Śatapatha Brāhmaṇa ("of a hundred paths") 4.1.3.16

4.1.3.16

sa hovāca | turīyaṃturīyaṃ cenmāmabībhajusturīyameva tarhi vāṅniruktaṃ vadiṣyatīti tadetatturīyaṃ vāco niruktaṃ yanmanuṣyā vadantyathaitatturīyaṃ vāco 'niruktaṃ yatpaśavo vadantyathaitatturīyaṃ vāco 'niruktaṃ yadvayāṃsi vadantyathaitatturīyaṃ vāco 'niruktaṃ yadidaṃ kṣudraṃ sarīsṛpaṃ vadati

He said, 'If they have assigned to me a fourth part each time for my share, then speech shall speak intelligibly only one fourth part!' Hence only that fourth part of speech is intelligible which men speak; but that fourth part of speech which beasts speak is unintelligible; and that fourth part of speech which birds speak is unintelligible; and that fourth part of speech which the small vermin here speaks is unintelligible.