Part 1 - Distinction between a valid and an invalid reason

In Indian logic the fallacies of inference are all material fallacies. So far as the logical forms of inference are concerned, there can be no fallacy, since they are the same for all valid inferences. An inference, therefore, becomes fallacious by reason of its material conditions. The Nyaya account of the fallacies of inference is accordingly limited to those of its members or constituent propositions, and these have been finally reduced to those of the helu or the reason.' For the purpose of proof an inference is made to consist of five members, namely, pratijna, hetu, udaharana, upanaya and nigamana. As such, the validity of an inference depends on the validity of the pratijna and other constituent parts of it. If there is anything wrong with any of its members, the syllogism as a whole becomes fallacious. Hence there will be as many fallacies of inference as there are fallacies of its component parts, from the first proposition down to the conclusion. So we may speak of fallacies of the pratijna, etc., as coming under the fallacy of inference (nyayabhasa). But it must be admitted that the validity of an inference depends 2 1 Cf. The Aristotelian classification of fallacies into those in dictione and those extra dictionem. This agrees with the Nyaya classification in excluding the formal fallacies of undistributed middle, illicit process, and so on, from the list of fallacies. 2 The word nyayabhasa has been used by Vatsyayana in a technical sense to mean all such inferences as are opposed to preception and scriptural testimony. (Vide Nyaya-Bhasya, 1. 1. 1.). Here, however, it is used in its literal sense to mean the fallacies of inference. 36-(0.P. 103)

ultimately on the validity of the helu or the reason employed in it. So also the members of a syllogism turn out to be right or wrong according as they elaborate a right or wrong reason. The fallacies of inference ultimately arise out of the fallacious reason. So the Naiyayikas bring the fallacies of inference under the fallacies of the reason (hetvabhasa) and consider a separate treatment of the inferential fallacies due to the propositum, example, etc. (pratijnabhasa, drstantabhasa) as unnecessary and superfluous.' Now the question is: What is a fallacious middle (helu)? How are we to distinguish between a valid and an invalid middle? Literally speaking, hetvabhasa or the fallacious middle is one that appears as, but really is not, a valid reason or middle term of an inference. It appears as a valid ground of inference because it satisfies some of the conditions of a valid middle term. But on closer view it is found to be fallacious because it does not fulfil all the conditions of a valid ground of inference. As we have seen before, there are five conditions of the hetu or the middle term of an inference. First, the middle term must be a characteristic of the minor term (paksadharmala). Secondly, it must be distributively related to the major term, i.e. the major must be present in all the instances in which the middle is present (sapaksasattva). Thirdly, and as a corollary of the second condition, the middle term must be absent in all cases in which the major is absent (vipaksasattva). Fourthly, the iniddle term must not relate to obviously contradictory and absurd objects like the coolness of fire, etc. (abadhitavisayatva). Fifthly, it must not itself be validly contradicted by some other ground or middle term (asatpratipaksatva). Of these five conditions, the third docs not apply to the middle term of a kevalanvayi inference, because it is such that no case of its absence or non-existence can be found. Hence, with regard to it we cannot say that 1 Vide Tarkikaraksa, p. 236; Nyayamanjari, p. 572. 2 Vide Nyaya-varttika, 1. 2. 4.

the middle term must be absent in all cases in which the major is absent. Contrariwise, the second condition does not apply to the middle term of a kevalavyatireki inference since here the middle term is always negatively related to the major term. There is a universal relation between the absence of the middle and that of the major term. Of such a middle term we cannot say that wherever it is present the major must be present. It is only in the case of anvayavyatireki inferences that the middle term must satisfy all the five conditions. Hence it has been said that a valid iniddle term is one that satisfies the five or at least the four conditions as explained above.' As contrasted with this an invalid middle term (hetvabhasa) is that which violates one or other of the conditions of a valid ground of inference (hetu). It may be employed as the hetu or the middle term of an inference, but it fails to prove the conclusion it is intended to prove. There are different forms of the fallacious middle according to the different circumstances under which it may arise. All fallacious middle terms have been classified under the heads of the savyabhicara, viruddha, prakaranasama or satpratipaksa, sadhyasama or asiddha. kalatita and badhita. Kesava Misra observes that the fallacies of definition such as alivyapti or 'the too wide,' avyapti or ' the too narrow' and asambhava or and asambhava or 'the false' also come under the fallacies of the middle term.³ 2 1 Vide Nyayasutra-vrtti, r. 2. 4; Nyayamanjari, p. IIO. 2 In both the old and the modern schools of the Nyaya, the inferential fallacies have been classified under five heads. The first four kinds of fallacies bear the same names or at least the same significance in both the schools. The last kind of fallacy, however, is not only called by different names, but bears substantially different meanings in the two schools. It is in view of this fact that I have taken the two names to stand for two kinds of fallacies of the middle term. Hence we get six kinds of fallacies in place of the five enumerated in the Nyaya treatises. Vide Nyaya-sutra, 1. 2. 4; Tattvacintamani, II, p. 778.) In the Prabhakara Mimamsa the fallacies of the middle term are called the asadharana, badhita, sadharana and asiddha (vide Jha, Prabhakara School of Purva Mimamsa, p. 46). In Pudarthadharmasamgraha the fallacies are called the asiddha, viruddha, samdigdha and anadhyavasita. 3 Vide Tarkabhasa, p. 37.