The system of Kanaada was later combined with the system of Nyaaya and became one system. It is called Navya – Nyaaya or Tarka Saastra.

Although in the earliest stages of their inception the schools of Nyaaya and Vaiseshika held independent positions both in epistemology an metaphysics, it was recognized from the very beginning that the two schools had very much in common and that their differences were of minor importance. The later fusion of the Vaiseshika metaphysics with the Nyaaya epistemology was not an arbitrary or unnatural attempt at a rapprochement, but was dictated by an inner logical necessity of giving a complete philosophy of realism, with the deficiencies of each made good in a well-rounded synthesis. Though the professed objective of both the systems is to provide a clear cut formula for the achievement of salvation and freedom from the limitations of personal existence, this ultimate problem of salvation is forgotten and shoved into the back-ground, for the time being, in the zeal for philosophical speculations.  Of the 16 Padaardhas of Nyaaya, only the first one, namely Pramaana-the approved sources or instruments of knowledge received the most elaborate consideration at the hands of Gangesa in his Tatwa-Chinaamani, which forms the main foundation of Navya – Nyaaya. Laterly, the interests of Navya – Nyaaya in Nadia (Navadweepa) were accordingly of the nature of epistemological enquiries, and the interests in metaphysics were purely of subsidiary character. The main energies were directed to questions of practical importance such as proper guidance of philosophical debates. * Metaphysics is the science that seeks to know what it is that really exists. It embraces Psychology. Ontology and Epistemology. Psychology is that branch of knowledge, which deals with the human soul (psyche): also that knowledge of the mind, which we derive from a careful examination of the facts of consciousness; the natural history of the mind. Ontology (entos being): The doctrine of being. That part of metaphysics, which investigates and explains the nature of all things or existences, treating of whatever does and can exist. Epistemology (episteme – knowledge) The theory of the method or ground of knowledge.The words ontology, epistemology and metaphysics are often used synonymously.SYNTHESIS OF NYAAYA AND VAISESHIKA.In the course of developments, the Nyaaya and Vaiseshika schools were wedded into one system and produced a well rounded compact and consistent philosophy. The four Pramaanas of the Nyaaya system were accepted by the Vaiseshikas and the six padaardhas of the Vaiseshika system were accepted by the Naiyaayikas.The prestige and honour which Nyaaya philosophy enjoys in the present day are entirely due to this happy synthesis of Vaiseshika metaphysics and Nyaaya epistemology, which made this branch of philosophy fuller, richer and more consistent. The Vaiseshika philosophy is poorer in its epistemological interest and is pre-eminently metaphysical, and contrariwise Nyaaya is pronouncedly lacking in its metaphysical interests and its strength lies in its logical and epistemological necessity. A combination of the two was a logical necessity. 

A Survey of its Epistemology

Nyaaya philosophy grew in is strength and volume in consequence of its fight with rival Buddhistic schools. Gautama’s epistemology and logic as developed by Vaatsyaayana in his Bhaashya were mercilessly attacked by Dinnaaga (Buddist) and their prestige suffered a rude shock. This gave the occasion to Uddyotakara to write his Nyaaya-Vaarttika. Uddyotakara in course of his comments criticized Vasubandhu and dinnaaga and defended the Nyaaya position. Dharmakeerti, Dharmottara and others took up the challenge and showed the weakness and inadequacy of Uddyotakara’s defence. Next came – Vaachaspati Misra who again gave replies to the animadversions of the Buddhist philosophers and the defence of the Nyaaya school of thought was carried forward by Jayantabhatta, Sridhara and Udayana. After Udayana we do not hear of any Buddhist philosopher who caused trouble to orthodox systems. Even a survey of the works of these writers will convince the reader how keen and acute was the fight that was carried on between the **twisted schools of thought. The result was precision of definition **on which every word, and every particle, was duly **measured had to be defended. Nyaaya in one sense came to be regarded as the science of definitions, the importance and necessity of which are now coming to be recognized in modern European philosophy on account of the attacks of Neo-Realists of Europe and America. Every concept has been accurately defined and there is no room for doubt or speculation as to the meaning and purpose of the philosophical arguments. Clarity of thought and accuracy of expression have become the characteristic features of works on Nyaaya philosophy and of other schools as well owing to the preponderating influence of Nyaaya speculations on the course of philosophical thoughts of India.           

It is not a matter of surprise therefore that the scholarship of a student of Indian philosophy of whatever school it may e is looked upon with scepticism unless he can produce a proof of his acquaintance with the Navya Nyaaya speculations. 

The greatest achievement of Gangesa consists of the marshalling of the arguments of all previous writers in his work with an accuracy and ingenuity which evoke spontaneous admiration. In a short compass he has given as the best and solidest fruits of the labours of past masters and focusses the attention of the student on the most fundamental and characteristic contributions of the school. Naturally this work alone has come to monopolize the attention of later students and commentators. 

