Anumana

''Pramana'' (Sanskrit: प्रमाण, ) literally means " proof" and "means of knowledge".pramANa
Sanskrit-English Dictionary, Koeln University, GermanyJames Lochtefeld, "Pramana" in The Illustrated Encyclopedia of Hinduism, Vol. 2: N-Z, Rosen Publishing. , pages 520-521 In Indian philosophies, pramana are the means which can lead to knowledge, and serve as one of the core concepts in Indian epistemology. It has been one of the key, much debated fields of study in Hinduism, Buddhism and Jainism since ancient times. It is a theory of knowledge, and encompasses one or more reliable and valid means by which human beings gain accurate, true knowledge. The focus of pramana is how correct knowledge can be acquired, how one knows, how one does not know, and to what extent knowledge pertinent about someone or something can be acquired.DPS Bhawuk (2011), Spirituality and Indian Psychology (Editor: Anthony Marsella), Springer, , page 172

While the number of pramanas varies widely from system to system, many ancient and medieval Indian texts identify six ''pramanas'' as correct means of accurate knowledge and to truths: Three central pramanas which are almost universally accepted, which are perception (Sanskrit ''pratyakṣa),'' inference (''anumāna''), and "word", meaning the testimony of past or present reliable experts (''Śabda''); and more contentious ones, which are comparison and analogy ('' upamāna''), postulation, derivation from circumstances (''arthāpatti''), and non-perception, negative/cognitive proof (''anupalabdhi'').Gavin Flood, An Introduction to Hinduism, Cambridge University Press, , page 225 Each of these are further categorized in terms of conditionality, completeness, confidence and possibility of error, by each school of Indian philosophies.

The various schools of Indian philosophies vary on how many of these six are epistemically reliable and valid means to knowledge. For example, the Carvaka school of the Śramaṇa tradition holds that only one (perception) is a reliable source of knowledge, Buddhism holds two (perception, inference) are valid means, Jainism holds three (perception, inference and testimony),John A. Grimes, A Concise Dictionary of Indian Philosophy: Sanskrit Terms Defined in English, State University of New York Press, , page 238 while Mimamsa and Advaita Vedanta schools of Hinduism hold all six are useful and can be reliable means to knowledge.
*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 The various schools of Indian philosophy have debated whether one of the six forms of ''pramana'' can be derived from other, and the relative uniqueness of each. For example, Buddhism considers Buddha and other "valid persons", "valid scriptures" and "valid minds" as indisputable, but that such testimony is a form of perception and inference ''pramanas''.

The science and study of ''pramanas'' is called ''Nyaya''.Karl Potter (2002), Presuppositions of India's Philosophies, Motilal Banarsidass, , pages 25-26

Etymology

''Pramāṇa'' literally means "proof" and is also a concept and field of Indian philosophy. The concept is derived from the Sanskrit roots, ''pra'' (प्र), a preposition meaning "outward" or "forth", and ''mā'' (मा) which means "measurement". ''Pramā'' means "correct notion, true knowledge, basis, foundation, understand", with pramāṇa being a further nominalization of the word. Thus, the concept ''Pramāṇa'' implies that which is a "means of acquiring ''prama'' or certain, correct, true knowledge".

''Pramāṇa'' forms one part of a trio of concepts, which describe the ancient Indian view on how knowledge is gained. The other two concepts are knower and knowable, each discussed in how they influence the knowledge, by their own characteristic and the process of knowing. The two are called ''Pramātŗ'' (प्रमातृ, the subject, the knower) and ''Prameya'' (प्रमेय, the object, the knowable).

The term ''Pramana'' is commonly found in various schools of Hinduism. In Buddhist literature, ''Pramana'' is referred to as ''Pramāṇavāda''. ''Pramana'' is also related to the Indian concept of ''Yukti'' (युक्ति) which means active application of epistemology or what one already knows, innovation, clever expedients or connections, methodological or reasoning trick, joining together, application of contrivance, means, method, novelty or device to more efficiently achieve a purpose.R Narasimha (2012), Asia, Europe, and the Emergence of Modern Science: Knowledge Crossing Boundaries, Palgrave Macmillan, , pages 95-97 ''Yukti'' and ''Pramana'' are discussed together in some Indian texts, with ''Yukti'' described as active process of gaining knowledge in contrast to passive process of gaining knowledge through observation/perception. The texts on ''Pramana'', particularly by Samkhya, Yoga, Mimamsa and Advaita Vedanta schools of Hinduism, include in their meaning and scope "Theories of Errors", that is why human beings make error and reach incorrect knowledge, how can one know if one is wrong, and if so, how can one discover whether one's epistemic method was flawed, or one's conclusion (truth) was flawed, in order to revise oneself and reach correct knowledge.

Hinduism

Six ''pramanas''

Hinduism identifies six ''pramanas'' as correct means of accurate knowledge and to truths: ''Pratyakṣa'' (perception), ''Anumāṇa'' (inference), ''Upamāṇa'' (comparison and analogy), ''Arthāpatti'' (postulation, derivation from circumstances), ''Anupalabdhi'' (non-perception, negative/cognitive proof) and ''Śabda'' (word, testimony of past or present reliable experts).

In verse 1.2.1 of the Taittirīya Āraṇyaka (c. 9th–6th centuries BCE), "four means of attaining correct knowledge" are listed: ''smṛti'' ("scripture, tradition"), ''pratyakṣa'' ("perception"), ''aitihya'' ("expert testimony, historical tradition"), and ''anumāna'' ("inference").

