CHĀNDOGYA UPANISHAD · 6.4.5

एतद् ध स्म वै तद्विद्वांस आहुः पूर्वे महाशाला महाश्रोत्रियाः ।
न नो ऽद्य कश्चनाश्रुतम् अमतम् अविज्ञातम् उदाहरिष्यति ।
इति ह्य् एभ्यो विदां चक्रुः ॥

etad dha sma vai tadvidvāṃsa āhuḥ pūrve mahāśālā mahāśrotriyāḥ ।
na no ’dya kaścanāśrutam amatam avijñātam udāhariṣyati ।
iti hy ebhyo vidāṃ cakruḥ ॥

'Great householders and great theologians of olden times who knew this, have declared the same, saying, "No one can henceforth mention to us anything which we have not heard, perceived, or known." Out of these (three colours or forms) they knew all.

F. Max Müller · The Upanishads, Sacred Books of the East 1 (1879)