Discussions, Debates and Arguments: Samvada–Vaada –Jalpa and Vitanda
In the Indian traditions, including the Buddhist and Jain traditions, four formats of discussions, debates and arguments are described. These are named as: Samvada, Vaada, Jalpa and Vitanda. The merit and esteem of each of these types of discussions is graded in terms of the honesty of their purpose, the quality of debate, the decorum and the mutual regard of the participants.
Of these four forms of discussions, Samvada is regarded the noblest type of dialogue that takes place, in all earnestness, between an ardent seeker of truth and an enlightened teacher. Most of the ancient Indian texts are in this format.
While Samvada is a discourse or imparting of teaching, the other three – Vaada, Jalpa and Vitanda – are clever and structured (Tantra–yukthi) debates and arguments between rivals.
Let’s talk of Nyaya (well-organized logical ways of ascertaining the true nature of the objects and subjects of human knowledge) and Samvada on one part; and, the debates/arguments on the other.
As is well known, there was a long and a time-honored tradition in ancient India where philosophers and thinkers met to discuss metaphysical issues over which there were multiple views. There are detailed narrations of such discussions, debates and dialogues recorded in Chandogya Upanishad, Brihadaranyaka Upanishad and Prashna Upanishad.
The other early texts such as Aitareya Brahmana , Kathopanishad and others use terms like : tarka (reasoning) , Vada (debate) , Yukti ( sustained arguments) , Prameya (object of knowledge) , Pramana (proof), Nirnaya (ascertainment) etc. which later became the principal terminologies of the Nyaya School. It is also said that the idioms of inquiry (Anveshiki) dealing with the theory of reasons (Hetu-vidya or Hetu-shastra) were mentioned in Manu-samhita and Panini’s Astadhyayi.
Although intellectual debates were quite common during the Upanishad-times, and even later, there was perhaps no well laid out theory or an approved structure for conduct of various types of debates. It is said; it was during the Sramana and the Buddhist period that debates became really very serious.
As Bimal Krishna Matilal observes (in The Character of Logic in India):
.. The intellectual climate in India was bristling with controversy and criticism. At the center of controversy were certain dominant religious and ethical issues. Nothing was too sacred for criticism. Such questions as: “Is there a soul different from body?”; “Is the world (loka) eternal?”; ”What is the meaning, goal, or purpose of life?”; and, “Is renunciation preferable to enjoyment?” etc. were of major concern. While teachers and thinkers argued about such matters, there arose a gradual awareness of the characteristics or patterns of correct, acceptable and sound reasoning. There were also concerns to evolve the norms to distinguish sound reasoning from pseudo-reasoning (hetvabhasa) which is unacceptable.
The debates tended to get more passionate, animated and even noisy. Gradually, the notions of ‘good’ and acceptable debates took shape as distinct from wrong and ugly arguments. That gave rise to the development of a branch of study dealing with theories of reasoning and logic (Hetu-vidya or Hetu shastra). It was perhaps around the fifth century BCE that manuals came to be written for conduct of proper and successful debates (Tarka vidya or Vada vidya). Such manuals included instructions and learning methods for the guidance of aspiring debaters. The earliest known text of that genre was Tantra-yukti (structured argument) compiled perhaps in the sixth-fifth century BCE to systemize debates conducted in learned councils (Parishad).
Debates and arguments then came to be recognized both as art of logical reasoning (Tarka-vidya) and science of causes (Hetu-shastra) following the path of a well-disciplined method of inquiry (ânvikŝiki) testing scriptural knowledge by further scrutiny.
The monks and priests belonging to various Schools and sects were imparted training in Tarka–vidya: the art and skills of conducting impressive successful debates and disputations (Sambasha or Vada vidhi) in learned assemblies (parishad). Apart from methods of presenting arguments as per a logically structured format, the training modules included ways to stoutly defend ones thesis by means of genuine criteria of knowledge (Pramana) and to attack the opponent’s thesis by means of indirect arguments (Tarka); estimating the strengths and weaknesses of arguments of either side; establishing one’s own points while setting aside those of the opponent. They were also trained for handling different types of challenges, such as: how to vanquish a person of blazing fame; how to behave with a senior opponent; how to handle an aggressive and troublesome opponent; and, how to conduct oneself in prestigious Parishads , to influence the flow of debate and to impress the judges and the onlookers etc.
These types of debates and arguments came under the purview of Nyaya or Nyaya Shastra.