In some texts such as by Vedvyasa, ten ''pramanas'' are discussed, Krtakoti discusses eight epistemically reliable means to correct knowledge. The most widely discussed ''pramanas'' are:

''Pratyakṣa''

''Pratyakṣa'' (प्रत्यक्ष) means perception. It is of two types in Hindu texts: external and internal. External perception is described as that arising from the interaction of five senses and worldly objects, while internal perception is described by this school as that of inner sense, the mind.MM Kamal (1998), The Epistemology of the Carvaka Philosophy, Journal of Indian and Buddhist Studies, 46(2): 13-16 According to Matt Stefan, the distinction is between direct perception (''anubhava'') and remembered perception (''smriti'').

The ancient and medieval Indian texts identify four requirements for correct perception: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
# ''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, 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);
# ''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).

Some ancient scholars proposed "unusual perception" as ''pramana'' and called it internal perception, a proposal contested by other Indian scholars. The internal perception concepts included ''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). Further, some schools of Hinduism considered and refined rules of accepting uncertain knowledge from ''Pratyakṣa-pranama'', so as to contrast ''nirnaya'' (definite judgment, conclusion) from ''anadhyavasaya'' (indefinite judgment).

''Anumāna''

''Anumāna'' (अनुमान) means ‘inference’ in Sanskrit, though it often is used to mean ‘guess’ in modern Indian languages like Hindi. In the context of classical philosophy, it is described as reaching a new conclusion and truth from one or more observations and previous truths by applying reason. Observing smoke and inferring fire is an example of ''Anumana''. In all except one Hindu philosophies, this is a valid and useful means to knowledge. The method of inference is explained by Indian texts as consisting of three parts: ''pratijna'' (hypothesis), ''hetu'' (a reason), and ''drshtanta'' (examples).James Lochtefeld, "Anumana" in The Illustrated Encyclopedia of Hinduism, Vol. 1: A-M, Rosen Publishing. , page 46-47 The hypothesis must further be broken down into two parts, state the ancient Indian scholars: ''sadhya'' (that idea which needs to proven or disproven) and ''paksha'' (the object on which the ''sadhya'' is predicated). The inference is conditionally true if ''sapaksha'' (positive examples as evidence) are present, and if ''vipaksha'' (negative examples as counter-evidence) are absent. For rigor, the Indian philosophies also state further epistemic steps. For example, they demand ''Vyapti'' - the requirement that the ''hetu'' (reason) must necessarily and separately account for the inference in "all" cases, in both ''sapaksha'' and ''vipaksha''. A conditionally proven hypothesis is called a ''nigamana'' (conclusion).

''Upamāna''

''Upamāna'' (उपमान) means comparison and analogy. Some Hindu schools consider it as a proper means of knowledge. ''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 ''upamanam'', while the attribute(s) are identified as ''samanya''.Monier Williams (1893), Indian Wisdom - Religious, Philosophical and Ethical Doctrines of the Hindus, Luzac & Co, London, pages 457-458 Thus, explains Monier Williams, if a boy says "her face is like the moon in charmingness", "her face" is ''upameyam'', the moon is ''upamanam'', and charmingness is ''samanya''. The 7th century text Bhaṭṭikāvya 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 ''Upanama'' and their value in epistemology are debated.

''Arthāpatti''

''Arthāpatti'' (अर्थापत्ति) means postulation, derivation from circumstances. In contemporary logic, this ''pramana'' is similar to circumstantial implication. As example, if a person left in a boat on river earlier, and the time is now past the expected time of arrival, then the circumstances support the truth postulate that the person has arrived. Many Indian scholars considered this ''pramana'' as invalid or at best weak, because the boat may have gotten delayed or diverted. However, in cases such as deriving the time of a future sunrise or sunset, this method was asserted by the proponents to be reliable. Another common example for ''arthapatti'' in ancient Hindu texts is, that if "Devadatta is fat" and "Devadatta does not eat in day", then the following must be true: "Devadatta eats in the night". This form of postulation and deriving from circumstances is, claim the Indian scholars, a means to discovery, proper insight and knowledge. The Hindu schools that accept this means of knowledge state that this method is a valid means to conditional knowledge and truths about a subject and object in original premises or different premises. The schools that do not accept this method, state that postulation, extrapolation and circumstantial implication is either derivable from other ''pramanas'' or flawed means to correct knowledge, instead one must rely on direct perception or proper inference.

''Anupalabdi''

''Anupalabdi'' (अनुपलब्धि) means non-perception, negative/cognitive proof. ''Anupalabdhi pramana'' suggests that knowing a negative, such as "there is no jug in this room" is a form of valid knowledge. If something can be observed or inferred or proven as non-existent or impossible, then one knows more than what one did without such means. In the two schools of Hinduism that consider ''Anupalabdhi'' as epistemically valuable, a valid conclusion is either ''sadrupa'' (positive) or ''asadrupa'' (negative) relation — both correct and valuable. Like other ''pramana'', Indian scholars refined ''Anupalabdi'' to four types: non-perception of the cause, non-perception of the effect, non-perception of object, and non-perception of contradiction. Only two schools of Hinduism accepted and developed the concept "non-perception" as a ''pramana''. The schools that endorsed ''Anupalabdi'' affirmed that it as valid and useful when the other five ''pramanas'' fail in one's pursuit of knowledge and truth.

''Abhava'' (अभाव) means non-existence. Some scholars consider ''Anupalabdi'' to be same as ''Abhava'', while others consider ''Anupalabdi'' and ''Abhava'' as different. ''Abhava-pramana'' has been discussed in ancient Hindu texts in the context of ''Padārtha