Hidden agendas
I wonder about three aspects of derogatory words, in addition to the issue of whether somebody deserves condemnation.
First, it is logically offensive to criticize a person by criticizing his group--unless the group truly deserves insults (like Nazis or thieves), and the person shares their shame or guilt. It would be wrong to call a politician a Nazi for things that are not Nazi-like--but appropriate for things that are.
其次，从逻辑上讲，为了避免伤害人们的感情而避免真实的批评是一种冒犯。如果一个政客做了纳粹的事情，我们应该指责他或她，即使这会伤害感情。这并不意味着我们应该总是监督人们的错误——只是说，如果我们认为有必要直言不讳，逻辑上并不禁止我们直言不讳。
This point is sometimes lost in law. Sexual harassment, for example, is one of the few laws that is defined by what the victim thinks (if a woman feels harassed by an action, she is). We would never determine assault and battery by what the victim thinks or feels--there must be overt visible action that everybody of sound judgment would call assault and battery.
所以我们必须禁止冒犯他人的词语，不管他们是否应该被冒犯?在大多数场合，我们知道什么话是冒犯大众的，但在公共场合，我们并不总是知道这一点。这就是为什么可能会张贴标语，禁止亵渎或粗俗，因为那里可能有很多人(例如，儿童是允许的)。这是一个礼貌问题——不是法律或道德问题——但因为在某些情况下它会影响到一个办公场所，所以它也是一个经济问题。我们不希望有人抢走我们的好客户。法律对此提供了一些支持。道德在这一点上的唯一支持是，道德要求我们尽我们最大的能力对他人表示尊重，而侮辱(如果不是应得的)并不能表示尊重。
And the third question is whether it is immoral to use derogatory language at all (when it is not justified). The hinge of reasoning here falls upon the word "justified." I am justified in calling somebody a murderer if he or she is one (though that does not entail that I must bring it up). Am I justified in calling someone who killed a deer a murderer? I would say no. Or someone who killed by accident? Again I would say no.
Consider the N-word, or the others listed above for Jews, or for Puerto Ricans, etc. I consider it morally relevant that there is never "justification" for these words, because they do not attribute anything morally interesting to the victims. They are meant only as an insult (though why they are insulting is cloaked deep in the history of the words). If the n-word, for instance, only meant "black-person!" why would that be an insult? If it meant, "low-down, no good black person," then it would be an understandable insult--but nobody wants to ban that language, because sometimes it is true.
Is it that the n-word is never sometimes true? As African Americans use the term, I think that sometimes it is true (as the word "murderer!" can sometimes be true). As white people traditionally used it (low class southern white people), it was a term that carried no crimes or immorality with it, yet was meant as an insult because it associated a belief in inherited inferiority with the group. So the insulting false-accusation (that makes it unfair and therefore not moral) is that it carries these hidden false assumptions.
(注意——我在融合前的孟菲斯长大，我们被教导不要使用n字，因为那是低级语言，这是足够的道德理由。)
p.s.
This conversation does not address the weird logical problem that referring to a word should never be confused with using the word. If I "use the n-word" on the witness stand to say what the accused really said, I am not in the logical sense "using the word" myself--I am merely referring to it. But we have got used to being confused about the logic of it, and came up with "the n-word" as a way of referring to it without using it. This assumes that people know what "n-" stands for (but logically we can never tell them).

My question is why we have forbidden words in the first place. Yes, it's obvious that common civility and a desire for harmony tend to preclude the use of such things as the N-word, the K-word, the C-word, and so on. They are almost universally considered insults. But why is "fuck" forbidden, or "shit"? I can say "sexual intercourse" or "excrement" or any of a number of other synonyms, but why are these simple words - mostly of Saxon origin, I think - so widely thought of as unacceptable? My own theory, not based on much evidence, is that it is a class thing. Using these words indicates a lower class origin and they "must" therefore not be used.
也许，真正的问题是，为什么我们需要禁忌语。禁止它们的社会目的是什么，换句话说，谁来决定它们是什么，它们应该继续被禁止?我说"去他妈的这些自以为是的道德仲裁者"还是说这也是被禁止的?