Buddhist logic, the categorical nomenclature modern Western discourse has extended to Buddhadharma traditions of 'Hetuvidya' (Sanskrit) and 'Pramanavada' (Sanskrit), which arose circa 500CE, is a particular development, application and lineage of continuity of 'Indian Logic', from which it seceded. Indian logic, and Buddhist Logic—in main heralded by Dignāga (c. 480 - 540 CE)—are both primarily studies of 'inference'-patterns, where ‘inference’ is a gloss of anumāna (Sanskrit).
Sadhukhan, et al. (1994: p. 7) frames the centrality of 'syllogism' to Buddhist Logic and foregrounds its indivisibility as an investigative, authenticating and proofing tool instituted to establish the valid cognitive insights of the Buddhadharma:
Buddhist logic obviously contains the forms and nature of syllogism, the essence of judgement, etc. for which it deserves the name of logic. But that logic is not only logic it also establishes the doctrines of the Buddhists. Thus the philosophical tenets were the fulcrum and the logic developed as tools to establish those.
Following the work of Tucci (1929) and the critique of Anacker (2005, rev.ed.) upon the collation of Frauwallner (1957), it is now understood that Vasubandhu's Vāda-vidhi ("A Method for Argumentation") refined the five argument logic of the Nyāya-sūtra to a three argument form and not his pupil Dignāga. In addition to pruning the two redundant arguments from the syllogism, Vasubandhu tendered a further qualification: he posited that a sound relationship, a 'logical pervasion' (vyapti) needs to be defined between the first and second arguments, a relationship between the 'Demonstrandum' (pratijna) and the 'Justification' (hetu) that is assumed in the Nyāya-sūtra and other literature of the Nyāya school. This logical pervasion is required to fashion sound arguments. Vasubandhu's Vāda-vidhi was reconstructed by Frauwallner from embedded quotations harvested from the works of Dignāga, amongst others. Dignāga as the oft-cited wellspring of the logical triune in the Buddhadharma is now invalidated.
Buddhist Logic as Distinct from Classical Logic
‘Indian Logic’ should be understood as being a different system of logic than modern classical logic (e.g. modern predicate calculus), but as anumāna-theory, a system in its own right. ‘Indian Logic’ was influenced by the study of grammar, whereas Classical Logic which principally informed modern Western Logic was influenced by the study of mathematics.
Nomenclature, orthography and etymology
'Buddhist logic' (English)
Vidyabhusana (1921), Randle (1930) and Stcherbatsky (1930) employed terms such as “Indian Logic” and “Buddhist Logic” which established this terminology, though a key difference between Western Logic and Indian Logic is that certain epistemological issues are included within Indian Logic, whereas in modern Western Logic they are deliberately excluded. Indian Logic includes general questions regarding the ‘nature of the derivation of knowledge’, epistemology, from information supplied by evidence, evidence which in turn may be another item of knowledge.
Etymology: anu ("subsequent") + manas ("perception, mind") is identified as a ‘source of knowledge’, a pramāṇa. Though not the founders of 'Indian logic', the Nyaya school first codified and established a 'system of logic'. The Nyāya recognized four 'sources of knowledge' (pramana): perception, inference, comparison and testimony.
Antecedents and secession
'Nyāya' (Skt. "recursion", with the semantic amplification of 'syllogism, inference') is the name given to one of the six 'orthodox' (astika) schools of Sanatana Dharma, which may be understood as "the school of logic." The Nyaya is founded in the Nyaya Sutras, attributed to Gotama (2nd century CE). Buddhist logic inherited much of the architecture of Nyaya's methodology, but where the Nyaya recognised a set of four pramanas—perception, inference, comparison and testimony—the logic of Buddhadharma only recognized two: perception and inference.
A syllogism is a form of inference. Ames (1993: p. 210), holds that Bhāvaviveka (c. 500 - c. 578) appears to be the first Buddhist logician to employ the 'formal syllogism' (Wylie: sbyor ba'i tshig; Sanskrit: prayoga-vākya) of Indian Logic in expounding the Mādhyamaka, which he employed to considerable effect in his commentary to Nagarjuna's Mūlamadhyamakakārikā entitled the Prajñāpradīpa. Though due to the work of Anacker (2005, rev.ed.) and those upon whom his work is founded, we know that the first Buddhist to refine the syllogism to its three-line form is Vasubhandu.
