When your best friend marries the girl you dated, it's hard to get excited.  When the employee whom you hired gets promoted, leap-frogging over you, you may wish him luck and be polite, but inwardly you'd probably like to put a dagger in his back.  Your neighbor wins the lottery—not you.  How do you handle other people's good fortune?  Are you glad for them, or do you detest their good fortune, wishing it had happened to you?  There's a part of human nature which remains the same, year after year, generation after generation.