1. Introduction: Historical overview

[Full title: Historical overview of the conflict between the school of Buddhist logic and the Nyāya]

The perceptual process plays a foundational role in giving us knowledge about the external world. Sense-perception is invariably taken as the principal among all the evidential means, for, all the means are, in some way or other, preceded by sensory perception, and must be, in the long run, authenticated by some sensory perceptual base. Of course, in accordance with the difference in world-views, different Indian philosophical systems do not consider that perceptible entities are of the same type. For example, the Nyāya system considers that we perceive physical objects directly, and not through a veil of sense-impressions. This principle in combination with the thesis that the world is exactly as we know it in our normal perception and inference, yields a world-view that is physicalistic in the sense that the elements are physical items such as things and properties, parts and wholes. They choose the observable physical elements, consisting of the things and properties, and hence their programme is to explain the phenomenal in terms of the physical. The Nyāya wishes to defend a common-sense version of realism, for it qualifies the ordinary physical things with visual, tactile, and other properties. The Buddhist, on the other hand, prefers the phenomenal object and argues that nothing beyond the phenomenal need be accepted, for we can explain everything in terms of the phenomenal. The dharma doctrine of the Abhidharma can be seen as an attempt to carry on this programme of explanation. In this view, actual sensory perception is the non-conceptual and indubitable cognitive experience. The choice of one rather than the other type of elements as basic reflects a difference in the philosophical motivations of the Nyāya and the Buddhist.

The Nyāyasūtra of Akṣapāda Gautama and the Bhāśya of Vātsyāyana show the influence of Buddhist critics like Nāgārjuna and refute some of their charges. Diṅnāga then sets himself to criticizing Brahmanic doctrines as those of Akṣapāda and Vātsyāyana. To answer the objections of Diṅnāga, Uddyotakara writes his Nyāyavārttika. Brahmanic criticism on Diṅnāga similarly influenced Dharmakīrti to write the Pramānavārttika-kārīkā, a matrical commentary upon the Pramāṇasamuccaya effecting all possible improvements in their own defence. Dharmakīrti was again answered by Vācaspati, the great Brahmanic philosopher and commentator. Dharmakīrti was succeeded by a number of Buddhist logicians like Devendrabodhi, Vinītadeva, Jinendrabodhi, Śāntirakṣita, Dharmottara, Arcaṭa and Jetāri, many of whom wrote commentaries and sub-commentaries on the treatise of Diṅnāga and Dharmakīrti and occasionally criticized Brahmanic writers like Kumārila and Vācaspati. But they did not possess much originality of thinking like the two masters: Diṅnāga and Dharmakīrti. Owing to these common conflicts and opposition Indian Logic had the opportunity of developing by a process of alternate criticism and construction.

The continuity of Buddhist logic came up to about 1000 A.D. when the decline and fall of Buddhism in India sounded its death knell. During this time with the revival of Brahmanism Brahmanic logic being tinctured with Buddhistic influence came to be studied over again and thus was laid the foundation of the new school of Brahmanic logic Navya-Nyāya which flourished later on so luxuriantly in Mithila and Nadia.