O wretched man, wretched not just because of what you are, but also because you do not know how wretched you are!Cicero
Choose a subject equal to your abilities; think carefully what your shoulders may refuse, and what they are capable of bearing.Horace
If a man's fortune does not fit him, it is like the shoe in the story; if too large it trips him up, if too small it pinches him.Horace