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• He who knows only one religion knows none. -- Max Mülle
• He who knows not and knows that he knows not is ignorant.
  Teach him. He who knows not and knows not that he knows not is a fool....
• The demagogue is one who preaches doctrines he knows to be untrue to men he knows to be idiots.
  -- H. L. Mencken (1880-1956)...
• He who knows only his own side of the case knows little of that. -- John Stuart Mill
• An expert is one who knows more and more about less and less until he knows absolutely nothing about everything.
• An expert is one who knows more and more about less and less until he knows absolutely everything about nothing.
• He who knows how to be poor knows everything. -- Jules Michelet (1798-1847)