A Friend-Foe Letter to my Grandchildren

Dear Grandchildren: You all have friends, and some of them are mutual (shared) friends. Your personal friend in Edmonton cannot be a mutual friend of one who lives in Redlands, unless that friendship was made while you were at your Convention. You all have enemies, and sometimes they might be mutual enemies. What I am about to tell you is that you, indeed, do have a Mutual Enemy. What is a friend? It is a well-wisher, a supporter; it is one who is attached to another by feelings of personal...