') and word/testimony of reliable sources (''śabda''). The Nyaya scholars, along with those from other schools of Hinduism, also developed a theory of error, to methodically establish means to identify errors and the process by which errors are made in human pursuit of knowledge. These include ''Saṁśaya'' (समस्या, problems, inconsistencies, doubts) and ''Viparyaya'' (विपर्यय, contrariness, errors) which can be corrected or resolved by a systematic process of ''Tarka'' (तर्क, reasoning, technique).

''Pratyaksha'' (perception)

''Pratyakṣa'' (perception) occupies the foremost position in the Nyaya epistemology. Perception can be of two types, ''laukika'' (ordinary) and ''alaukika'' (extraordinary).Troy Organ, Philosophy and the Self: East and West, Associated University Presse, , pages 91-94 Ordinary perception is defined by Akṣapāda Gautama in his ''Nyaya Sutra'' (I,i.4) as a 'non-erroneous cognition which is produced by the intercourse of sense-organs with the objects'. Indian texts identify four requirements for correct perception: ''Indriyarthasannikarsa'' (direct experience by one's sensory organ(s) with the object, whatever is being studied), ''Avyapadesya'' (non-verbal; correct perception is not through

hearsay Hearsay evidence, in a legal forum, is testimony from an under-oath witness who is reciting an out-of-court statement, the content of which is being offered to prove the truth of the matter asserted. In most courts, hearsay evidence is inadmiss ...

, according to ancient Indian scholars, where one's sensory organ relies on accepting or rejecting someone else's perception), ''Avyabhicara'' (does not wander; correct perception does not change, nor is it the result of deception because one's sensory organ or means of observation is drifting, defective, suspect) and ''Vyavasayatmaka'' (definite; correct perception excludes judgments of doubt, either because of one's failure to observe all the details, or because one is mixing inference with observation and observing what one wants to observe, or not observing what one does not want to observe).Karl Potter (1977), Meaning and Truth, in Encyclopedia of Indian Philosophies, Volume 2, Princeton University Press, Reprinted in 1995 by Motilal Banarsidass, , pages 160-168 Ordinary perception to Nyaya scholars was based on direct experience of reality by eyes, ears, nose, touch and taste. Extraordinary perception included ''yogaja'' or ''pratibha'' (intuition), ''samanyalaksanapratyaksa'' (a form of induction from perceived specifics to a universal), and ''jnanalaksanapratyaksa'' (a form of perception of prior processes and previous states of a 'topic of study' by observing its current state).

Determinate and indeterminate perception

The Naiyyayika maintains two modes or stages in perception. The first is called ''

nirvikalpa ''Samadhi'' (Pali and sa, समाधि), in Buddhism, Hinduism, Jainism, Sikhism and yogic schools, is a state of meditative consciousness. In Buddhism, it is the last of the eight elements of the Noble Eightfold Path. In the Ashtanga Yoga ...

'' (indeterminate), when one just perceives an object without being able to know its features, and the second '' savikalpa'' (determinate), when one is able to clearly know an object. All laukika and alaukika pratyakshas are ''savikalpa'', but it is necessarily preceded by an earlier stage when it is indeterminate. Vātsāyana says that if an object is perceived with its name we have determinate perception but if it is perceived without a name, we have indeterminate perception.

Jayanta Bhatta Jayanta Bhatta ( CE – CE) was a Kashmiri poet, teacher, logician, and an advisor to King Sankaravarman. He was a philosopher of the Nyaya school of Hindu philosophy. He authored three works on Nyāya philosophy: one of which is not known ...

says that indeterminate perception apprehends substance, qualities and actions and universals as separate and indistinct, without any association with any names, whereas determinate perception apprehends them all together with a name. There is yet another stage called ''Pratyabhijñā'', when one is able to re-recognise something on the basis of memory.C Sharma, A Critical Survey of Indian Philosophy, Delhi: Motilal Banarsidass, , pages192-196

''Anumāna'' (inference)

''Anumāna'' (inference) is one of the most important contributions of the Nyaya. It can be of two types: inference for oneself (''Svarthanumana'', where one does not need any formal procedure, and at the most the last three of their 5 steps), and inference for others (''Parathanumana'', which requires a systematic methodology of 5 steps). Inference can also be classified into 3 types: ''Purvavat'' (inferring an unperceived effect from a perceived cause), ''Sheshavat'' (inferring an unperceived cause from a perceived effect) and ''Samanyatodrishta'' (when inference is not based on causation but on uniformity of co-existence). A detailed analysis of error is also given, explaining when anumana could be false.