Gangessa’s main purpose is to treat of the four Pramaanas-Pratyaksha (perception), Anumaana (inference), Upamaana (comparison) and Sabda (verbal testimony).     

It is on the chapter of inference (anumaana) that Gangest and the later writers have shown their best ingenuity. The conditions of inference have been thoroughly analised and explained. Inference is defined to be the judgement produced by the knowledge of the minor premise (Paksha-dharmata) qualified by the knowledge of the universal proposition (Vyaapti) the major premise, which states the connexion between two terms in their universal reference. This universal connexion is termed Vyaapti and a long discussion of the concept of Vyaapti and its diverse definitions is undertaken. 

This chief value of Nyaaya philosophy consists in its contributions to method and terminology, which have been invariably adopted by all other schools of thought. The consequence has been that whatever school of thought one may follow and whatever may be one’s philosophic **predilections and convictions, one must speak in the language of Naiyaaykas. 

Hetwaabhaasa (Fallacies)

[*The following extracts on fallacies are taken from the valuable contribution of Sri Satkavi Mukharjee M. A. Ph. D. Lecturer in Sanskrit, Philosophy and Pali… Calcutta University the Cultural Heritage of India-Ramakrishna Matt.

Compare Charaka’s classification-Vimaana Ch. 8.] 

The Indian logician has furnished the evidence of his penetrating insight and critical observation and his findings will be hailed as astonishingly original contributions, when dealing with fallacies Hetwaabhaasa. The study of fallacies in standard works on logic has been a favourite and useful pursuit from very old times both in Europe and India. Perhaps the necessity of exposing fallacies in the arguments of the opponent proceeded from the systematic and scientific study of logic as a separate science and discipline. Many of the fallacies treated of in standard works on European logic are not fallacies of inference and they have been set apart in a different category by Indian logicians. The Nigrahasthaanas (grounds of defeat) are rightly believed to form a wider class which comprehends logical fallacies (hetvabhasas) in their scope as a particular variety and were never confounded with purely logical aberrations. The fallacies, which have been called fallacies in diction by Aristotle and which have their origin in ambiguity of language, are not regarded as fallacies proper by Indian logicians and they have been judiciously placed under the head of Chhalas (quibbles). Many of the fallacies of the extra dictionem variety also are not regarded as fallacies of reason and they may be placed either under the head of quibbles or that of nigrahasthaanas, which are symptomatic of other than logical delinquency. The fallacy of ignoratio elenchi, which consists in proving another conclusion than what is intended, will be subsumed under the head of arthaantara, a variety of nigrahasthaana, which serves to show that the arguer has no clear grasp of the issue. Hetvaabhaasas or false reason are precisely those fallacies in middle terms which when discovered are found to lack any bearing on the conclusion sought to be drawn. A study of fallacies in a work on Logic is justified on the ground that it contributes to the discovery of truth or defeat of the opponent by creating a habit of mind to avoid or to discover the flaws in our reasoning. 

A hetvabhaasa is defined to be a false probans (middle term) the discovery of which works as a deterrent towards inference; in other words, it is what makes inference impossible and illegitimate. A hetvaabhaasa may be regarded either as a false reason (heta) or a defect visiting the reason. Whichever view may be taken of the nature of a hetvaabhaasa the undeniable fact remains that the concept of hetvabhasa (fallacy) does not extend to any defect or shortcoming or a personal nature and strictly stands for those objective defects alone which obstruct the process of inference. Previous conviction of the conclusion is an obstacle to inference and according to the definition it should be regarded as a case of fallacy. But that is not the case. Concept of fallacy does not include the cases which serve as impediments to inference only under definite conditions and cease to function as deterrents when those conditions are removed. A previous knowledge of the conclusion does not operate as a bar to inference when it is accompanied by a desire for inferential proof of the otherwise known thesis and so it does not fall under the category of a fallacy. The definition, however, covers the accredited cases of recognized fallacies which according to the Naiyaayika are of five different types, viz (1) analkaantika (the inconclusive probans (middle term) lacking invariable concomitance with the probandum (major term): (2) viruddha (the contradictory probans which is invariably concomitant with the absence of the probandum: (3) asidha (unproven probans); (4) satpratipaksha (the counter-balanced probans) and (5) baadhita (the contradicted probans). The inconclusive (analkaantika) probans thwarts the process of inference by violating the universal concomitance (vyaapti), which is one of the conditions of inference. The frustration of inference may be direct or indirect through the violation of the conditions of inference. Now, the conditions of inference are (i) the universal concomitance of the probans with probandun: (ii) the subsistence of such probans in the subject – which is expressed in the minor premise. The combined product of the two premises is the synthetic judgement (paraamarsa) which immediately leads to inference of the conclusion. If by reason of any defect the synthetic judgement fails to materialize, the conclusion will not follow and a deadlock will be the result. 

Anaikantika