Swearing is fucking great. I mean, some people don’t think so, and that’s fine, but you can’t deny swearing has power. No really, you can’t, science fucking says so. Studies show that your pain management greatly improves when you swear. It’s purely psychological of course, you can’t just substitute the swear word with an angry noise and get the same effect. So, when you hit your thumb with a hammer, you call the hammer a cunt, and then throw it through a cunting window and then scream at your bastard wife when she asks you what the cunt you think you’re playing at.
Swearing has power, and that’s why it’s a useful tool for the writer. The right swear word at that right time can amplify a threat, lend further weight to despair, or sharpen the edge of spite. And that’s not even getting into the comedic potential, where a swear word can act like a punch line in and of itself (if you ever need to end a scene on a high note, have a sweet old lady say “piss flaps”.)
This is not to say, however, that a writer shouldn’t exercise restraint. Not for any kind of moral reason, but to increase the impact. Just like violence, sex and humorous ethnic comic relief, too much of a good thing can lessen its value. Saving your big guns for the right moment can give you some vital muscle when its needed, which might otherwise be lost in the static of a dropping an f-bomb every paragraph.
Of course, that’s no iron clad rule. Casual swearing can be hilarious, or it can set the entire tone of your piece. Think about any Tarantino movie, for example, or anything by Irvin Welsh. Your book may want to reflect a type of social environment where everything is expressed through enthusiastic genital references. That’s fine and perfectly valid.
You may, however, want to write a book where no on uses any foul language at all. It’s perfectly possible, I’ve done it myself (if you don’t count crap, bugger, arse and hog-shagger which… I guess are swear words, actually, now that I think about it.) But you will be depriving yourself of some of the most creative, historic and powerful words known to the English tongue. These words have weight and history, and no, I don’t mean internet puffery like “twat waffle” and “cum burglar”, I mean the classics. Stuff that goes right back to Chaucer. You shouldn’t be ashamed of them, or to admit they have power. Break ‘em out like a surgeon breaks out the bone saw now and then.