KENA UPANISHAD · 2/3
यस्यामतं तस्य मतं मतं यस्य न वेद सः ।
अविज्ञातं विजानतां विज्ञातमविजानताम् ॥
yasyāmataṃ tasya mataṃ mataṃ yasya na veda saḥ ।
avijñātaṃ vijānatāṃ vijñātamavijānatām ॥
He by whom It is not thought out, has the thought of It; he by whom It is thought out, knows It not. It is unknown to the discernment of those who discern of It, by those who seek not to discern of It, It is discerned.
Sri Aurobindo · CWSA 18, p. 7