Nyaya, as a system, is one among the six Darshanas (systems of Indian philosophy). It deals with well-organized logical ways of ascertaining the true nature of the objects and subjects of human knowledge (Pramana-Sastra). Nyaya is also called Tarka-vidya (logic) and Vada-vidya or Vada’rtha (reasoned argument); and is included among the fourteen principal branches of learning.
Nyaya is founded on the belief that knowledge is not self-revealing; man must make effort to gain correct knowledge and to abandon incorrect knowledge, through a systematic process. It asserts that the analytical way of Nyaya is the greatest protection to a young person whose intellect is still in the process of growth and is yet to attain equanimity. And, it is only by thorough examination of the modes and sources of correct knowledge that a thinking person can gain a clearer perspective of life. It asks each one to think for himself; and, not to tacitly accept beliefs handed down by the older generation. And, therefore, it instructs, the teachings that have come down to us through traditions must be critically examined before accepting them.
Vatsayana in his Nyāya Bhāṣya , a Commentary on Nyaya Sutra (1.1.1) , asserts that the analytical investigation and examination (Anveshiki) of issues which bring clarity into the intellectual aspects of man’s life help him to attain freedom (moksha) from delusions and confusions in life. Nyaya which enables us to discern the true from the false is therefore regarded as Moksha-Sadhana the way to absolute freedom or liberation.
Nyaya, in particular, also denotes a method or a scheme of logic employed to prove or to disprove a proposition through proper evidence (pramana). The employment of a Nyaya would become necessary when the subject discussed was either vague or was disputed; and when the other methods of reasoning were ineffective.
The Nyaya School was essentially logistic in its orientation. It tried to examine the sources and contents of valid knowledge. It built a logical link between the subject, the knower (pramata); the means or method of obtaining knowledge (pramana) ; and the object , the knowable (prameya) . In addition, it put forth analogy (Upama) as the fourth method. Analogy, it said, comprehensively included in itself the other three methods.
[ Prof. Surendranath Dasgupta explains in A History of Indian Philosophy, Volume 1 (p.406):
Pramana in Sanskrit signifies the means and movement by which knowledge is acquired Pramata means the subject or the knower who cognizes, Prama –the result of pramana i.e., right knowledge, knowledge of reality or valid cognition, prameya–the object of knowledge and pramanya – the validity of knowledge acquired. The verbal root ma of these terms derived with the prefix pra, means also to measure (apart from meaning to cognize.) Thus, what is to be measured is the prameya, and that by which to measure is pramana.]
[ In Sanskrit, the term Jnana stands for all kinds of knowledge – whether be it of truth or of falsehood. The term Prama, however, is used to designate only a true cognition (yatartha-jnana) as distinct from a false one (mithya-jnana). A Pramana is an active and a unique cause of Prama or knowledge. The Samkhya and Yoga Schools of Indian philosophy accept three means of cognition, Pramanas: Pratyakasha (direct perception) , Anumana (inference) and Sabda ( verbal testimony). The Mimamsa School accepts six types of Pramanas: Pratyaksha, Anumana, Sabda, Upamana (analogy), Arthapatti (presumption) and Abhava (non-apprehension). The same set of six Pramanas is also stated by Vedanta. There are, of course, variations among these Schools regarding the specific understang of each of the Pramans.
Within Vyakarana, Bhartrhari in his Maha-bhashya-tika accepts three Pramanas: Pratyasha (perception), Anumana (inference) and Agama or Sabda (scriptures). He argues that perception, at times, could be erranous because of weakness or improper functioning of sensory organs. Some even think, he says, that inference is superior to perception. But he asserts that Agama or Sabda which consists of the revealed (Sruti) or remembered (Smrti) scriptures is a strong Pramana; and, it is more dependable than inference.