Dharmic logic in Western discourse & literature review
Vidyabhusana (1921), Randle (1930) and Stcherbatsky (1930)
Dr S.C. Vidyabhusana, Mahapandit Rahul Sankrityayan, Dr M. K. Ganguli, A. Vostrikov, Prof. Giuseppe Tucci, B. Baradiin, V. Vassiliev (1818—1900), E. E. Obermiller (1901–1935), Prof. Gerhard Oberhammer, Prof. E. Frauwallner, F. Th. Stcherbatsky, E. Steinkellner.
Robinson (1957: p. 295) holds that, building upon the methodology of Schayer , Nakamura (1954)
...presents the case for the superiority of modern scientific, notational logic as an instrument for investigating Indian logic. Notational statement avoids the pitfalls and awkwardness of linguistic statement and rhetorical logic. It does not necessitate conversion of Indian forms into the standard forms of traditional Western logic, but clarifies the traditional Indian structure without requiring reformulation. To Nakamura's points I may add that modern logic asks a greater range of questions and hence sharpens the observation of the investigator.
Pramana sets as determining traditions of Dharma
Decisive in distinguishing Buddhadharma from what is generally understood as Sanatana Dharma is the issue of epistemological justification. All schools of Indian logic recognize various sets of 'valid justifications for knowledge' or pramana. The Buddhadharma recognizes a pramana set that is smaller than the other Dharmic Traditions. Most pramanavada of Dharmic Traditions accept 'perception' (Sanskrit: pratyakṣa) and 'inference' (Sanskrit: anumāna), for example, but for some schools of Sanatana Dharma and Buddhadharma the 'received textual tradition' (Sanskrit: āgamāḥ) is an epistemological category equal to perception and inference (although this is not necessarily true for some other schools). The Buddhadharma accepts 'received textual tradition' or āgamāḥ, including Buddhavacana, only if it accords with pratyakṣa and anumāna. Historically, Shakyamuni Buddha was qualifying the unquestionable authority of the Vedas on grounds of ahimsa as according to the Vedic Tradition of Sanatana Dharma, the Vedas are apauruṣeya "not of human agency," are supposed to have been directly revealed, and thus are called śruti ("what is heard"). Vedic injunctions required sacrifices, Śrauta (an etymon of the English 'slaughter'), particularly 'animal sacrifices' (Pashu-Yajna, Ashvamedha) and which the compassionate Shakyamuni Buddha countered.
Thus, in the Sanatana Dharma traditions, if a claim was made that could not be substantiated by appeal to the textual canon, it would be considered as ridiculous as a claim that the sky was green and, conversely, a claim which could not be substantiated via conventional means might still be justified through textual reference, differentiating this from the epistemology of hard science. Some schools of Buddhadharma, on the other hand, rejected an inflexible reverence of accepted doctrine. As the Buddhavacana Kalama Sutta III.65 states:
Do not accept anything by mere tradition ... Do not accept anything just because it accords with your scriptures ... Do not accept anything merely because it agrees with your pre-conceived notions ... But when you know for yourselves – these things are moral, these things are blameless, these things are praised by the wise, these things, when performed and undertaken, conduce to well-being and happiness – then do you live acting accordingly.
This verse is however taken out of context. In the Kalama Sutta the Buddha was talking to non-Buddhists and those were not already Buddhist disciples. Dhammapala's commentary on the Nettipakarana says "for there is no other criterion beyond a text."
Early Buddhism and the rise of Nagarjuna
Early Buddhist philosophers and exegetes of one particular early school (as opposed to Mahayana), the Sarvastivadins, created a pluralist metaphysical and phenomenological system, in which all experiences of people, things and events can be broken down into smaller and smaller perceptual or perceptual-ontological units called dharmas. Other schools incorporated some parts of this theory and criticized others. The Sautrantikas, another early school, and the Theravadins, the only surviving early Buddhist school, criticized the realist standpoint of the Sarvastivadins.
The Mahayanist Nagarjuna, one of the most influential Buddhist thinkers, promoted classical Buddhist emphasis on phenomena and attacked Sarvastivada realism and Sautrantika nominalism in his magnum opus The Fundamental Verses on the Middle Way.
Robinson (1957: p. 293) makes an opinion that builds upon the foundation of Stcherbatsky (1927):
The Madhyamaka denies the validity of logic, i.e., of discursive conceptual thought, to establish ultimate truth. On the charge that in doing so he himself resorts to some logic, he replies that the logic of common life is sufficient for showing that all systems contradict one another and that our fundamental conceptions do not resist scrutiny.
Catuskoti (Sanskrit), had antecedents in the Vedas and is also evident in a mutually iterating form known by the Greek term 'Tetralemma', where 'tetra' holds the semantic field of "four" and 'lemma' holds the semantic field "auxiliary proposition".
