The whole concept of 'swearwords', IMHO is terribly outdated anyway. As someone else mentioned above, while these select words are considered taboo, their synonyms are not. Why is it okay to say 'crap' or 'poo' and not 'shit'? They mean the exact same thing. I can only imagine it was taboo to say 'shit' in public because of what it meant, but no-one seems to care about that any more. Everyone remembers it's a taboo word, but not why.