According to Bhartrhari, it is not justifiable to replace scriptures (Sabda) with inference particularly in non- empirical matters. He also says that philosophical views (Vada) cannot be independent of the scriptures. He argues that inference alone, without the steadying influence of the scriptures is an inadequate means of valid knowledge. In his Vakyapadiya (1.34), it is said: ‘whatever is inferred with great effort through clever reasoning can easily be put aside by a much more clever reasoning or argument’.
yatnenānumito+apy arthaḥ kuśalair anumātṛbhiḥ / abhiyuktatarair anyair anyathaivopapādyate -VP.1.34
The words of the Rishis convey super-sensory knowledge that cannot be set aside by inference. Thus, Bhartrhari asserts that Dharma or right conduct cannot be determined by reasoning alone, without the guidance of the scriptural traditions. Even the knowledge which the sages possess has the scriptures for its reference (Vakyapadiya: 1.30). Thus, tor true knowledge, the support of the scriptures (Sabda) is essential.
na jāgamād ṛte dharmas tarkeṇa vyavatiṣṭhate / ṛṣīṇām api yaj jñānaṃ tad apy āgamapūrvakam – VP.1.30
In this context, Bharthari says that the role of Vyakarana (Grammar) is very important, as it helps to safeguard the correct transmission of the scriptural knowledge , and to assist the aspirant in realizing the the truth of the revealed knowledge of Sabda.]
The Sutra text attached to Nyaya School is the Nyaya Sutra ascribed to Akṣapāda Gautama (variously estimated between 6th-century BCE and 2nd-century CE). Nyaya Sutra treats mainly five subjects: Pramana (instruments or means of right knowledge); Prameya (the object of right knowledge); Vaada (debate or discussion); Avayava (the elements or steps of syllogism); and, Anya-matha-pariksha (review or examination of the doctrines of other Schools).
While discussing Vaada, Nyaya Sutra talks about sixteen padarthas (topics or categories ) involved in the development of the debate (Vada marga); the four reliable means of obtaining valid knowledge (pramāṇa) viz.:
Pratyaksha (perception), Anumana (inference), Upamana (comparison ) and Sabda (reliable testimony ); the five-part syllogism (Nyaya); the structure (vada vidhi); the ways of developing sound evidence (pramana); the logical reasoning (tarka) to support ones thesis which needs to be proved (Pratijna) and its object (nirnaya); the disciplined (anusasana) mode of presentation (vadopaya); and the exceptions (prthaka-prasthana), as also the limits or the ‘dos and don’ts’ (vada-maryada) of three formats of such debates.
(vāda-lakṣaṇam : pramāṇa-tarka-sādhanopālambhaḥ siddhāntā-viruddhaḥ pañcā-vayavopapannaḥ pakṣa-pratipakṣa-parigrahaḥ vādaḥ – 1.2.1)
Gautama’s text was followed by commentaries; the first of which being Nyāya Bhāṣya by Vātsyāyana (c. 450–500 CE). The commentary by Vatsayana was followed the ones by the Nyāya-vārttika of Uddyotakāra (c. 6th–7th century); Tātparya-tīkā by Vācaspati Miśra (9th century); Tātparya-pariśuddhi by Udayana (10th century); Nyāya-mañjarī by Jayanta (10th century); Nyaya-sara by Bhasarvajna (10th century); and Tatva-chintamani by Gangesa (12th century). These commentaries further developed the Nyaya Sutra expanding upon Gautama’s work.
As per these texts, the debates and arguments are grouped under a broad head titled ‘Katha’. In Sanskrit, the term ‘Katha’, in general, translates as ‘to inform’, ‘to narrate’, ‘to address or to refer to somebody’. In the context of Nyaya Shatra, which provides the knowledge (Vako-Vakya or Vada-vidya) about the methods for presenting arguments as also the rules governing the debates, the term ‘Katha’ implies formal conversation (Sambasha) as in a debate. The conversation here is not in the casual manner as in day-to-day life. But, it is articulate, precise and well thought out utterances. Katha is described as ‘polemical conversation’, meaning that it is passionate and strongly worded , but a well balanced argument against or in favor of somebody or something. That is why; the discussions (Vaada) are never simple. A Katha, in essence, is a reasoned and a well-structured philosophical discussion.
Vatsayana at the beginning of his commentary on Nyaya Sutra (1.2.1) mentions that Katha is classified into two kinds of debates (Dvi-vidha sambasha): Vaada (the good-Sandhya sambasha) on one hand; and Jalpa and Vitanda (the bad- Vigrahya sambasha) on the other. Uddyotakara in his Nyāya Vārttika further explains that this threefold classification is according to the nature of the debate and the status of the persons taking part in the debate.
