Whether or not he considered all of them valid aside, it surely seems that he used all of them to arrive at conclusions. So unless there is a sutta that specifically says "I only use these pramanas, they are the only ones valid in my Dhamma." I don't see how it is entirely possible to say that the other four are never valid. It seems he greatly favored pratyaksa and anumana but didn't utterly refrain from and deny using the others.
It would be really amazing and impressive and Incredibly cohesive and consistent if the Buddha never used the four other paramanas in the 80,000 pages of the Pali Canon, talking to thousands of different people on thousands of different topics. I find that highly unlikely. So even if there is a scripture where the Buddha flatly says that the other four are not valid it seems improbable that in the thousands of other scriptures they are never used.
Thoughts?
Further reading on the pramanas below.
Buddhism accepts only two pramana (tshad ma) as valid means to knowledge: Pratyaksha (mngon sum tshad ma, perception) and Anumāṇa (rjes dpag tshad ma, inference).[12] Rinbochay adds that Buddhism also considers scriptures as third valid pramana, such as from Buddha and other "valid minds" and "valid persons". This third source of valid knowledge is a form of perception and inference in Buddhist thought. Valid scriptures, valid minds and valid persons are considered in Buddhism as Avisamvadin (mi slu ba, incontrovertible, indisputable).[12][57] Means of cognition and knowledge, other than perception and inference, are considered invalid in Buddhism.[9][10]
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Pratyakṣa Edit
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.[8][30] The ancient and medieval Indian texts identify four requirements for correct perception:[31] 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) 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).[31] 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).[32] 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).[33]
Anumāna Edit
Anumāna (अनुमान) means inference. It is described as reaching a new conclusion and truth from one or more observations and previous truths by applying reason.[34] Observing smoke and inferring fire is an example of Anumana.[8] In all except one Hindu philosophies,[35] 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).[36] 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.[36][37] A conditionally proven hypothesis is called a nigamana (conclusion).[38]
Upamāna Edit
Upamāna (उपमान) means comparison and analogy.[4][5] Some Hindu schools consider it as a proper means of knowledge.[39] Upamana, states Lochtefeld,[40] 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.[40] The subject of comparison is formally called upameyam, the object of comparison is called upamanam, while the attribute(s) are identified as samanya.[41] 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.[41] In various ancient and medieval texts of Hinduism, 32 types of Upanama and their value in epistemology are debated.
Arthāpatti Edit
Arthāpatti (अर्थापत्ति) means postulation, derivation from circumstances.[4][5] In contemporary logic, this pramana is similar to circumstantial implication.[42] 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.[43] 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.[44] 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.[45]
Anupalabdi Edit
Anupalabdi (अनुपलब्धि) means non-perception, negative/cognitive proof.[11] 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.[46] 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.[9] Abhava (अभाव) means non-existence. Some scholars consider Anupalabdi to be same as Abhava,[4] while others consider Anupalabdi and Abhava as different.[9][47] Abhava-pramana has been discussed in ancient Hindu texts in the context of Padārtha (पदार्थ, referent of a term). A Padartha is defined as that which is simultaneously Astitva (existent), Jneyatva (knowable) and Abhidheyatva (nameable).[48] Specific examples of padartha, states Bartley, include dravya (substance), guna (quality), karma (activity/motion), samanya/jati (universal/class property), samavaya (inherence) and vishesha (individuality). Abhava is then explained as "referents of negative expression" in contrast to "referents of positive expression" in Padartha.[48] An absence, state the ancient scholars, is also "existent, knowable and nameable", giving the example of negative numbers, silence as a form of testimony, asatkaryavada theory of causation, and analysis of deficit as real and valuable. Abhava was further refined in four types, by the schools of Hinduism that accepted it as a useful method of epistemology: dhvamsa (termination of what existed), atyanta-abhava (impossibility, absolute non-existence, contradiction), anyonya-abhava (mutual negation, reciprocal absence) and pragavasa (prior, antecedent non-existence).[48][49
Śabda Edit
See also: Śāstra pramāṇam in Hinduism and Sources of dharma
Śabda (शब्द) means relying on word, testimony of past or present reliable experts,[4][11] specifically the shruti, Vedas.[50] Hiriyanna explains Sabda-pramana as a concept which means reliable expert testimony. 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.[51] 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).[51] The reliability of the source is important, and legitimate knowledge can only come from the Sabda of reliable sources.[11][51] The disagreement between the schools of Hinduism has been on how to establish reliability. Some schools, such as Carvaka, state that this is never possible, and therefore Sabda is not a proper pramana. Other schools debate means to establish reliability.[52
-wiki on pramana