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• It is almost as difficult to make a man unlearn his errors as his knowledge.
• From the errors of others a wise man corrects his own. -- Publius Syru
• While the gentleman cherishes benign rule, the small man cherishes his native land.
  While the gentleman cherishes a respect for the law, the small man cherishes generous treatment....
• A man of genius makes no mistakes. His errors are volitional and are the portals of discovery.
  -- James Joyce, "Ulysse...
• If you would know a man, observe how he treats a cat.
• If you would know a man, observe how your cat treats him.
• It is only the benevolent man who is capable of liking or disliking other men.
  -- Confucius, Analects, IV.3...
• Nature understands no jesting. She is always true, always serious, always severe.
  She is always right, and the errors are always those of man. -- Goethe...