(padārtha-uddeśa-sūtram:pramāṇa-prameya-saṃśaya-prayojana-dṛṣṭānta-siddhāntāvayava-tarka-nirṇaya-vāda-jalpa-vitaṇḍāhetvābhāsa-cchala-jāti-nigrahasthānānāmtattvajñānāt niḥśreyasādhigamaḥ- 1.1.1 )
The first variety , Vaada is an honest , peaceful and congenial (sandhaya) debate that takes place between two persons of equal merit or standing, trying to explore the various dimensions of a subject with a view to ascertain and establish ‘what is true’. The Vaada, at its best, is a candid friendly discussion (anuloma sambasha or sandhya sambasha) or debate in the spirit of: ’let’s sit-down and talk’.
The other two are hostile arguments (vigrhya sambasha) between rivals who desperately want to win. Thus, by implication, while the goal of a Vaada is establishment of truth or an accepted doctrine; and that of the other two hostile debates (Jalpa and Vitanda) is seeking victory.
Of the two types of hostile debates, Jalpa is described (in Nyaya Sutra 1.2.2) as a disputation or wrangling or a ’tricky’ debate between two rivals , where each is thoroughly convinced that he is absolutely right and the other (termed as the opponent – Prativadin) is hopelessly wrong. The first party to the debate is dogmatically committed to his own thesis, while the other party takes a rigid contrary position (Prati-paksha) on a given subject; and, sometimes at the cost of truth. Each is prepared to employ various deceptive or sophistic devices, such as quibbling (Chala); unreasonable (A-hetu) responses; shifting the reason or the topics ( Hetvantara or Arthantara); irrelevant rejoinders provoking the opponent to lose focus , to get perturbed and yet continue with the dispute (Jati) somehow; and , such other devices to outwit the opponent.
(jalpa-lakṣaṇam : yathoktopapannaḥ chalajātinigrahasthānasādhanopālambhaḥ jalpaḥ-1.2.2)
Unlike in Vaada, the purpose of Jalpa is not so much as to ascertain the truth, as to establish one’s own position or thesis, and to prove the opponent wrong; and, make him accept defeat. What is at stake here is the ‘prestige and honor’ of one’s School (Matha). And, therefore, each will try to win the debate by fair or foul means. And, when one senses that he might be losing the argument (nigrahasthāna), he will try to invent every sort of face-saving device or ruse to wriggle out of a bad situation that is quickly turning worse. Jalpa, predictably, could be noisy and unpleasant.
And, Vitanda is the worst type of argument or squabbling descending to the level of quarrel and trickery. It is described as a destructive type of argument; the sole aim of each party being not only to inflict defeat on the opponent but also to demolish and humiliate him . The Vaitandika , the debater who employs Vitanda, is basically a refuter; he relentlessly goes on refuting whatever the proponent says. He has no thesis of his own – either to put forward or to defend. Sometimes he might pick up a thesis just for argument’s sake, even though he may have no faith in the truth of his own argument. The aggressive Vaitandika goes on picking holes in the rival’s arguments and destabilises his position , without any attempt to offer an alternate thesis. Both the participants in a Vitanda are prepared to resort to mean tactics in order to mislead, browbeat the opponent by fallacies (hetv-abhasa); by attacking the opponents statement by willful misrepresentation (Chala) ; ill-timed rejoinders (Atita-kala) and, make the opponent ‘bite the dust’. It is virtually akin to a ‘no-holds-barred’ sort of street fight. The ethereal values such as: truth, honesty, mutual respect and such others are conspicuously absent here.
(vitaṇḍā-lakṣaṇam : saḥ pratipakṣa-sthāpanā-hīnaḥ vitaṇḍā -1.2.3)
It is said; in the case of Jalpa the contending parties have a position of their own, fight hard to defend it, and aim to make the rival accept it, by whatever means. However, in the Vitanda, the disputant has neither a position of his own nor is he trying to defend any specific thesis. He is merely trying to derange and humiliate the other party to the debate. Vatsayana in his Nyaya-sutra Bhashya calls one who resorts to Vitanda (Vaitandika) as self-destructive.
Even in the case of Jalpa and Vitanda, the disputants had to agree, beforehand, to certain rules, norms and devices, so that the defeat could be forced by the judge (Madyastha) on one or the other party.
A debate with the mere aim of win or humiliation of the other is looked down. Therefore, Jalpa and Vitanda are deemed contrary to the overall aim of the Nyaya Shastra which is oriented towards determination of the true nature of objects.
