Have the courage to be ignorant of a great number of things...
in order to avoid the calamity of being ignorant of everything.

I found the above in a very old book.
Considering such a thing, to be unknowing of many points of knowledge
in an effort to not be considered a know-it-all,
and to not fall into a trap of believing what others think
is indeed quite a feat. Self-monitoring of truth is all important.
What others think you know is not.