Theory of inference

The methodology of inference involves a combination of induction and deduction by moving from particular to particular via generality. It has five steps, as in the example shown: * There is fire on the hill (called ''Pratijñā'', required to be proved) * Because there is smoke there (called ''Hetu'', reason) * Wherever there is smoke, there is fire, e.g. in a kitchen (called ''Udāhārana'', example of vyāpti) * The hill has smoke that is pervaded by fire (called ''Upanaya'', reaffirmation or application) * Therefore, there is fire on the hill (called ''Nigamana'', conclusion) In Nyāya terminology for this example, the hill would be called as ''paksha'' (minor term), the fire is called as ''sādhya'' (major term), the smoke is called as ''hetu'', and the relationship between the smoke and the fire is called as ''

vyapti a Sanskrit expression, in Hindu philosophy refers to the state of pervasion. It is considered as the logical ground of inference which is one of the means to knowledge. No conclusion can be inferred without the knowledge of vyapti. Vyapti guarant ...

''(middle term). Hetu further has five characteristics * It must be present in the ''Paksha'' (the case under consideration), * It must be present in all positive instances (''sapaksha'', or homologues), * It must be absent in all negative instances * It must not incompatible with an established truth, (''abādhitatva'') * Absence of another evidence for the opposite thesis (''asatpratipakshitva'') The fallacies in Anumana (''hetvābhasa'') may occur due to the following #''Asiddha'': It is the unproved ''hetu'' that results in this fallacy. #*''Ashrayasiddha'': If Paksha inor termitself is unreal, then there cannot be locus of the hetu. e.g. The sky-lotus is fragrant, because it is a lotus like any other lotus. #*''Svarupasiddha'': Hetu cannot exist in paksa at all. E.g. Sound is a quality, because it is visible. #*''Vyapyatvasiddha'': Conditional hetu. `Wherever there is fire, there is smoke'. The presence of smoke is due to wet fuel. #''Savyabhichara'': This is the fallacy of irregular hetu. #*''Sadharana'': The hetu is too wide. It is present in both sapaksa and vipaksa. `The hill has fire because it is knowable'. #*''Asadharana'': The hetu is too narrow. It is only present in the Paksha, it is not present in the Sapaksa and in the Vipaksha. `Sound is eternal because it is audible'. #*''Anupasamhari'': Here the hetu is non-exclusive. The hetu is all-inclusive and leaves nothing by way of sapaksha or vipaksha. e.g. 'All things are non-ternal, because they are knowable'. #''Satpratipaksa'': Here the hetu is contradicted by another hetu. If both have equal force, then nothing follows. 'Sound is eternal, because it is audible', and 'Sound is non-eternal, because it is produced'. Here 'audible' is counterbalanced by 'produced' and both are of equal force. #''Badhita'': When another proof (as by perception) definitely contradicts and disproves the middle term (hetu). 'Fire is cold because it is a substance'. #''Viruddha'': Instead of proving something it is proving the opposite. 'Sound is eternal because it is produced'.

''Upamāna'' (comparison, analogy)

''Upamāna'' (उपमान) means comparison and analogy. ''Upamana'', states Lochtefeld, may be explained with the example of a traveller who has never visited lands or islands with endemic population of wildlife. He or she is told, by someone who has been there, that in those lands you see an animal that sort of looks like a cow, grazes like cow but is different from a cow in such and such way. Such use of analogy and comparison is, state the Indian epistemologists, a valid means of conditional knowledge, as it helps the traveller identify the new animal later.James Lochtefeld, "Upamana" in The Illustrated Encyclopedia of Hinduism, Vol. 2: N-Z, Rosen Publishing. , page 721 The subject of comparison is formally called ''upameyam'', the object of comparison is called ''upamānam'', while the attribute(s) are identified as ''sāmānya''.Monier Williams (1893), Indian Wisdom - Religious, Philosophical and Ethical Doctrines of the Hindus, Luzac & Co, London, pages 457-458 Thus, explains

Monier Williams Sir Monier Monier-Williams (; né Williams; 12 November 1819 – 11 April 1899) was a British scholar who was the second Boden Professor of Sanskrit at Oxford University, England. He studied, documented and taught Asian languages, especially ...

