Incongruity theory is the idea that humor arises when something violates your normal expectations. You encounter a situation, statement, or image that doesn’t fit the pattern your brain predicted, and that mismatch triggers amusement. It’s the most widely accepted explanation of humor among philosophers and psychologists today, and it underpins most modern research into why we laugh.
The Core Idea
At its simplest, incongruity theory says humor happens when your brain detects a clash between what you expected and what you actually experience. A joke’s punchline works because it sends your thinking in a direction you didn’t see coming. A clown slipping on a banana peel is funny because people aren’t supposed to fall down like that. The surprise of the mismatch is what produces the feeling of amusement.
Consider a pun like “The magician got so mad he pulled his hare out.” Your brain processes two incompatible meanings simultaneously: one where the magician yanks out his own hair in frustration, and another where he performs a rabbit trick. That collision of meanings, packed into a single sentence, is incongruity in action.
The philosopher Søren Kierkegaard described the same phenomenon as a “contradiction” between what is expected and what is experienced. The writer William Hazlitt called it a “convulsive and involuntary movement, occasioned by mere surprise or contrast” that happens before the mind has time to reconcile what it’s seeing. Different thinkers have used different vocabulary, but the underlying mechanism is the same: your mental framework gets disrupted, and the result is laughter.
Where the Theory Came From
Incongruity theory has roots stretching back centuries, but it took its clearest shape in the 18th and 19th centuries through the work of several philosophers. James Beattie, Immanuel Kant, and Arthur Schopenhauer each developed versions of the idea that humor depends on some kind of mismatch or unexpected contrast. Kant, for instance, described laughter as arising from “the sudden transformation of a strained expectation into nothing.” Schopenhauer framed it as the disconnect between a concept and the real object it was supposed to represent.
These thinkers were reacting to an older explanation of humor, the superiority theory, which held that we laugh because we feel better than someone else. Incongruity theory shifted the focus away from social dynamics and toward the cognitive experience of the person laughing. It asked not “who are you laughing at?” but “what pattern did your brain just fail to predict?”
How It Compares to Other Humor Theories
There are three major theories of humor, and each one explains a different piece of the puzzle. Incongruity theory focuses on the stimulus: what makes something funny in the first place. Superiority theory focuses on the relationship between people, arguing that mockery, ridicule, and laughing at others’ foolishness are central to humor. Relief theory, associated with Sigmund Freud, focuses on the psychology of the listener, proposing that laughter releases pent-up emotional tension.
These three approaches don’t necessarily contradict each other. As humor researcher Victor Raskin has pointed out, they characterize humor from very different angles and actually supplement each other. Philosopher John Morreall offers a useful distinction: incongruity theory describes a cognitive change, relief theory describes an affective (emotional) change, and superiority theory involves both. You can think of incongruity as explaining the mechanics of a joke, superiority as explaining why teasing can be funny, and relief as explaining why you might burst out laughing during a tense moment.
Detection and Resolution: The Two-Stage Model
Modern psychologists, particularly Thomas Schultz and Jerry Suls in the 1970s, refined incongruity theory by arguing that detecting the mismatch isn’t enough. What people actually enjoy is resolving the incongruity, making sense of how the unexpected element fits after all. This became known as the incongruity-resolution model, and it describes humor comprehension as a two-step process.
First, you notice something doesn’t add up. The punchline contradicts the setup, or the image clashes with the caption. Your brain flags this as a semantic conflict. Second, your brain works to reinterpret the situation so it makes sense in a new, unexpected way. When you “get” a joke, that click of understanding is the resolution phase. If the incongruity can’t be resolved at all, the result is confusion rather than amusement. If there’s no incongruity in the first place, the result is boredom.
Brain imaging studies have mapped this two-stage process to specific neural activity. Incongruity detection activates regions involved in recognizing semantic conflicts and retrieving stored meaning. Resolution activates different regions responsible for integrating new interpretations and resolving ambiguity. Researchers have proposed a three-stage neural circuit for verbal humor: detecting the incongruity, resolving it, and then experiencing the feeling of amusement as a distinct third phase.
