Rule #6: A person, who is nice to you but rude to the waiter, is not a nice person.
I got this rule from my communication teacher freshman year. He explained to us if we ever wanted to test the character of a person, take them out to dinner and see how they treat the waiter. It will tell you a lot about their personality. If they treat the waiter nicely, then they are genuinely a nice person, but if they treat the waiter poorly then they are being nice to you for less than genuine reasons. One of my favorite quotes is “Character is how you treat those who can do nothing for you.”