Commentary on the Nyāyasūtra 2.20

2.20

tatra vādajalpau saprayojanau/ vitaṇḍā tu parīkṣyate/ vitaṇḍayā pravartamāno vaitaṇḍikaḥ/ sa prayojanam anuyukto yadi pratipadyate so 'sya pakṣaḥ so 'sya siddhānta iti, vaitaṇḍikatvaṃ jahāti/ atha na pratipadyate nāyaṃ laukiko na parīkṣaka ity āpadyate/ athāpi parapakṣapratiṣedhajñāpanaṃ prayojanaṃ bravīti, etad api tādṛg eva/ yo jñāpayati yo jānāti yena jñāpyate yac ca jñāpyate etac ca pratipadyate yadi, tadā vaitaṇḍikatvaṃ jahāti/ atha na pratipadyate, parapakṣapratiṣedhajñāpanaṃ prayojanam ity etad asya vākyam anarthakaṃ bhavati/ vākyasamūhaś ca sthāpanāhīno vitaṇḍā, tasya yady abhidheyaṃ pratipadyate, so 'sya pakṣaḥ sthāpanīyo bhavati/ atha na pratipadyate, pralāpamātram anarthakaṃ bhavati, vitaṇḍātvaṃ nivartata iti/
atha dṛṣṭāntaḥ pratyakṣaviṣayo 'rthaḥ, yatra laukikaparīkṣakāṇāṃ darśanaṃ na vyāhanyate/