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• Nobody is more dangerous than he who imagines himself pure in hea
  for his purity, by definition, is unassailable. -- James Baldwin, "Nobody Knows My Name" 1961...
• 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
• Sometimes it is said that man cannot be trusted with the government of himself.
  Can he, then, be trusted with the government of others?" -- Thomas Jefferson (1743-1826)...
• 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....
• No one is fit to be trusted with power. ... No one.
  ... Any man who has lived at all knows the follies and wickedness he's capable of....
• Sometimes it is said that man cannot be trusted with the government of himself.
  Can he, then, be trusted with the government of others?...
• He who does not bellow the truth when he knows the truth makes himself the accomplice of liars and forgers.
  -- French philosopher Charles Peguy...
• The greatest of fools is he who imposes on himself, and in greatest concern thinks certainly he knows that which he has least studied, and of which he is profoundly ignorant.
  -- Shaftesbury...