古典ニャーヤ学派のアートマン論とその背景 (第五百號記念特集號)

Abstract

The early Naiyāyikas, who were primarily concerned with the investigation of the method of discussion (vāda), tried to incorporate the doctrine of liberation (adhyātmavidyā) into their system by dealing under the category 'objects to be known'(prameya) with those topics which are related with transmigration and liberation. The ātman is recognized by them as one of the 'objects to be known'. Through various arguments, the Naiyāyikas proved the existence of ātman, which synthesizes the experiences of body, sense-organs and mind, subsists unchangeably from past life to future life, and becomes receptacle of the fruits of past deeds. It is known that the Naiyāyikas established their system on the basis of the natural philosophy of the Vaiśeṣikas, which originally was formed in the milieu of heterodoxy where materialistic, deterministic and animistic views were prevalent. While proving that there exists the everlasting ātman, the Naiyāyikas made attacks upon the materialist and Buddhist views, and we see in their arguments that they came to be harmonized with the main current of Indian thought. However, the Naiyāyikas confined their view to the empirical aspect of the ātman: the universal ātman, the knowledge of which led the Upaniṣadic philosophers to final liberation, was totally unfamiliar to them. In this respect they differed essentially from the Vedāntins and the Sāmkhyas, who, following the Upaniṣadic tradition, regarded the ātman as being transcendent of all phenomena, and whose systems were permeated with the doctrine of liberation. For the Naiyāyikas, there was no discrimination between empirical knowledge and liberating knowledge, both being attributed to the same ātman. Although the Naiyāyikas asserted that the liberation is attained through the true knowledge of the 'objects to be known', we find that their system was merely in the guise of the doctrine of liberation.