As four-letter F-words go, fart is pretty tame. That in itself is remarkable, considering how closely related farting is to shitting. Surely life is full of phenomena both offensive and ephemeral for which fart (or a dysphemism thereof) would make an excellent metaphor, don’t you think?
Yet, although the Oxford English Dictionary claims that fart is “not now in decent use,” censoring fart is almost never necessary. Euphemisms for fart are outnumbered by those for shit manyfold, and one could even submit that the more colloquial ones—cut one, let one rip—are no more euphemisms than straightforward substitutions to add colour to speech or text. Insults involving fart are relatively few and innocuous, the most common being artsy fartsy and old fart, where the old is arguably more semantically important. Compare queef, which is quite an effective insult: “He said that? What a queef!”
What accounts for our tolerance for fart? Maybe it just doesn’t sound offensive enough. (It has a vaguely onomatopoeic ring, although the word has Indo-European origins that go way back.) Or maybe we can’t stay mad when we talk about farts because they’re hilarious.
In “Why Flatulence is Funny,” professor of philosophy James S. Spiegel offers an erudite ten-page analysis :
First, flatulence is humorous because it produces a sudden sense of superiority. As a social taboo, passing gas signifies a lack of self-control and, thus, diminished dignity. This perception of the other’s diminished dignity results in the psychological effect that Hobbes terms ‘sudden glory’. The effect is most pronounced when the person involved holds a position of public prestige or high standing, since the equalizing effect of their flatulence represents a more dramatic shift of perception….
Flatulence is also funny because of multiple incongruities it presents. One of these regards social context. Except for the bathroom, the socially designated area for excretory functions, flatulence is out of place. This is especially so at formal occasions such as weddings, academic lectures, or newscasts…. Flatulence also often contradicts the dignity of social standing….
Lastly, flatulence prompts laughter because, being socially taboo in most contexts, the phenomenon invites a release of nervous energy in the form of laughter among those who witness it. This nervous energy is attributable at least in part to the fact that we all share a similar fear – and perhaps some painful memories – of passing gas in a very public and therefore embarrassing way.
Having seen many a months-old baby laugh at his or her own farts, I can’t help wondering if it’s more fundamental: perhaps the combination of the sensation, sound, and smell simply makes farts inherently and universally funny.
While the hilarity of farts is unquestionable, their trustworthiness is another issue. “Never trust a fart” became a widely shared tidbit of wisdom after Jack Nicholson’s character uttered it in the 2007 film The Bucket List. Since then, others have co-opted it, warning about the dangers of trusting a fart while intoxicated or while recovering from stomach flu. Evolution helpfully equipped the human body with a sophisticated bundle of nerves that “provides constant sensory input from the rectum, helping us tell the difference between gas, liquid stool, and solid stool.” On rare occasions, though, those signals fail us, and the result is a literal and lexical blend of shit and fart—the dreaded shart.
The perceived harmlessness of fart in contrast to the vulgarity of shit makes the evolution and acceptability of shart interesting to follow. Shart has had an Urban Dictionary entry since 2003 but has seen more common use in the past handful of years. When Al Roker admitted in a 2013 interview to having pooped his pants at a White House event shortly after his gastric bypass surgery, online media were quick to label the incident a shart, and in 2014 Comedy Central ran its first Shart Week, its answer to the Discovery Channel’s Shark Week. It would seem that media reluctant to overtly use shit are not as shy about using shart. Because shart has such an obvious meaning and so succinctly fills a niche in our language, I’m inclined to believe it’s here to stay—although apparently it hasn’t yet gained enough momentum for the business behind shart.com to rebrand itself.
 James S. Spiegel. “Why Flatulence Is Funny,” Think 12 (35): 15–24. doi:10.1017/S1477175613000158.
 David Bub, Susannah L. Rose, and W. Douglas Wong. 100 Questions & Answers about Colorectal Cancer. Burlington, MA: Jones & Bartlett Learning, 2007.