The Bud of Nyāya 1.21

1.21

apāyānnityaḥ śabda iti | athā'nityatā nityaiva tathā'pi
dharmasya nityatyāt tasya ca nirāśrayasyānupapatteḥ tadāśrayabhūtaḥ śabdo'pi nityo bhavet | tadanityatve tannityatvāyogādityubhayathā nityaḥ śabda iti
sarvabhāvānityatvopapādanena pratyavasthānamanityasamā jātirbhavati | ghaṭena sādharmyamanityena śabdasyāstīti tasyānityatvaṃ
yadi pratipādyate taddhaṭena sarvapadārthānāmastyeva kimapi sādharmyamiti teṣāmanityatvaṃ syāt | atha padārthāntarāṇāṃ tathaiva bhāvepi nānityatvaṃ tarhi śabdasyāpi mā bhūditi nityatvamātrāpādanapūrvakād viśeṣodbhāvanācca viśeṣasamāto bhinneyaṃ jātiḥ | prayatnakāryanānātvopanyāsena pratyavasthānaṃ kāryasamā jātirbhavati
anityaḥ śabdaḥ prayatnānantarīya katvādityukte jātivādyāhaprayatnakāryasya dvairūpyaṃ dṛṣṭam | kiñcidasadeva prayatnena nirvartyate,
yathā ghaṭādi | kiñcit sadevāvaraṇavyapanayanādinā prayatnenā'bhivyajyate, yathā mṛdantaritamudakādi | evaṃ prayatnakāryanānātvādeṣa prayatnena vyajyate śabdaḥ kriyate veti saṃśayāpādanaprakārabhedācca saṃśayasamātaḥ kāryasamā jātirbhidyate | tadevamudbhāvanaviṣayavikalpabhedena jātīnāmānantye'pi asaṅkīrṇodāharaṇavivakṣayā caturviṃśatirjātibhedāḥ pradarśitāḥ | pratisamādhānantu
sarvajātīnāṃ pakṣadharmatvādyanumānalakṣaṇe hetāvevamprāyāḥ pāṃśupātā
bhavanti | kṛtakatvaprayatnānantarīyakatvayośca dṛḍhapratibandhatvānnāvaraṇādikṛtaṃ śabdānupalambhanam | api tvanityatvameva | jātiprayoge ca pareṇa kṛte samyaguttaraṃ vaktavyam | pratīpaṅgātyuttareṇaiva pratyavastheyamāsamañjasyaprasaṅgāditi