Nyayasutra 12.17

12.17

iti sūtram | ubhayasādharmyaṃ jñātvāpi yatprakaraṇam pūrvaprayogaḥ sādhanīyaḥ sa pratipakṣāt pratipakṣasādhanāt śrāvaṇatvādeḥ, tatra pratipakṣāt pratipakṣasādhanāt prakaraṇasiddheryattvayā madīyasthāpanāyā bādharūpaḥ pratiṣedhaḥ kriyate tasyānupapattiḥ | kutaḥ, pratipakṣopapatteḥ dvitīyapakṣāpekṣayā pratipakṣaḥ sthā[pa]naiva tadupapatteḥ | yādṛśena hetunā tvayā pūrvaprayogaḥ sādhanīyaḥ tadviśiṣṭenaiva hetunā sthāpanāyā api sādhitatvāt | pratiyoginaṃ dṛṣṭvā pratiyogi nivartate iti nyāyena pūrvasādhyasyaiva vṛtteḥ | nahi gamakarūpāviśiṣṭe'pi prāthamikatvameva balaṃ tadapohya pravṛttatvena uttarasyāpi balavattvāpatteḥ | na cānādau saṃsāre śabdānityatvasādhanaṃ pūrvaṃ na pravṛttamityatra mānamastī[ti] bhāvaḥ | anyathā tvaddṣaṇamasat tatpūrvameva mayā tad viparītasādhanāditi tavāpi doṣāpatteriti |