yathoktaṃ śābare bhāṣye "naivaṃjātīyakeṣvartheṣu puruṣavacanaṃ prāmāṇyamupaiti andhānām iva vacanaṃ rūpaviśeṣeṣvi"ti
As stated in the Śābara-bhāṣya: "In matters of this kind, human testimony cannot attain validity, just as the words of blind people [cannot be valid] regarding specific colors."