Commentary on the Nyāyasūtra 11.4.p31

11.4.p31

tathā hi nopahitasya niścita eva sādhyavyabhicāraḥ, upādherlakṣaṇaṃ kiṃ nāma? sādhanāvyāpakatve sati sādhyavyāpakatvam| tacca sādhyābhimatadhūmaśyāmatve prati vyāpakatvem ārdrendhanānnapānapariṇatibhedayoraviśiṣṭam, aviśiṣṭaṃ ca sādhanābhimatadahanamaitratanayatve prati tayoravyāpakatvam| iyāṃstu viśeṣaḥ, vahnerdhūmenevārdrendhanenāpi sākṣādeva vinābhāva upalabhyate| maitratanayasya tu śyāmatvenevānnapānapariṇāmenāpyupādherevonnīyata iti| nanu vajre lohalekhyatvaṃ prati pārthivatvahetoḥ ka upādhiḥ? praśithilāvayavatvam| tarhi tannivṛttau paveriva sphaṭikādāvapi lohalekhyatvanivṛttiprasaṅgaḥ| na khalu nibiḍāvayavatvena ubhayoḥ kaścid viśeṣaḥ| na mṛdādibhyo nibiḍāvayavatve'pi sphaṭikasya praśithilāvayavatvādeva| na hyadbhyo medinī nibiḍeti na praśithilāvayavā| iyāṃstu viśeṣaḥ| yathā yathā śaithilyāpakarṣastathā tathā lekhituḥ prayatnaprakarṣaḥ| yadi tu śaithilyamaprayojakaṃ tadā mṛtkāṣṭhapāṣāṇādiṣu prayatnaprakarṣo'pi viphalaḥ, pārthivatvasya sarvatrāviśeṣāt| sphaṭike kathameṣā pratipattiriti cet? lohalekhyatvādeva| lohalekhyatvapraśithilāvayavatvayoḥ samavyāptikatvāt| ata evānayorekatarapravṛttinivṛttyorevānyatarapravṛttinivṛttī, na tu pārthivatvapravṛttinivṛttyoreva lohalekhyatvapravṛttinivṛttī, vajre'darśanāt ; jalādau darśanācca| vahnāvanuṣṇatvasādhanasya tu kṛtakatvasya tajjātīyetaratvalakṣaṇamupādhiḥ, sa ca bādhaikaniyataviṣaya iti nātiprasaṅga ityuktam| tadetatsarvaṃ hṛdi nidhāyāha---ityādaya iti||