, if a boy says "her face is like the moon in charmingness", "her face" is ''upameyam'', the moon is ''upamānam'', and charmingness is ''sāmānya''. The 7th century text

Bhaṭṭikāvya ' (; "Bhatti's Poem") is a Sanskrit-language poem dating from the 7th century CE, in the formal genre of "great poem" (mahākāvya). It focuses on two deeply rooted Sanskrit traditions, the ''Ramayana'' and Panini's grammar, while incorporating nu ...

in verses 10.28 through 10.63 discusses many types of comparisons and analogies, identifying when this epistemic method is more useful and reliable, and when it is not. In various ancient and medieval texts of Hinduism, 32 types of ''Upamāna'' and their value in epistemology are debated.

''Śabda'' (word, testimony)

''Śabda'' (शब्द) means relying on word, testimony of past or present reliable experts. *Eliott Deutsche (2000), in Philosophy of Religion : Indian Philosophy Vol 4 (Editor: Roy Perrett), Routledge, , pages 245-248; *John A. Grimes, A Concise Dictionary of Indian Philosophy: Sanskrit Terms Defined in English, State University of New York Press, , page 238 Hiriyanna explains ''Sabda-pramana'' as a concept which means testimony of a reliable and trustworthy person (''āptavākya''). The schools of Hinduism which consider it epistemically valid suggest that a human being needs to know numerous facts, and with the limited time and energy available, he can learn only a fraction of those facts and truths directly.M. Hiriyanna (2000), The Essentials of Indian Philosophy, Motilal Banarsidass, , page 43 He must rely on others, his parent, family, friends, teachers, ancestors and kindred members of society to rapidly acquire and share knowledge and thereby enrich each other's lives. This means of gaining proper knowledge is either spoken or written, but through ''Sabda'' (words). The reliability of the source is important, and legitimate knowledge can only come from the ''Sabda'' of reliable sources. The disagreement between the schools of Hinduism has been on how to establish reliability. Some schools, such as

Carvaka Charvaka ( sa, चार्वाक; IAST: ''Cārvāka''), also known as ''Lokāyata'', is an ancient school of Indian materialism. Charvaka holds direct perception, empiricism, and conditional inference as proper sources of knowledge, embrace ...

, state that this is never possible, and therefore ''Sabda'' is not a proper pramana. Other schools debate means to establish reliability. Testimony can be of two types, ''Vaidika'' (

Vedic upright=1.2, The Vedas are ancient Sanskrit texts of Hinduism. Above: A page from the '' Atharvaveda''. The Vedas (, , ) are a large body of religious texts originating in ancient India. Composed in Vedic Sanskrit, the texts constitute the ...

), which are the words of the four sacred Vedas, and ''Laukika'', or words and writings of trustworthy human beings. ''Vaidika'' testimony is preferred over ''Laukika'' testimony. Laukika-sourced knowledge must be questioned and revised as more trustworthy knowledge becomes available.

Comparison with other schools of Hinduism

Each school of Hinduism has its own treatises on epistemology, with different number of ''

Pramana ''Pramana'' (Sanskrit: प्रमाण, ) literally means "proof" and "means of knowledge".Carvaka Charvaka ( sa, चार्वाक; IAST: ''Cārvāka''), also known as ''Lokāyata'', is an ancient school of Indian materialism. Charvaka holds direct perception, empiricism, and conditional inference as proper sources of knowledge, embrace ...

school has just one (perception), while

Advaita Vedanta ''Advaita Vedanta'' (; sa, अद्वैत वेदान्त, ) is a Hindu sādhanā, a path of spiritual discipline and experience, and the oldest extant tradition of the orthodox Hindu school Vedānta. The term ''Advaita'' ( ...

school recognizes six means to reliable knowledge.

