You know that you know nothing.
It is good to realize that we truly do not know anything. By being in that state of unknowing, we have the opportunity to investigate and find out the source of this "unknowing" by asking, "Who Am I"?
"Find out that knowledge. That is liberation".
All knowledge that can be gained is relative and transient. It does not solve the mystery of existence. Hence, turn inward and investigate and ask, "Who am I?" that is seeing all this phenomena? -Ramana