The internet loves a particular kind of story: the one where your most irritating habit turns out to be a secret marker of genius. Messy desk? Sign of a brilliant mind. Stay up late? Higher IQ. Swear like a sailor? Actually a sophisticate. Most of this is comforting nonsense, the psychological equivalent of a horoscope that only ever flatters you. But not all of it. A couple of these annoying habits genuinely do have research behind them, linked not to intelligence in the grand sense but to specific, measurable cognitive skills. The honest exercise is sorting the real from the wishful, and being clear about how much even the real findings actually prove.
Swearing, and the vocabulary myth
Start with the best-evidenced one, because it overturns a widespread assumption. The common belief is that people who swear a lot do so because they lack the vocabulary to express themselves better. The research says close to the opposite. In a study by Kristin and Timothy Jay, participants were asked to generate as many curse words as they could in a set time, and their performance was compared with standard tests of verbal fluency. The people who could rattle off the most taboo words also tended to score highest on general verbal fluency, which led the researchers to conclude that a rich vocabulary of swear words goes along with a rich vocabulary overall, rather than signaling a poor one.
They summarized it as fluency is fluency. Producing a lot of curse words on demand draws on the same verbal facility as producing a lot of animals or a lot of words starting with a given letter. So the person with the colorful mouth is, if anything, demonstrating command of language rather than a shortage of it. The swearing may still be annoying. It is just not evidence of a small vocabulary, and may quietly indicate the reverse.
Doodling, and the wandering mind
The second habit with real support is doodling, the scribbling in the margins that looks like the very picture of not paying attention. Here too the research flips the assumption. In a well-known experiment by the psychologist Jackie Andrade, people listened to a dull, rambling phone message while half of them were given a simple doodling task and half were not. The doodlers recalled about 29 percent more of the information afterward than the non-doodlers, suggesting that far from being a sign of a drifting mind, doodling can actually help a person stay focused during a boring task.
The likely explanation is that a monotonous task leaves the mind with spare capacity that tends to wander off into full daydreaming, which wrecks attention. A small, undemanding doodle soaks up just enough of that spare capacity to keep the person anchored to the room without distracting them. So the colleague sketching in the margin of the meeting agenda may be listening more closely than the one staring politely into space, not less.
The habits that do not hold up
Now the honest correction, because most of the genre is far thinner than these two. The famous claim that a messy desk signals a superior mind rests largely on a single small study that found messy environments encouraged more creative choices, which is a narrow finding about creativity in a moment, not a verdict on anyone’s intelligence, and it has not held up as any general law. The idea that night owls are smarter comes from weak, much-disputed correlations that barely survive scrutiny. Talking to yourself, procrastinating, being chronically late: each has its viral study, and each is far shakier than its confident headline suggests.
The pattern is that a genuinely interesting small result gets stretched into a sweeping claim it never supported. It is worth being suspicious of any article promising that your particular flaw is secretly a gift, because that is exactly the story people most want to hear, and the demand for it far outstrips the evidence.
The caveat that applies to all of it
Even the two findings that do hold up need handling with care, and the same cautions apply across the whole genre. These are correlations, not proof that the habit causes or reveals anything; swearing and verbal fluency travel together, but that does not make one the source of the other. They come from individual studies, some quite small, and single studies are a starting point, not settled fact. And crucially, they link a habit to a specific narrow ability, verbal fluency, sustained attention, not to general intelligence or IQ, which is a much broader thing that no single quirk could capture.
So even at their best, these findings say something modest: that a particular habit tends to accompany a particular skill, on average, with exceptions everywhere. They emphatically do not license reading someone’s intelligence off their habits, in either direction. The quiet, tidy, non-swearing person is not thereby less clever, and the doodling one is not thereby a genius.
Where it leaves us
The appeal of this whole genre is obvious. It takes something we have been mildly criticized for and hands it back as a hidden strength, which feels wonderful. The honest version is less flattering but more interesting. A couple of supposedly annoying habits, fluent swearing and idle doodling, really are backed by decent research linking them to genuine cognitive skills, and that is a pleasing thing to know. Most of the rest is wishful thinking dressed as science. And none of it, not even the real findings, should be used to size up how smart anyone is, including yourself. The most intelligent response to any annoying-habit-equals-genius headline is a small, well-placed dose of doubt, which is a habit worth having whatever it signals.