Commentary on the Nyāyasūtra 11.2.p13

Nyāyabhāṣya (complete text) 11.2.p13

nanu sāmīpyasya sādṛśyasya mānaṃ mitiḥ saṃjñāsaṃjñiparicchede pramāṇamityukte kuto vyāghātāvakāśa ityata