Related:

• He who knows nothing, knows nothing. But he who knows he knows nothing knows something.
  And he who knows someone whose friend's wife's brother knows nothing, he knows something....
• He who knows how to be poor knows everything. -- Jules Michelet (1798-1847)
• I taught him everything he knows!
• A truly wise person knows that he knows not.
• He who knows others is clever; he who knows himself is enlightened.
  -- Lao-tzu, Chinese philosopher and founder of Taoism...
• He who knows others is wise. He who knows himself is enlightened. -- Lao Tsu
• The demagogue is one who preaches doctrines he knows to be untrue to men he knows to be idiots.
  -- H. L. Mencken (1880-1956)...