It brands you as an aggressive, uneducated person, and it offends more people than you think: These are the consequences of swearing in public.
But according to Dr Melissa Mohr, using obscenities "can relieve pain and frustration" and, in certain circumstances, may even express joy. Either way, she says, swear words "really fulfil a function that people have found necessary for thousands of years".
Swearing is never value-neutral. But it does not signify the end of civilisation either, for what may be regarded as a dirty, vulgar expression today was once a perfectly good word and could become respectable again. Documenting how swear words change their meaning and "shock values" is Dr Mohr's objective in a book which manages to be both erudite and entertaining.
As befits a scholar of Renaissance literature, Dr Mohr is especially strong in narrating English language obscenities from the 15th century onwards. But she does a good job too in looking at the Romans, who used some very explicit swear words more than 2,000 years ago.
The exercise of piecing together how the Romans swore at each other is not just an arid academic pursuit, for it impacts on our use of English today. Essentially, the Latin words Romans regarded as obscene are now viewed as utterly prim and proper. Go to a doctor or listen to a sex education lecture in a classroom, and it's guaranteed that you'd hear sexual organs referred to by their Latin terms.
"They are almost abstractions, going as far as words can to de-sexualise the things they represent", Dr Mohr explains. But the reality is that "penis" was a major obscenity to the Romans, while "vagina" was an even coarser Roman metaphor for the anus (in itself another Latin word).
In the Middle Ages, when Europe was in the tight grip of Christianity, one was deemed to have dishonoured the Almighty by uttering "Oh, my God" or "by God". What's more, "by God's bones" and "by God's nails" were believed to actually injure the body of Christ.
Today, "my God" is what every English-speaking kid says on average every 30 seconds.
As religion gradually lost its importance, the universe of profanities expanded to include sexual organs or bowel movements. Again, these words were not considered obscene a few centuries ago, since most Europeans neither enjoyed nor expected privacy. It was quite common to see people defecating in public, so it was no big deal to refer to what they excreted. But when the demand for privacy grew, so did prudishness. By the 19th century, the very mention of body organs or functions was considered the height of obscenity.
And so it remains.
Still, the wear and tear of language use applies to profanities as well. "S**t" is no longer as shocking; it now "hits the fan", "lands" people in it and is even "holy". "D**k can now be a term of endearment, as in "don't be a d**k". "P**s" can mean many things, including being angry or drunk. Sexual organs are now referred to in American slang as "junk", a word which hardly raises an eyebrow. And even the most dreaded of all - the "F" word - is no longer so mighty: Working-class English males use it as a glorified auxiliary verb in almost every sentence.
Dr Mohr believes that this cycle of new swear words replacing fading ones, a process which once took centuries, is now moving much faster due to the Internet. Chat rooms and social networking sites allow people to express themselves more freely and anonymously.
Swear words, therefore, predominate and are no longer so shocking.
There is also a broader intellectual climate which regards the use of swear words as "liberating". It is noticeable, for instance, that almost every review of this book published by an English-language newspaper went out of its way to print as many obscenities as possible, as though they were a badge of honour.
Still, every generation has its taboos, and ours may be racial slurs or derogatory references to personal disabilities. So, while a politician who utters the "F" word is no longer likely to suffer, if he calls people "niggers", "retards" or "cripples", his career would be over instantly. "Our sexual and excremental terms may one day be considered as mild as religious oaths are today, but it seems safe to say that epithets will remain strong obscenities," says Dr Mohr.
And she concludes with an intriguing thought: That, as people live longer, the end of life would no longer be seen as a natural process but as an "avoidable injustice". So, "may you die" could become the ultimate obscene expression.
The book will be available at Kinokuniya next month at $35.24 with GST.
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