"When people tell me that swearing is a sign of low intelligence or a small vocabulary"
I tend to quote that one line from Inherit the Wind, which I can't really remember
Although it does depend on the characters. Some people just don't swear -- I'll use myself as an example here (granted, this only applies to real life, so ;p)
Anyway, though, I've made note of this when I write. Some chars swear in their minds but not outloud. some in reverse. Some use very specific words to mean very specific (schizotypal :3) things.
I'll also note that the implications of the phrase "fuck you" are astounding. For instance, so much is left open. Who, exactly, is commiting the act? Or what, perhaps, if the person recieving is simply badly undersexed? Could it be taken as a compliment, perhaps, or some sort of consolation?
"Why don't any 19th century and even many 20th century classics use swear words?"
The church. That, and people as a whole swore less back then or something. Alternatively, you're just reading prudish old stuff. I mean, I'm pretty sure Joyce was relatively scandalous. And it's not like Naked Lunch or Lolita are particularly recent, either. If anything, a move towards vulgarity stemmed more from the romanticist... stuff of the 1800's. I think that was the movement? What was I Sing of Myself part of?
"which one will you vote for in the next election?"
Neither. They're sentences. They'd suck at running things.
Oh, and this is an amusing story.
I recently got the Blur album Think Tank. It's a parental advisory album. Here's what's funny. I can't figure out WHY. There's no swearing on it. I'm thinking it's one track that just lists a bunch of drugs -- without glorifying them or anything. Just LISTING them, basically -- and saying something like "Everybody's horny" at somet point. Has america gotten that prudish?
And WTF did the word "cuss" come from? That's a silly word. I mean, say it.
"How do you capture at atmoshere of a rowdy group of 14 year olds and maintain your readers attention? "
It can still hold their attention even if it doesn't make sense to them.