To discover the meaning of this divine utterance, Socrates questioned a number of men who laid claim to wisdom—politicians, poets, craftsmen—and in each case concluded, "I am likely to be wiser than he to this small extent, that I do not think I know what I do not know."
Socrates was the wisest of all people not because he knew everything or anything, but because he knew what he did not know—or, more subtly, because he knew the limits of the little that he did know. In fact, the world really came together in the 5th century BC, with both Confucius and the Buddha echoing from afar the words of Socrates.
'Real knowledge is to know the extent of one's own ignorance." Confucius
"A fool who recognizes his own ignorance is thereby in fact a wise man.' Buddha
Before Shakespeare put it straight, "The fool doth think he is wise, but the wise man knows himself to be a fool."
Books are a path but there are none on the other side of the gate.