Related:

• Knowledge is not what the pupil remembers but what he cannot forget.
• What broke in a man when he could bring himself to kill another?
  -- Alan Paton, "Cry, The Beloved Country", 1948...
• When a proud man hears another praised, he feels himself injured. English Proverb
• Nature abhors a hero. For one thing, he violates the law of conservation of energy.
  For another, how can it be the survival of the fittest when the fittest keeps putting himself in situations where he is most likely to be creamed?...
• No man is so foolish but he may sometimes give another good counsel, and no man so wise that he may not easily err if he takes no other counsel than his own.
  He that is taught only by himself has a fool for a teacher. -- Ben Johnso...