Cursing is cool. It just is. Ask anyone.

In his new book What the F: What Swearing Reveals About Our Language, Our Brains, and Ourselves (UK) Benjamin Bergen—a linguist in the Cognitive Science Department at UC San Diego—tries to explain exactly why cussing is so amazing. His self-described “book-length love letter to profanity” defines what makes a swearword and why using one feels so great. Although What the F has its share of silliness, it’s full of cute tidbits you can drop at cocktail parties, like how all Samoan babies’ first words are “eat s#!t” and how Japanese completely lacks curse words. Japanese people with Tourette’s syndrome blurt out insults and childlike words for genitalia that are generally considered impolite and inappropriate, but not profane.

Across unrelated languages—Bergen mentions Cantonese, Russian, Finnish, American and British Sign Languages, Hebrew, Arabic, Italian, German, and Quebecois French in addition to English—curses largely fall into four categories. There are words that deal with prayer, the divine, and the supernatural (the word “profane,” after all, is the counterpoint to the word “sacred”). There are also words that deal with sex, various sex acts, the people who perform them, and the body parts involved. Other words cover the act of excreting, as well as the excretions themselves.

Finally, there are slurs, which are the only swears that have been demonstrated to cause harm to those who use and hear them. The others, despite the protestations of the FCC and generations of conservative parents, have not been found to have ill effects on anyone.

Curse words are different from the rest of language, as evidenced by how they seem to be exempt from regular rules of grammar and instead can engender their own. But the most interesting aspect of their distinction is that they are processed in the brain differently from regular speech.

What we learn from brain damage

Many brain regions have been found to be responsible for particular functions when they are damaged and their functions are impaired—Phineas Gage’s accidental frontal lobotomy revealed that his severed frontal lobes regulated impulse control and social behavior. Bergen’s favorite model patient suffered from aphasia, or language impairment due to brain damage. This patient was a priest who had a stroke in 1843, after which he could not speak. But oh boy could he curse.

Studies from people with different types of aphasia have delineated different brain regions that regulate different aspects of communication. Wernicke’s area is like a dictionary: it helps us to understand the meanings of the words we hear and to choose the words we want to use in a particular context. People with damage to this area can’t understand language, yet they can pronounce words and assemble sentences—it’s just that the sentences they come up with don’t make any sense. Broca’s area is in charge of producing sounds; people with damage to this area have trouble articulating words and sentences.

But both Wernicke’s aphasics and Broca’s aphasics, and even global aphasics, can swear. These swear words are coming from somewhere else in the brain, not the parts known to be responsible for generating the rest of language.

These foul-mouthed aphasics can only produce their curses in a reflexive, spontaneous manner, not intentionally. This is a type of automatic speech—think of what comes out of your mouth when you stub your toe or forget that your Pyrex pan just came out of the oven so you pick it up with both hands. Automatic speech seems to originate in structures in the right hemisphere of the brain, whereas Wernicke’s and Broca’s areas are on the left.

This information came from another aphasic patient, the converse of the cursing priest, who lost his ability to swear. He sustained damage to his basal ganglia, which is involved in motor control and emotional responses—it's also damaged in people with Tourette’s. Bergen thus suggests that profanity, which we know expresses strong and often fleeting raw emotional states, originates not in the parts of our brains that regulate rational speech, but in the more ancient neural pathways that regulate impulse and emotion.

While that seems like a substantial bit of information, this pop neuroscience takes up all of one chapter. The rest of What the F deals with how bad words came to be and how they impact individuals and society. It’s a quick read, not a detailed, academic dissection. But don’t mistake breeziness for triviality: cursing plays a central role in our lives.

Slurs hurt

Since slurs are curses, they can come out without thought, in a moment of primal, unfiltered emotion—such as a coach or athlete might experience when he feels a ref made an egregiously wrong call. Despite this lack of thought, slurs can hurt. People are more likely to discriminate against a group of people when they hear that group maligned, and members of the maligned group can be adversely affected as well.

Even so, Bergen does not think it wise to punish people for using slurs, as the NBA and NFL have done, or to ban or at least moderate their use, as the FCC tries to do. Rather, he advises that people who are tempted to use slurs be kinder and more respectful; conversely, those who hear them should relax and not always get so worked up. Legislation has not really worked to temper any kind of hate speech, so it is nice—although it seems naive—to think that Bergen’s common-sense approach could work. Given that Bergen works on a university campus, perhaps he can use this strategy to try to generate a “safe space” for everyone, regardless of their vocabulary.