Theory of causation

A ''cause'' is defined as an unconditional and invariable antecedent of an ''effect'' and an effect as an unconditional and invariable consequent of a cause. The same cause produces the same effect; and the same effect is produced by the same cause. The cause is ''not'' present in any hidden form whatsoever in its effect. The following conditions should be met: # The cause must be antecedent urvavrtti# Invariability iyatapurvavrtti# Unconditionality nanyathasiddha Nyaya recognizes five kinds of accidental antecedents nyathasiddha # Mere accidental antecedent. E.g., The colour of the potter's cloth. # Remote cause is not a cause because it is not unconditional. E.g., The father of the potter. # The co-effects of a cause are not causally related. # Eternal substances, or eternal conditions are not unconditional antecedents, e.g. space. # Unnecessary things, e.g. the donkey of the potter. Nyaya recognizes three kinds of cause: # ''Samavayi'', material cause, e.g. thread of a cloth. # ''Asamavayi'', colour of the thread which gives the colour of the cloth. # ''Nimitta'', efficient cause, e.g. the weaver of the cloth.

''Anyathakhyativada'' (theory of error)

The Nyaya theory of error is similar to that of Kumarila's Viparita-khyati (see Mimamsa). The Naiyyayikas also believe like Kumarila that error is due to a wrong synthesis of the presented and the represented objects. The represented object is confused with the presented one. The word 'anyatha' means 'elsewise' and 'elsewhere' and both these meanings are brought out in error. The presented object is perceived elsewise and the represented object exists elsewhere. They further maintain that knowledge is not intrinsically valid but becomes so on account of extraneous conditions (''paratah pramana'' during both validity and invalidity).

On God and salvation

Early Naiyyayikas wrote very little about

Ishvara ''Ishvara'' () is a concept in Hinduism, with a wide range of meanings that depend on the era and the school of Hinduism. Monier Monier Williams, Sanskrit-English dictionarySearch for Izvara University of Cologne, Germany In ancient texts of ...

(literally, the Supreme Soul). Evidence available so far suggests that early Nyaya scholars were non-theistic or atheists. Later, and over time, Nyaya scholars tried to apply some of their epistemological insights and methodology to the question: does God exist? Some offered arguments against and some in favor.

Arguments that God does not exist

In Nyāya Sūtra's Book 4, Chapter 1, verses 19–21, postulates God exists, states a consequence, then presents contrary evidence, and from contradiction concludes that the postulate must be invalid. A literal interpretation of the three verses suggests that Nyaya school rejected the need for a God for the efficacy of human activity. Since human action and results do not require assumption or need of the existence of God, sutra IV.1.21 is seen as a criticism of the "existence of God and theism postulate". The context of the above verses includes various efficient causes. Nyāya Sūtra verses IV.1.22 to IV.1.24, for example, examine the hypothesis that "random chance" explains the world, after these Indian scholars had rejected God as the efficient cause.

Arguments that God exists

's '' Nyayakusumanjali'' gave the following nine arguments to prove the existence of creative God and also tried to refute the existing objections and questions by atheistic systems of charvaka, mimamsa, buddhists, jains and samkhya:Sharma, C. (1997). ''A Critical Survey of Indian Philosophy'', Delhi: Motilal Banarsidass, , pp.209-10 *''Kāryāt'' (lit. "from effect"): The world is an effect, all effects have efficient cause, hence the world must have an efficient cause. That efficient cause is God. *''Āyojanāt'' (lit., from combination): Atoms are inactive. To form a substance, they must combine. To combine, they must move. Nothing moves without intelligence and source of motion. Since we perceive substance, some intelligent source must have moved the inactive atoms. That intelligent source is God. *''Dhŗtyādéḥ'' (lit., from support): Something sustains this world. Something destroys this world. Unintelligent ''Adrsta'' (unseen principles of nature) cannot do this. We must infer that something intelligent is behind. That is God. *''Padāt'' (lit., from word): Each word has meaning and represents an object. This representational power of words has a cause. That cause is God. *''Pratyayataḥ'' (lit, from faith): Vedas are infallible. Human beings are fallible. Infallible Vedas cannot have been authored by fallible human beings. Someone authored the infallible Vedas. That author is God. *''Shrutéḥ'' (lit., from scriptures): The infallible Vedas testify to the existence of God. Thus God exists. *''Vākyāt'' (lit., from precepts): Vedas deal with moral laws, the rights and the wrongs. These are divine. Divine injunctions and prohibitions can only come from a divine creator of laws. That divine creator is God. *''Samkhyāviśeşāt'' (lit., from the specialty of numbers): By rules of perception, only number "one" can ever be directly perceived. All other numbers other than one, are inferences and concepts created by consciousness. When man is born, his mind is incapable of inferences and concepts. He develops consciousness as he develops. The consciousness development is self-evident and proven because of man's ability with perfect numerical conception. This ability to conceive numerically perfect concepts must depend on something. That something is divine consciousness. So God must exist. *''Adŗşţāt'' (lit., from the unforeseen): Everybody reaps the fruits of his own actions. Merits and demerits accrue from his own actions. An Unseen Power keeps a balance sheet of the merit and demerit. But since this Unseen Power is Unintelligent, it needs intelligent guidance to work. That intelligent guide is God.

