Related:

• An Animal that knows who it is, one that has a sense of his own identity, is a discontented creature, doomed to create new problems for himself for the duration of his stay on this planet.
  Since neither the mouse nor the chip knows what is, he is spared all the vexing problems that follow this discovery....
• He who beleives in nobody knows that he himself is not to be trusted.
• Man is the only one that knows nothing, that can learn nothing without being taught.
  He can neither speak nor walk nor eat, and in short he can do nothing at the prompting of nature only, but weep....
• The truly proud man knows neither superiors or inferiors.
  The first he does not admit of -- the last he does not concern himself about. -- William Hazli...
• A censor is a man who knows more than he thinks you ought to. -- Granville Hicks (1901-1982)
• The world steps aside to let any man pass if he knows where he is going. David S. Jorda
• He is a man capable of turning any colour into grey. -- John LeCarre
• It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better.
  The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood, who strives valiantly...
• 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....