Indian Transmission lineages to Tibet and concomitant translations
Tom Tillemans (1998: p. 1), in discussing the Tibetan translation and assimilation of the Buddhadharma logico-epistemological traditions embodied by the legacy of Dignāga (c. 480 - 540 CE) and Dharmakīrti (c. 7th century), identifies two currents and transmission streams:
- first current, principally geographical located at Sangpu Neutok and grounded in the works of Ngok Lodzawa Loden Shayrap (1059–1109) and Chapa Chögyi Sengge (1109–69) and their disciples. Chapa’s Tshad ma’i bsdus pa (English: 'Summaries of Epistemology and Logic') became the groundwork for the ‘Collected Topics’ (Tibetan: Düra; Wylie: bsdus grwa) literature, which in large part furnished Gelugpa-based logical architecture and epistemology.
- second current of Sakya Pandita (1182–1251) who wrote the Tshad-ma rigs-gter (English: "Treasury of Logic on Valid Cognition"), who vehemently redressed the logical architecture of the Gangpu Neutok positions.
Sangpu Neutok (Wylie: gSang-phu Ne'u-thog)
Dudjom (1904–87) and others (1991: p. 577) hold that at the time of Longchenpa (1308–1364/1369) who studied there, Sangpu Neutok (Wylie: gSang-phu Ne'u-thog)—a seminary founded in 1073 by the translator (Tib. lotsawa) Ngok Lekpei Sherap (1059–1109)—was "the great academy for the study of logic in Tibet."
The Vajrayana tradition of the Tibetan Buddhist Gelugpa—with their penchant for dialectic and courtyard debate—instituted, developed and perpetuated the systems of Indian Logic and Buddhist Logic that they had inherited, significantly contributing to and extending the traditions of Hetuvidya and Pramanavada within the logico-epistemological traditions of the Buddhadharma. Particularly, post-Candrakirti (600 – c. 650), the Gelugpa refined the Catuskoti and Shunyata into the Prasangika.
Vasubandhu (fl. 4th century)
Doctrine of Trairūpya
Dharmakirti's Theory of Inference
Dharmakirti (c. 7th century) was an Indian scholar (pandita) and Buddhist who contributed significantly to the Buddhist development and application of Indian philosophical logic. He was one of the primary theorists of Buddhist atomism, according to which the only items considered to exist are momentary atoms (in the Buddhist sense) and states of consciousness. The following exposition of Dharmakirti's theory of inference was drawn from Prasad (2002).
Doctrine of Anyapoha
Apoha is negative abhavatmaka in nature. Apohas are different due to the diversity in apohyas (things to be excluded). The word apoha, which is the abridged form of anyapoha, means the 'exclusion of negation of others (ataddvyavrtti)'. For example, the word 'cow' gives its own meaning only by the exclusion of all those things which are other than cow. Dingnaga declares that a word can express its own meaning only by repudiating opposite meanings, just as words like 'krtaka' (i.e. that which has origin) designate their meanings only through the exclusion of their opposite like 'akraka' (i.e. that which does not have origin).
Dingnaga admits that apoha can also possess some characteristics of the realists' universals such as oneness, enternity, complete subsistence in each individual, etc. He apprehends the concept of universal through the negation of its non-self. He explains that if the non-self of a universal is absent in a locus, then its presence in that locus can be inferred. For example, a cow is qualified by the deniability of the non-cow. This concept of Dingnaga's is similar to that Hegel who also believes that the universality of a concept is posited through its negativity.
Apoha is not the object of sense perception (pratyaksa). It is apprehensible only through word or inference. In essence, Dingnaga uses anyyapoha as a substitute for universal. The concept of apoha depends upon the law of contradiction. The words blue and non-blue negate each other, simply because they are opposite to each other. According to Dingnaga, a similar exclusion of others is due to the non-apprehension of the meaning of a particular word in other words. A particular word excludes the other particular words because its own meaning is not apprehended in the other ones. For example, the word simsapa-tree excludes the word palasa-tree because its own meaning is not available in the latter one.
