Nyayasutra 1.4.6

1.4.6

yadyādyaḥ, tarhyasiddhārthatvādīnāṃ pañcānāṃ sādhyasiddhayarthaḥ | guṇānāṃ hetuviśeṣāṇāmaṅgīkāre siddho'sāviti sādhyadharmavattayā dṛṣṭāntaḥ khyāpanīyaḥ syāt | na hi sādhyavikalo dṛṣṭāntaḥ | neti pakṣe na dṛṣṭāntaḥ, na hi śa[asa]makṛtaupathikarūpavattve[he] tu mattvenāsaṃpratipannadṛṣṭāntaḥ, sādhanavaikalyāditi dṛṣṭāntatayā varṇanīyaḥ syāt | tena dṛṣṭāntāvṛttisiddhayarthaṃ guṇadharmavattayā gamakatvamityabhimānena dṛṣṭāntasya khyāpanīyatvāpādanaṃ varṇyasamaḥ | yat kiñcit dharmasāmyena sapakṣasya pakṣatvāpādanaṃ vā varṇyasama iti lakṣaṇam | asyāśca pakṣe vivakṣito hetuviśeṣoddhāraṃ dṛṣṭānto dṛśyaḥ, sādhyasiddhadyaṅga [pakṣasattvādi] pañcakāliṅgito hetuḥ yadi dṛṣṭāntaḥ tadā sādhyavaikalyaṃ, anyathā sādhanavaikalyamiti pratyavasthānāt | taddvārā hetu rvā | yatra yatra heturūpadarśanīyaḥ, tatra sādhyasandehe sādhyaviparītavyāptatvarūpaviruddhatvasandehāt sandigdhaviruddhatvam | atha [rthaṃ] gamakarūpavān hetuḥ pakṣa eva tarhyasādhāraṇyamiti pratyavasthānāt | tadbhrāntiḥ phalam | taddeśanābhāsā ceyam | utkarṣasamaiveyaṃ pakṣadharmāṇāṃ dṛṣṭāntāsaṅganāt | uktyanusāreṇāpakarṣasamā veti caitān [caitayoḥ] sādhanadharmabalenotkarṣasyāpakarṣasya vā prasañjanāt | dṛṣṭāntadāṣṭrāntikabhāvamātrabalena hyatra varṇyatvaṃ tat pratiṣedho vā, na tūktahetubalena | ata evātrāśrayāsiddhi-svarūpāsiddhyādayo vipaścitāḥ, tatra tu viśeṣavirodhaḥ | rtahi hetorūpālambhanamanā sta [stha] yaiva | yadi rūpādyutkarṣāpakarṣābhyāṃ pratyavatiṣṭhate tadā ki vācyam | prakṛtādūṣaṇatvenārthāntaramatānujñānyatarat |