Liberation

The Naiyyayikas believe that the bondage of the world is due to false knowledge, which can be removed by constantly thinking of its opposite (''pratipakshabhavana''), namely, the true knowledge. So the opening aphorism of the ' states that only the true knowledge lead to ''niḥśreyasa'' (liberation). But the Nyaya school also maintains that the God's grace is essential for obtaining true knowledge.

Jayanta Jayanta ( sa, जयन्त, "victory"), is a character who appears in Hindu literature. He is the son of Indra, the king of the devas (gods), and his wife, Shachi (Indrani). He has a sister called Jayanti. He appears in various Hindu scri ...

, in his ''Nyayamanjari'' describes salvation as a passive stage of self in its natural purity, unassociated with pleasure, pain, knowledge and willingness.

Literature

The earliest text of the Nyāya School is the ' of . The text is divided into five books, each having two sections. 's ' is a classic commentary on the '. Udyotakara's ' (6th century CE) is written to defend against the attacks made by

Dignāga Dignāga (a.k.a. ''Diṅnāga'', c. 480 – c. 540 CE) was an Indian Buddhist scholar and one of the Buddhist founders of Indian logic (''hetu vidyā''). Dignāga's work laid the groundwork for the development of deductive logic in India and ...

. 's ' (9th century CE) is the next major exposition of this school. Two other texts, ' and ' are also attributed to him.

's (984 CE) ' is an important commentary on 's treatise. His ' is the first systematic account of theistic '. His other works include ', ' and '.

's ' (10th century CE) is basically an independent work. 's ' (10th century CE) is a survey of ' philosophy. The later works on ' accepted the '' '' categories and 's ' (12th century CE) is a notable treatise of this syncretist school. 's ' (13th century CE) is another important work of this school. 's ' (14th century CE) is the first major treatise of the new school of '. His son, 's ', though a commentary on

's ', incorporated his father's views. Jayadeva wrote a commentary on '' '' known as ' (14th century CE). 's ' (16th century CE) is first great work of

Navadvipa Nabadwip (), also spelt Navadwip, anciently Nadia or Nudiya, is a heritage city in Nadia district in the Indian state of West Bengal. It is regarded as a holy place by Hindus, and is the birthplace of Chaitanya Mahaprabhu. Famous for Rass fest ...

school of . 's ' and ' are the next important works of this school. 's ' (17th century CE) is also a notable work.Radhakrishnan, S. ''Indian Philosophy'', Vol. II, Oxford University Press, New Delhi, 2006, , p.41 The Commentaries on ' by Jagadish Tarkalankar (17th century CE) and Gadadhar Bhattacharya (17th century CE) are the last two notable works of this school. (17th century CE) tried to develop a consistent system by combining the ancient and the new schools, ' and ' and ' to develop the ' school. His ' and ' are the popular manuals of this school.

Commentaries on the Nyaya-Sutra

Numerous commentaries have been written on Nyaya-Sutra since its composition. Some of these commentaries are available o
www.archive.org
for reference. A few of the commentaries are mentioned below: # Nyaya-Sutra by Gotama or Aksapada # Nyaya-Bhasya by Vatsyayana # Nyaya-Varttika by Udyotakara # Nyaya-Varttika tatparya-tika by Vacaspati Misra # Nyaya-Varttika-tatparayatika-parisuddhi by Udayans # Parisuddhiprakasa by Vardhamana # Vardhamanedu by Padmanabha Misra # Nyayalankara by Srikantha # Nyayalankara Vrtti by Jayanta # Nyaya-manjari by Jayanta # Nyaya-Vrtti by Abhayatilakopadhyaya # Nyaya-Vrtti by Visvanatha # Mitabhasini Vrtti by Mahadeva Vedanti # Nyayaprakasa by Kesava Misra # Nyayabodhini by Govardhana # Nyaya Sutra Vyakhya by Mathuranatha

Differences from Western logic

The essential features of logic in the Western tradition are well captured in the following statement by a famous logician

Alonzo Church Alonzo Church (June 14, 1903 – August 11, 1995) was an American mathematician, computer scientist, logician, philosopher, professor and editor who made major contributions to mathematical logic and the foundations of theoretical computer scien ...

