Because, as Depeche Mode put it, “Things get damaged, things get broken…”. They do get damaged and broken, and changed, and challenged and different, and you do get scared, terrified and uneasy by the change, damage and brokenness. So no, you don’t swear because you’re rude, uncultured, mean, unfit for civilized conversation, are trying to be dangerous or bad ass… you swear because things go wrong and that causes fear that triggers a very old structure in the brain made to warn other of a dangerous thing, be it a predator approaching, dangerous location, the potential of fire to burn you…

If you’re not a potty mouth that has introduced swear words into your vocabulary as regular phrases just as you would say “uuummm” or “like”, in which case it moved from a place of an ancient mechanism for signaling danger to the place of something that has become a habit by constant repetition, you would swear only in unexpected extraordinary circumstances – you stub your toe, drop your phone, have to rapidly slam on the breaks because someone in front of you didn’t signal they would be turning, you grab a hot pan… Most of the times the words you swear with will be short and abrupt, an outburst of air that forms a monosyllabic loud sound and it is beyond your control. These old sounds are archaic and can be found in our ancestors as well. Monkey populations have a similar soundscape for signaling danger and warn others to hide, run, get onto the thin branches or move up into the trees where a predator can’t get them… You don’t use the same linguistic mechanism for regular structured speech as you do for swearing. When you’re speaking in full sentences your brain inhibits this old structure of signalization. This is also why people with Turrets syndrome swear. No matter how strange it seems that a disorder would cause a person to swear, the biological underpinning is that in people with Turrets the inhibitory system is compromised so they can’t control their reaction no more than you can control uttering something vile when you cut your finger. Longer bursts of swearing just mean that whatever you’re swearing about you see yourself as a victim of. You really might not be and it might not be dangerous at all but the mechanism is the same and the thing is labeled as a threat. It can be anything from not getting your way, being annoyed by something or someone, getting a bad grade or failing to do what you’re attempting to do.

So no you don’t swear because you’re rude, but out of danger, fear and perceived victimhood. The next time the neighbor’s dog is barking relentlessly in an obscure hour, instead of indulging in a swearing argument go outside and pet the creature. Swearing might be a fast emotional release but in reality of not really dangerous things it does nothing, some attention to the dog keeping you awake just might.