[The skills in waging debates and arguments (Vada-vidya) of the Jalpa and Vitanda might have been relevant during the medieval times when the inter–religious or intra-religious debates (Shastrartha) were held among the rival traditions (Sampradaya) or sects, each trying hard to prove the superiority of its Matha (thesis or sect) over the others. In the present context, such beliefs and arguments have become obsolete in India, though their techniques are very well preserved and practiced in Tibetan Buddhist debates.
Having said that , the syllogism, logical structure and methods of presenting reasoned arguments as described in the ancient texts are still of great interest. Its methodology based on a system of logic is the same for us today in our lecture halls and programming desks as it was for the medieval scholars.]
Let’s look at each of these types of discussions and arguments in a little more detail.
Samvada is a dialogue that takes between the teacher and the taught in all earnestness. The one who approaches the teacher could be a disciple; student; friend (as in Krishna-Arjuna or Krishna-Uddhava) ; son (as in Shiva-Skanda or Uddalaka-Swetaketu); or spouse (as in Shiva-Prvathi or Yajnavalkya-Maitreyi); or parent (as Sage Kapila teaching his mother); or anyone else seeking knowledge (as in Nachiketa -Yama or the six persons who approach Sage Pippalada in Prashna Upanishad). What characterizes the Samvada in such cases is the sincerity and eagerness of the learner; the humility in his/her approach; and the absolute trust in the teacher. The wise teacher , in turn , with full of grace , imparts instructions out of enormous love for the ardent seeker of truth.
(siddhānta-sūtra : jñāna-grahaṇā-abhyāsas tad-vidyaiśca saha saṃvādaḥ- 4.2.47)
vidhya-artha-vādā-anuvāda-vacanaviniyogāt ; vidhiḥ vidhāyakaḥ; stutiḥ nindā parakṛtiḥ purākalpaḥ iti arthavādaḥ ;na anuvādapunaruktayoḥ viśeṣaḥ, śabdābhyāsopapatteḥ ; śīghrataragamanopadeśavat abhyāsāt na aviśeṣaḥ; mantrāyurvedaprāmāṇyavat ca tatprāmāṇyam, āpta-prāmāṇyāt (2.1.63-69)
Samvada is thus a dialogue that teaches, imparts instructions or passes on knowledge.
The bulk of the Upanishad teachings have come down to us in the form of Samvada, which took place in varieties of contexts. Apart from intimate sessions where an illumined teacher imparts instructions to an aspirant , there are instances of varied kind, say, as when : a wife is curious to learn from her husband the secrets of immortality; a teenage boy approaches Death itself to learn the truth of life and death; a king seeks instruction from an recluse sage who speaks from his experience ; Brahmans advanced in age and wisdom sit at the feet of a Kshatriya prince seeking instructions as also inspiration ; and , when sometimes the sages are women who are approached by kings .There are other sorts of dialogues , say, when Jabala is taught by bulls and birds (Ch. Up 4.4-9) , Upakosala by the sacred fires (Ch. Up. 4.10-15), and Baka is by a dog (Ch. Up 1.12).
Nothing in the Upanishads is more vital than the relationship between a student and his guide. The teacher talks, out his experience, about his ideas of the nature of the world, of truth etc. or about particular array of phenomena visualized through mental images that stay etched in memory.
An Upanishad-teacher ignites in the heart of the boy a spark that sets ablaze his desire to learn and to know the central principles which make sense of the world we live in. The guide inflames the sense of challenge, the urge to reach beyond the boy’s grasp and to know the unknown. The Brihadaranyaka Upanishad calls upon :
‘You are what your deep, driving desire is; as your desire is, so is your will (sa yathā-kāmo bhavati tat-kratur-bhavati); as your will is, so is your deed (yat-kratur-bhavati tat-karma kurute) ; as your deed is, so is your destiny (yat-karma kurute tad-abhi-saṃpadyate”- (Brhu. Up. 4.4.5).
sa yathākāmo bhavati tat-kratur bhavati | yat-kratur bhavati tat karma kurute | yat karma kurute tad abhi-saṃpadyate || BrhUp_4,4.5 |
In the end, all achievement is fueled by burning desire.
The Bhagavad-Gita suggests that an ardent seeker of truth should approach a learned teacher in humility and seek instructions from him; question him repeatedly:
Tad viddhi pranipatena pariprasnena sevaya I Upadeksyanti te jnanam jnaninas tattva-darsinah II (B G.; Ch.4; verse 34)
The student questions the teacher not because he doubts (samshaya) the wisdom or the understanding of the teacher; nor is he / she questioning the authenticity of the teaching . The questions are asked with open mind and guileless heart; and, are meant to clear doubts, and to gain a flawless understanding of the teaching.
