非主張と疑似主張について : ダルモーッタラの視点から

Dharmakīrti states in the Nyāyabindu that a valid thesis (pakṣa) is that which meets the following conditions: (1) it serves only as something to be proven (sādhya); (2) it is wished to be proven by a proponent himself; and (3) it does not go against facts that have been proved through certain accepted means (Nyāyabindu 3.38: svarūpeṇaiva svayam iṣṭo ’nirākrtaḥ pakṣa iti ||). Pseudo-theses (pakṣābhāsa) and the other four kinds of invalid theses (apakṣa) are not accepted as valid (Nyāyabindu 3.54). Moreover, the differences between pseudo-theses and these four kinds of invalid theses have not been fully investigated. The present paper aims to clarify these differences through an examination of Dharmottara’s discussions of these theses, which he develops in his Nyāyabinduṭīkā, a commentary on the Nyāyabindu. Close examination of his statements clarifies the following points:
1. If a thesis does not meet the condition (3) described above while meeting conditions (1) and (2), it is a pseudo-thesis. On the other hand, if a thesis does not meet either condition (1) or condition (2) while meeting condition (3), it is one of the four kinds of invalid theses.
2. The statement of inference consists of three elements: (1) a valid thesis; (2) a logical mark (liṅga); and (3) a corroborative example (drṣṭānta). It is only after inquiring into elements (2) and (3) that a thesis is determined to be one of the four kinds of invalid theses. On the other hand, a thesis is determined to be a pseudo-thesis at the very stage in which it is put forward; elements (2) and (3) play no role in this process.