- Argument: vada, rtsod pa
- Characteristic: laksana, mtshan nid
- Condition: pratyaya, rkyen
- Demonstrandum: sadhya, bsgrub par bya ba
- Demonstrator: sadhaka, grub byed
- Dialectician: tartika, rtog ge ba
- Dialectics: tarka, rtog ge
- Direct perception: pratyaksa, mnon sum
- Event: dharma, chos
- Event-associate: dharmin, chos can
- Exemplification: drstanta, dpe
- Inference: anumana, rjes su dpag pa
- Interference: vyavakirana, hdres pa
- Invariable concomitance: avinabhava, med na mi hbyun ba
- Judgment: prajnanana, shes-rab
- Justification: hetu, gtan-tshigs
- Means of cognition: pramana, tshad pa
- Means of evidence: linga, rtags
- Pervading/pervasion/logical pervasion: vyapti, khyab pa
- Tobden, Tashi (Ed.in Chief); Sadhukhan, Sanjit Kumar (compiler); Dokham, Rigzin Ngodub (compiler) (1994). Bulletin of Tibetology: Special Volume on the History of Buddhist Logic. New Series, no.3. Gangtok, Sikkim: Sikkim Research Institute of Tibetology. Source: (accessed: Saturday March 14, 2009), p.5
- Pramanasamuccaya of Dingnaga : 5/14,1
- Tucci, Giuseppe (1929). "Buddhist Logic before Dinnaga (Asanga, Vasubandhu, Tarka-sastras)". Journal of the Royal Asiatic Society of Great Britain and Ireland: pp.451-488.
- Tobden, Tashi (Ed.in Chief); Sadhukhan, Sanjit Kumar (compiler); Dokham, Rigzin Ngodub (compiler) (1994). Bulletin of Tibetology: Special Volume on the History of Buddhist Logic. New Series, no.3. Gangtok, Sikkim: Sikkim Research Institute of Tibetology. Source: (accessed: Monday March 16, 2009), p.7.
- 'Six Buddhist Nyaya Tracts', p. 3, line7 edited by M.M. Har Prasad Shastri, Bibliotheca Indica, Calcutta,1910
- Frauwallner, Erich (1957). 'Vasubandhu's Vādavidhiḥ'. Wiener Zeitschrift für die Kunde Süd-und Ost-Asiens 1, 1957, 104ff.
- Anacker, Stefan (2005, rev.ed.). Seven Works of Vasubandhu: The Buddhist Psychological Doctor. Delhi, India: Motilal Banarsidass. (First published: 1984; Reprinted: 1986, 1994, 1998; Corrected: 2002; Revised: 2005), p.31
- Mohanty, Jitendra Nath (1992). Reason and Tradition in Indian Thought: An Essay on the Nature of Indian Philosophical Thinking. New York, USA: Oxford University Press. ISBN 0-19-823960-2, p.106
- Matilal, Bimal Krishna (author), Ganeri, Jonardon (editor) & (Tiwari, Heeraman)(1998). The Character of Logic in India. Albany, NY, USA: State University of New York Press. ISBN 0-7914-3739-6 (HC:acid free), p.14
- Ames, William L. (1993). "Bhāvaviveka's Prajñāpradīpa ~ A Translation of Chapter One: 'Examinations of Causal Conditions' (Pratyaya)". Journal of Indian Philosophy, 1993, vol.21. Netherlands: Kluwer Academic Publishers, p.210
- Schayer, Stanislaw (1933). "Altindische Antizipationen der Aussagenlogik." Bulletin international de l'Academie Polonaise des Sciences et philologie, 1933, pp. 99-96.
- Nakamura, Hajime (1954). "Kukao no kigo-ronrigaku-teki ketsumei, (English: 'Some Clarifications of the Concept of Voidness from the Standpoint of Symbolic Logic')" Indogaku-bukkyogaku Kenkyu, No. 5, Sept., 1954, pp. 219-231.
- Robinson, Richard H. (1957). 'Some Logical Aspects of Nagarjuna's System'. Philosophy East & West. Volume 6, no. 4 (October 1957). University of Hawaii Press. Source: (accessed: Saturday March 21, 2009), p.295
- Apohasiddhi, (p. 3) RatnakÏrti, Bib. Indica. See also Buddhist Doctrine of Universal Flux (p. 132-133) by Satkari Mukerjee.
- Apte, pp. 109f. has "not of the authorship of man, of divine origin"
- Apte 1965, p. 887
- Muller 1891, pp. 17–18
- Historically, Pashu-yajna or "animal sacrifices" were initially according to Vedic injunction not a sacrifice of animals but a sacrifice for animals, that did not entail an offering of meat. With the passage of time and due to the nature of the Varnashrama Dharma, this changed. In Varnasrama Dharma, all varnas other than Brahmanas were meted meat due to the nature of their work and employment: proscribed and prescribed at different times and according to changing conventions. Due to sacred prescription of the Veda and the Triguna of the Ayurveda, Brahmanas were required to refine a more sattvic palate due to their sattvic duties. The other varnas may be required to eat meat according to their Dosha and other factors. The Tantric Buddhist tradition though, in continuation of ancient rites from Persia, Medieval Bengal of the Mahasiddha, Zhangzhung and elsewhere, have upheld the Ganacakra (refer E. S. Drower & ).
