The anti-rule of politeness
The rule is actually an anti-rule: it is always possible that you are wrong.
Politeness, according to pragmatics*, used to be thought of as a thing of rules. If you followed the rules, you were considered polite. If you said "thank you" when you were supposed to, said "please" when you were supposed to, said nothing when you were supposed to, and followed the cultural rules, you were polite. This is the standard way we think about politeness, of course, both when we teach it to children and when we enter cross-cultural situations where communication's hidden rules seem obvious.
This old idea had two problems, though. First, it couldn't account for over-politeness, situations where, by following the rules, meticulously and excessively adhering to the please-and-thank-you conventions, politeness itself becomes rude. Second, it couldn't account for the instability of politeness, the way that it's always possible for politeness to be taken as impoliteness.
Consider what happens when a designer is eliminated from the show Project Runway. Heidi Klum announces the judges' pronouncement, "you're out," and then, in proper German, says, "auf wiedersehen." This is the German farewell most Americans know, but it is actually too formal for everyday use. You don't, today, at least in Southern Germany, say auf weidersehen to a friend or someone you know. Except possibly as an overly formal, jokey farewell, what you would say to a friend would be Tschüß or ciao or schönen tag! Though the formal farewell literally translates as something like "until we see each again," it's formality or over formality could imply, in the context of Project Runway eliminations an over-politeness. It can be taken as a rude dismissal, the kind of very formal brush-off an official gives to someone who has no social standing. The rudeness or possible rudeness of Klum's farewell is seen in some promotions of the show, which ask, in a Denglish pun, "Who will be Auf'd next?"
Of course, most of the designers, in the seasons of the show I've seen, don't take the auf wiedersehen to be impolite. Many of them actually try to respond with auf wiedersehen too. The phrase doesn't seem impolite because it isn't taken as impolite. Regardless of the rules of politeness there may or may not be for a word in Germany or America or on TV, it's not impolite when it's not taken as impolite, though this also means the reverse, that no matter how polite something is intended to be or how closely it aligns with the articulated or unarticulated rules, it's only polite if the hearer hears it as polite.
Politeness, according to pragmatics, is now understood not to be about rules at all, but a matter of the hearer's evaluation.
This means a negative evaluation is always possible. There is nothing the speaker can do to foreclose the meaning of a remark. There is no court of appeals of politeness, no rule that can act as neutral judge in negotiating a dispute between people. If something is taken as impolite by a hearer, the speaker cannot insist that the hearer is wrong and it really was polite, but must appeal to the hearer to hear it a different way. (If the speaker refuses to recognize the hearer as the evaluator of the statement, of course, and insists the hearer has no right to say what it was that was said, then the rudeness is compounded by rudeness).
There are two direct connects here to Continental Philosophy: first to Hegel's idea about the master and the slave, where the master is actually slave to the slave and the hierarchy is unstable, and second to the Levinasian idea that ethics originates with infinity of the Other, and one must recognize the uncontainable, un-closable alterity of the Other, glimpsed in the face of the Other, who has a freedom and an authority (even, re:Zizek, a terrible, frightening power) that one can only be humble before.
What interests me especially here is that pragmatics, through a study of language, has come to same conclusion or kind of conclusion as Continental Philosophy after the ethical turn. As Rene Girard might put it, it is an issue of humility. One cannot force someone to accept what one says as polite; instead one has to actually give up the claim to being right, submit, he might even say, one to another, readily recognize and cede to everyone else's claims, always being willing or ready to admit that one is wrong.
The only way to be polite and the only way to be ethical is to be always ready or willing when asked to apologize.
And isn't this the basic, ongoing struggle in American cultural the goes under that name "political correctness"? Conservatives feel they're following the rules of the dominant culture but that that's being held against them and that they're being forced to submit to minorities' demands. Which, in a way, they are. Which is, in fact, the only way to be ethical, and the only way to be polite. Insisting on the rules results in the weird situation where, supposedly in the spirit of Christmas, people get belligerent in wishing everyone Merry Christmas, as if Christmas could be forced on people who don't want to celebrate it.
There is this frustration, of course, that one can't know whether, for example, a white person should say "black" or "African American," or whether a man should or should not hold open a door for a woman, that there is no rule that one can follow and always be right. That frustration is understandable. We want there to be a rule to which we can appeal, but we only have each other. We want there to be a rule by which we can guarantee with some certainty that we're right and by which we can be justified.
It doesn't work that way though. The only rule we have is this anti-rule, we have to be humble, because it's always possible we're wrong.
* Thanks to Annick Paternoster and Christiana Gregoriou, both of the University of Leeds, for telling me about the developments of ideas of politeness in pragmatics. Any misunderstandings or misrepresentations of ideas within pragmatics, however, are most certainly my own.