It is known to one who thinks it is not known; one who claims to know it does not know. It is unknown to the knowers and known to the not-knowers.
Kena Upanishad
केनोपनिषद्
मूल श्लोकः
यस्यामतं तस्य मतं मतं यस्य न वेद सः। अविज्ञातं विजानतां विज्ञातमविजानताम्॥
yasyāmataṁ tasya mataṁ mataṁ yasya na veda saḥ avijñātaṁ vijānatāṁ vijñātam avijānatām
KeU 2.3