Imagine yourself as one of your ancestors. Not a hundred or a thousand years ago, but one of your progenitors from some 100,000 years back in the mist of time.
You’ve fallen from a tree, tripped on a rock, stepped in a pile of dung, or barked your knuckles while sharpening a tool. Your natural response is to utter a sound of fury — an Ur-expletive — “arrgh!”
And for some reason, this lessens the pain. Swearing is natural because it has a hypoalgesic effect; it reduces the sense of agony. Indeed, swearing has always been attached to any experience of strong emotion, punctuating the profound.
Given this, you’d expect that we would have a record of such words in our culture stretching back to antiquity. But we don’t, because strong language has traditionally been a taboo and only in recent history has it been allowed in print.
Go back some 50 years, you’ll find Bowdlerization and grawlix to be ubiquitous. “G—–n!” and the like are normal in period literature. The editing set were forceful in suppressing expletives from print. When the Nixon tapes were released, [expletive deleted] was rampant throughout the transcription.
Our understanding of swearing as a linguistic speech act has to be inferred from hints and clues peppered throughout recorded history. We see it in ancient graffiti, in Latin words like “irrumo” (face-fucking), and in phrases like, “He swore like a sailor.”