Note: in my discussion of the concepts underlying profanity, I mention things that are profane. If you're a child, or you can't handle that, stop reading. A recent story at Ars Technica about the an appeal in a case of the FCC vs. foul-mouthed celebrities on television sparked a discussion of profanity and censorship, to which I contributed. The "rule" in question is the de facto prohibition on broadcasting the "seven deadly words"on the limited community resource known as the broadcast spectrum. The article critically mentions the solicitations of complaints, not only from those who witnessed the alleged profanity in question in its full context, but those who merely heard about it, and were members of the relevant community concerned about the use of the public resource. Again, here is the article, and my comments are below:
I can understand (and in part, support) those who complain even though they themselves did not witness the broadcast profanity.
If the rule becomes subjective, then the subjectivity of the rule (in stead of the rule itself) will become the new line against which those who produce content and wish to call attention to said content will push. This includes celebrities, who are their own brand, calling attention to themselves for being 'uninhibited' (the kids these days think that's hip).
The argument is that allowing some profanity and saying "that's OK" is a slippery slope to all profanity falling within that category.
The reason profanity is profanity is that (with the original linguistic intent) it evokes an image that is intended to repulse the listener (i.e., it is profane).
The word "fuck", for example, doesn't merely denote sex: it denotes sex of a most detestable kind: forced and devoid of love (and therefore by its very nature, an insult to the true intent of sexual love).
The same can be said of "shit". Shit isn't just excrement, it's a forced confrontation with excrement: it's thrown into your face, or you are thrown into it. In other words, "shit" is an insult to human dignity (though admittedly, not as much so as "fuck", which associates marital bliss with sadistic rape).
These words have, in some quarters of our collective culture (but certainly not all), undergone a change in meaning because of over-use. When a teenage girl says that she is "majorly depressed", she is likely to be merely sad, but she is using exaggerating language because she does not think that others will give her "anguish" the attention and respect that at the moment she feels it deserves unless she oversells it.
Gradually, though more rapidly in communities that tend to over-express (such as the young and the marginalized) terms of extremity become watered down, until eventually they have no meaning at all, and new words must be invented to fill the voids of extremity.
The process of the erosion of words so that they mean less than they did originally (or, equivalently, less to some than others) is an unfortunate aspect of the evolution of words because it makes language less reliable and less useful.
There are other linguistic evolutionary processes that are beneficial (such as specialization and connotation), but the watering down of terms is not one of them, and I believe it should be resisted.
If those who use the word "fuck" for shock value suddenly discovered that the term had become watered down to meaninglessness, the next logical place for them to reach would be to shout "sadistic rape!" every time they chipped a nail.
I do not wish it to be necessary to explain the meaning of that term to my kindergartener.