by Babu C. D | 2018 | 44,340 words
This thesis is called: The validity of Anumana (inference) in Nyaya system. It tries to establish the validity of Anumana through citing its application either consciously or unconsciously in every sphere of human life. Anumana in Nyaya system is the knowledge of any object not by direct observation but by means of the knowledge of a liṅga or sign ...
The knowledge of invariable concomitance or vyapti (vyaptijnana) is an important factor for attaining inferential knowledge. Though there is difference of opinion among the philosophers of different schools in respect of the definition, function and nature of vyapti, all of them are of the view that inference is not possible without the proper knowledge of it and hence it has been considered as a special cause of inference by the logicians.
Five provisional definitions of invariable concomitance:
a. Vyapti is the non-presence of middle term (hetu) in the locus of the non-existence of the major term (sadhya) e.g. the hill is full of fire because it is full of smoke. Here, smoke which is the middle term is absent from all regions outside the region of fire (the major term)
b. Invariable concomitance is the non-presence of the middle term in that locus of the non-existence of the major term which is not the locus of the major term itself. E.g., This is occupied by the ape because it is the tree. Tree is the middle term here and occupied by the ape is the major term.
c. Vyapti is the non-co-presence of the middle term with that reciprocal non-existence whose counterpart abides in the locus of the major term
e.g.; the hill is full of fire because it is full of smoke. Here, smoke is not co-present with anything which is non-existent in reciprocity to fire.
d. Vyapti is the state in which the middle term forms the counter part of that non-existence which abides in the locus of the non-existence of the entire major term e.g., the hill is full of fire because it is full of smoke. Smoke here forms the counter part of the non-existence smoke which abides in the region of the non-existence of entire fire.
e. Vyapti is the non-presence of the middle term in what is not the locus of the major term e.g. the hill is full of fire because it is full of smoke. Smoke here is not represent in anything which is not the abode of fire.
Vyapti does not occur in all cases of smoke with all cases of fire.
There is the concomitance of particular cases of smoke with their corresponding fires. It is observed that there is non-presence of fire of a hill in the locus of smoke of a sacrificial ground. Similarly, there is non-presence of the fire of a sacrificial ground in the locus of the smoke of a hill. Thus, vyapti of smoke and fire does not occur if they occupy different loci. At the same time, if they occupy the same loci, none can deny their vyapti. This kind of vyapti is called vyapti of special forms.
Six definitions of Vyapti of special forms–Vishesha-vyapti
a. Vyapti is the co-presence of the middle term with the major term which is different from the counterpart of that absolute non-existence which does not abide in the locus of the counterpart but abides with the middle term in the latter’s own locus.
b. Vyapti is the co-presence of the middle form with the major term, the locus of which is different from that of the counterpart of the reciprocal non-existence which abides in the locus of the middle term.
c. Vyapti is the connection of the middle term with the major term which is different from the counter part of that reciprocal non-existence which abides in the same locus with the middle term.
d. Vyapti may also be defined as the co-presence of the middle term with the major term when there is no condition attached to the middle term.
e. Vyapti is the co-presence of the middle term with the major term which co-abides with that absolute existence whose counterpart is that which is qualified by the nature of the counterpart of the absolute nonexistence abiding in the same locus with the middle term.
f. Vyapti is the possession of that nature which establishes the connection of the middle term with the major term.
Vyapti involving reciprocal non-existence is a comprehensive one. It is affirmed that among the five provisional definitions of vyapti, the third and the fifth and of the special forms, the second and the third involve reciprocal non-existence. 
The knowledge of vyapti as existing in the subject of inference (paksha) is called consideration. Gangesha, the author of Tattva-Cintamani describes inferential knowledge as a kind of knowledge which is produced through the knowledge of the probans which is qualified by invariable concomitance and which exists in the subject of inference (paksha)
Vyapti can be obtained even from single observation of the coexistence. In the form of inference ‘it has this colour as it has this taste. (etadrupavan etadrashat), the knowledge of vyapti is in the form: this taste is pervaded by this colour (etadrashah etadripavyapyah) of which the taste is a qualificand and the pervasion determined by this colour is a qualifier. From the single observation of the co-existence of a Hetu and a Sadhya in the above inference, the definite knowledge of vyapti is attained.
As Vyapti is ascertained from a single observation of the co-existence of the two, when there is the absence of the knowledge of deviation, the repeated observation cannot be the cause of ascertaining Vyapti due to the violation of the rule; the method of agreement in absence (Vyatirekavyabhicara) Repeated observation sometimes acts as a promoter (prayojaka) in the case of ascertaining vyapti by removing the doubt of deviation 
The observation of co-accompaniment attended with the absence of knowledge of exceptions is the means of apprehending invariable concomitance. E.g. invariable concomitance between smoke and fire. When exceptions arise to this invariable concomitance doubt crops up from two sources, from the suspicion of the condition (upadhi) and sometimes from the recognition of common properties and non-recognition of special properties.
In such cases of doubt, reasoning is resorted to. However, recourse to reasoning (Tarka) is considered as a last resort. Gangesha stipulates that reasoning (Tarka) should follow specific process as cited below:
- Interrogation — can smoke abide without fire?
- Reasoning — if smoke could abide without fire, it would not have been a product of fire.
- Re-interrogation — Is smoke a product of fire?
- Reasoning — if smoke were produced neither from fire nor from non-fire then it would have been a non-product. But it is not so.
- Doubt — smoke then may have been produced either from fire or without a cause.
- Incompatibility — why a person who thus indulges in doubt is nevertheless led onto activity? If one doubts whether an effect may or may not be produced with a cause why does he seek for a fire to obtain smoke and for food to get satisfaction. His own activity indicates that he is well aware of the connection between a cause and its effect. It is incompatibility with his own activity.
All the earlier mentioned definitions of Vyapti can be presented in one form called Comprehensiveness (anuyama). The invariable concomitance involving reciprocal non-existence is a comprehensive one and on account of its shortness to be accepted as the cause of inference. The third and fifth definitions of the five provisional definitions and second and third of the special forms involve reciprocal non-existence.
The Samanyalakshana pratyasatti i.e., supernormal connection through universal has also a prominent role in ascertaining Vyapti. When one says, ‘all men are mortal’, it applies to all men and women in the past, present and future and such knowledge is not possible through sense-object-contact. It is achieved through super normal connection and is accepted by Naiyayikas.
Through this Samayalakshana Vyapti between two objects existing in the past, present and future may be established. The vyapti relation between all cases of smoke and fire cannot be known through ordinary sense perception. When the eco-existence between a particular smoke and a particular fire is known, their corresponding universal i.e., smokeness and fireness, are simultaneously perceived.
Gangesha also accepted the importance of Samanyalakshana in the phenomenon of Vyaptigraha. When vyapti is determined through the perception of probans and probandum, all the cases of probans and probandum are automatically perceived through universals. 
By Samanyalakshana sannikarsha the universal, which has become a qualifier in the knowledge of which the object connected with sense organ is a qualifcand (indriyasamvadhavisheshyaka), all the individual manifestations of smoke existing in past, present and future can be perceived with the help of super normal connection though smokeness existing in a particular smoke.
When a particular smoke, a particular fire and their co-existence are known, the corresponding universals of them like smokeness and fireness are known simultaneously. Through the universals, all individuals having these universals become the object of our knowledge.
Footnotes and references:
History of Indian Logic, pp. 421-422
‐ Siddhantamuktavali on verse 63.