- "...Hegel was quite right when he said that Negativity is the soul of the world. Buddhist logic: part -I (1930) page no.498 : F. Th. Stcherbatsky.
- Kalama Sutta, Anguttara Nikaya III.65
- Nettipakarana, Pali Text Society (1902), page XI; translation by Nanamoli, The Guide (1962), Pali Text Society, page xi. The original reads: na hi pāḷito aññaṃ pamāṇataraṃ atthi, in which the Pali term pamāṇa is equivalent to Sanskrit pramāṇa.
- Randall Collins, The Sociology of Philosophies: A Global Theory of Intellectual Change. Harvard University Press, 2000, pages 221-222.
- Robinson, Richard H. (1957). 'Some Logical Aspects of Nagarjuna's System'. Philosophy East & West. Volume 6, no. 4 (October 1957). University of Hawaii Press. Source: (accessed: Saturday March 21, 2009), p.293
- Tillemans, Tom J.F. (1998). 'Tibetan philosophy'. In E. Craig (Ed.), Routledge Encyclopedia of Philosophy. London: Routledge. Source: (accessed: Saturday March 14, 2009), p.1
- Pettit (?: p.469): "A treatise on Buddhist logic (pramana) by Sakya Pandita, which is probably the most important of its kind in Tibet except for the major works of Dignaga and Dharmakirti. Mipham is the author of a commentary on this text entitled Tshad ma rig pa'i gter mchan gyis 'grel pa, written at the Sakya monastery of rDzong gsar bkra shis lha rte)"
- arthasya bahudharmasca sarve lingannakalpitam. yo'nubandho'nyasmat vyatireka'dhigamyate.: 'Pramanasamuccaya' : 2:13
- Dorje, Jikdrel Yeshe (Dudjom Rinpoche, author), & translated and edited: Gyurme Dorje and Matthew Kapstein (1991). The Nyingma School of Tibetan Buddhism: Its Fundamentals and History. Boston, USA: Wisdom Publications. ISBN 0-86171-199-8, p.577.
- bhedo bhedantarartham tu virodhitvad apohate, samanyantara bhedartha svasamanya virodhinah . : 'Pramanasamuccaya' 5:28 The is based on a Research paper read at Icanasa-2000
- Prasad, Rajendra (2002). Dharmakirti's Theory of Inference : Revaluation and Reconstruction. New Delhi, India: Oxford University Press.
- Jayatilleke, K.N. (1967). 'The Logic of Four Alternatives'. Philosophy East and West. Vol.17:1-4. Hawaii, USA: University of Hawaii Press.
- Rogers, Katherine Manchester. Tibetan Logic Snow Lion Publications, 2009.
- Van Der Kuijp, Leonard W. J. (1978). 'Phya-pa Chos-kyi seng-ge's impact on Tibetan epistemological theory'. Journal of Indian Philosophy. Volume 5, Number 4, August, 1978. Springer Netherlands. ISSN 0022-1791 (Print) ISSN 1573-0395 (Online)
- Van Der Kuijp, Leonard W. J. (1987). 'An early Tibetan view of the soteriology of Buddhist epistemology: The case of 'Bri-gung 'jig-rten mgon-po'. Journal of Indian Philosophy. Volume 15, Number 1, March, 1987. ISSN 0022-1791 (Print) ISSN 1573-0395 (Online)
- Matilal, Bimal Krishna & Evans, Robert D. (eds.) (1986). Buddhist Logic and Epistemology. Studies in the Buddhist Analysis of Inference and Language, Dordrecht: Reidel.
- Wayman, Alex (1999). A Millennium of Buddhist Logic, Delhi: Matilal Barnassidas.
- Vidhabhusana, Satis Chandra (1907). History of the Mediaeval School of Indian Logic. Calcutta University.
- Tobden, Tashi (Ed.in Chief); Sadhukhan, Sanjit Kumar (compiler); Dokham, Rigzin Ngodub (compiler) (1994). Bulletin of Tibetology: Special Volume on the History of Buddhist Logic. New Series, no.3. Gangtok, Sikkim: Sikkim Research Institute of Tibetology.