Where Incongruity Theory Falls Short
The biggest criticism of incongruity theory is that not all incongruity is funny. A car accident is unexpected. A disease diagnosis violates your expectations about your health. Neither is humorous. If incongruity alone explained humor, anything surprising would be amusing, and that’s clearly not the case.
Researchers have also pointed out that “incongruity” itself is poorly defined. The literature uses it to mean at least four different things: surprise, juxtaposition, atypicality, and violation. These are related but not identical concepts, and lumping them together makes the theory harder to test.
To address these gaps, psychologist Peter McGraw and colleagues proposed the benign violation theory. Their argument is that humor requires not just incongruity but a specific type: something that threatens your well-being, identity, or beliefs while simultaneously seeming okay. The “benign” part is crucial. A pie in a comedian’s face is a violation that feels safe, so it’s funny. A brick to someone’s head is a violation that feels genuinely harmful, so it’s not. In six studies using entertainment, consumer products, and social interactions as stimuli, the benign violation framework predicted what people found funny more accurately than standard incongruity measures, particularly by weeding out situations that were joyful, amazing, or tragic but not actually humorous.
Incongruity in Language and Wordplay
Linguist Victor Raskin formalized the role of incongruity in verbal humor through his Semantic Script Theory of Humor. Under this framework, a text is funny when it activates two “scripts,” essentially two incompatible interpretations, at the same time. The magician/hare pun is a clean example: one script involves anger and hair-pulling, the other involves stage magic and rabbits. The humor lives in the overlap where both scripts are plausible.
Computational researchers have tried to quantify this. By measuring the “ambiguity” of a sentence (how strongly it supports two different meanings) and the “distinctiveness” of those meanings (how different they are from each other), they’ve built models that roughly correspond to incongruity and resolution. Higher ambiguity means more incongruity. Greater distinctiveness means a more satisfying resolution. The funniest puns tend to score high on both.
How Incongruity Humor Develops in Children
Babies don’t start with an appreciation for wordplay. The developmental timeline of humor begins with social smiling around 5 to 9 weeks, followed by laughter in response to physical stimulation at about 3 months. By 5 months, babies laugh at social games like peekaboo. Between 7 and 9 months, visual incongruity starts getting reactions: a parent wearing a bowl as a hat, for example.
By around 9 to 11 months, infants begin creating their own humor, and by 10 months, many engage in deliberate “clowning,” producing absurd events on purpose to get a reaction. Most 6-month-olds already laugh at absurd nonverbal behavior from their parents. Researchers have noted that laughter at incongruity serves a cognitive purpose beyond entertainment. It keeps the infant oriented toward the unexpected event, maximizing their opportunity to understand it. In other words, the humor response may have evolved partly as a learning tool, rewarding the brain for engaging with things that don’t fit the pattern.
Incongruity and Artificial Intelligence
One of the more revealing tests of incongruity theory comes from watching AI systems try to handle humor. Large language models can generate setup-and-punchline jokes using templates, and some perform reasonably well with straightforward formats. But research from 2024 and 2025 shows consistent struggles with the kinds of incongruity that humans navigate easily.
Models have particular difficulty with puns that rely on similar-sounding words (rather than words with double meanings), because they lack genuine phonetic knowledge. Longer jokes built on sustained incongruity and humor that depends on niche cultural references present even greater challenges. When AI models misinterpret an early reference in a topical joke, the error cascades through their reasoning process, compounding into a completely wrong explanation. Studies asking models to explain “nonsense with depth,” humor that uses sarcasm, irony, or tautology alongside absurdity, find that they struggle significantly to produce high-quality explanations. The gap highlights just how much incongruity processing depends on flexible, context-sensitive thinking that current AI architectures haven’t fully replicated.