: Thus, the basic features of Western logic are: It deals with a study of ‘propositions’, specially their ‘logical form’ as abstracted from their ‘content’ or ‘matter’. It deals with ‘general conditions of valid inference’, wherein the truth or otherwise of the premises have no bearing on the ‘logical soundness or validity’ of an inference. It achieves this by taking recourse to a symbolic language that has little to do with natural languages. The main concern of Western logic, in its entire course of development, has been one of systematising patterns of mathematical reasoning, with the mathematical objects being thought of as existing either in an independent ideal world or in a formal domain.

Indian logic The development of Indian logic dates back to the ''anviksiki'' of Medhatithi Gautama (c. 6th century BCE); the Sanskrit grammar rules of Pāṇini (c. 5th century BCE); the Vaisheshika school's analysis of atomism (c. 6th century BCE to 2nd centu ...

however, does not deal with ideal entities, such as propositions, logical truth as distinguished from material truth, or with purely symbolic languages that apparently have nothing to do with natural languages. The central concern of Indian logic as founded in Nyāya is epistemology, or the theory of knowledge. Thus Indian logic is not concerned merely with making arguments in formal mathematics rigorous and precise, but attends to the much larger issue of providing rigour to the arguments encountered in natural sciences (including mathematics, which in Indian tradition has the attributes of a natural science and not that of a collection of context free formal statements), and in philosophical discourse. Inference in Indian logic is ‘deductive and inductive’, ‘formal as well as material’. In essence, it is the method of scientific enquiry. Indian ‘formal logic’ is thus not ‘formal’, in the sense generally understood: in Indian logic ‘form’ cannot be entirely separated from ‘content’. In fact, great care is exercised to exclude from logical discourse terms, which have no referential content. No statement, which is known to be false, is admitted as a premise in a valid argument. Thus, the ‘method of indirect proof’ (

reductio ad absurdum In logic, (Latin for "reduction to absurdity"), also known as (Latin for "argument to absurdity") or ''apagogical arguments'', is the form of argument that attempts to establish a claim by showing that the opposite scenario would lead to absu ...

) is not accepted as a valid method−neither in Indian philosophy nor in Indian mathematics−for proving the existence of an entity whose existence is not demonstrable (even in principle) by other (direct) means of proof. Indian logic does not make any attempt to develop a purely symbolic and content independent or ‘formal language’ as the vehicle of logical analysis. Instead, what Indian logic, especially in its later phase of Navya-Nyāya starting with the work of Gāngeśa Upādhyāya of 14th century, has developed is a technical language, which is based on the natural language

, yet avoids ‘inexactness’ and ‘misleading irregularities’ by various technical devices. This technical language, being based on the natural language Sanskrit, inherits a certain natural structure and interpretation, and sensitivity to the context of enquiry. On the other hand, the symbolic formal systems of Western logic, though considerably influenced in their structure (say, in quantification, etc.) by the basic patterns discernible in European languages, are professedly purely symbolic, carrying no interpretation whatsoever−such interpretations are supposed to be supplied separately in the specific context of the particular field of enquiry ‘employing’ the symbolic formal system.

References

External links

* * *
Lectures on Nyaya
The Oxford Centre for Hindu Studies, Oxford University * Ganeri, Jonardon,

Edward N. Zalta Edward Nouri Zalta (; born March 16, 1952) is an American philosopher who is a senior research scholar at the Center for the Study of Language and Information at Stanford University. He received his BA at Rice University in 1975 and his PhD fro ...

(ed.)
"Analytic Philosophy in Early Modern India"
'' Stanford Encyclopedia of Philosophy.'' {{Logic, state=collapsed Movements in ancient Indian philosophy Atomism Hindu philosophy History of logic Āstika