The teacher is neither annoyed nor does he discourage the student from asking questions. On the other hand, he encourages the learner to examine, enquire and test the teaching handed down to him. A true teacher, in a Samvada does not prescribe or proscribe. He lets the student the freedom to think, to ponder over and to find out for himself the answers to his questions. A student needs humility, persistence, and honesty of purpose to go further and to arrive at his own understanding.
The Buddha, the best of the teachers, also adopted a similar approach. He insisted that his followers should not try borrowing ideas or experiences from him; but they should arrive at their own. In the first sermon he delivered (Dhammacakkappavattana Sutta) in the Deer-park (Miga-daya) at Isipatana (Saranath), soon after attaining enlightenment, he asked his listeners:
O monks and wise men, do not accept my Dharma merely out of respect for me, but analyze and test it the way a goldsmith examines a pieces of gold by burning , cutting and rubbing it on a touchstone.(please see the note below)
A teaching would not be true, valid or trustworthy merely because it was uttered by an eminent person of great renown. It would be so only in case it is thoroughly tested, clearly understood and truthfully brought into one’s own experience.
The Buddha guides the aspirant on the path that leads to right-understanding. But he disclaims any personal authority; and asks the follower to work it out himself. The follower when he succeeds in attaining the enlightenment will not become a second Buddha or a replica of the Buddha. In the final analysis, both the Buddha and his follower free themselves from the bonds of samsara; yet, each retains his individuality.
[ This often quoted analogy of testing a piece of gold appears in many texts ; such as : Jnanasara-samuccaya (31) a Sanskrit text of a later period (perhaps a translation of the Tibetan text – sTug-po bkod-pa’i mdo) ; in Nyāya-bindu-pūrvapakṣa-saṃkṣipti, a commentary on Dharmakīrti’s, Nyāyabindu (1.18–1.21) and also in Śāntarakṣita’s Tattva-saṁgraha (verse 3588) .
It reads in Sanskrit as :
Tāpāc chedāc ca nikasat svarnam iva panditaih / Parikshya blikshavo grāhyam madvaco na tu gauravāt
However, the kalama Sutta appearing in Aṅguttara Nikaya (III.653) , which is a part of Tipitaka, merely lays down the principle of taking an objective view after a thorough examination (charter of free inquiry ):
“Come, O Kālāmas, Do not accept anything thinking that thus have we heard it from a long time (anussava). Do not accept anything thinking that it has thus been handed down through many generations (paramparā). Do not accept anything on account of rumours (itikirā). Do not accept anything just because it accords with your scriptures (piṭaka-sampadāna). Do not accept anything by mere surmise (takka-hetu); nor upon an axiom (naya-hetu). Do not accept anything by mere inference (ākāra-parivitakka). Do not accept anything by merely upon a bias towards a notion that has been pondered over (diṭṭhi-nijjhān-akkh-antiyā). Do not accept anything by coming under another’s seems ability (bhabba-rūpatāya). Do not accept anything merely because the monk-teacher says so (samaṇo no garū). Do not accept anything thinking that the ascetic is respected by us (and therefore it is right to accept his word.)
“Kalamas, when you know for yourselves —these things are immoral, these things are blameworthy, these things are censured by the wise, these things when performed and undertaken, conduce to ruin and sorrow – then indeed you do reject them.
“But Kalamas, when you know for yourselves – these things are good; these things are blameless, these things are praised by the wise; these things when undertaken and observed, lead to well-being and happiness- enter upon and abide in them. ]
Continued in Part Two
..Vada, Jalpa and Vitanda
Sources and References:
A History of Indian Logic: Ancient, Mediaeval, and Modern Schools By Mahamahopadyaya Satis Chandra Vidyabhusana
The Character of Logic in IndiaEdited by Bimal Krishna Matilal, Jonardon Ganeri, Heeraman Tiwari
The Nyâya Sûtras of Gotama by Nandalal SinhaH
indu Philosophy by Theos Bernard
A History of Indian Philosophy, Volume 1 By Prof.Surendranath Dasgupta
The Birth of Meaning in Hindu Thought by David B. Zilberman
History of Indian philosophy: The philosophy of the Veda and of …, Volume 1By Erich Frauwallner
All images are taken from Internet