Why do humans laugh? Philosophy, ethics, and the social meaning of humour

By Barry Newman

Barry is a retired intensive care consultant. He leads the school visiting team at Dorset Humanists and has spoken to thousands of students about humanism in schools across the Bournemouth area.

In this edited transcript of a recent talk for Dorset Humanists, he explores one of the most familiar yet elusive features of human life. Drawing on medicine, philosophy and cultural history, he asks why we laugh, what humour does for us socially, and where its ethical boundaries lie.

Let me begin with a disclaimer. I’m not a stand-up comedian. A comedy set is not my natural habitat, and if you came expecting slick delivery and killer punchlines, you may feel short-changed. What I can offer instead is a talk about humour – though I hope, here and there, it will also contain some humour. That turns out to be a surprisingly tricky thing to do. Humour is one of those deeply familiar human experiences that becomes more mysterious the moment you try to pin it down. We all know when something is funny — but we are often at a loss to explain why.

From bodily fluids to bad jokes

The word humour comes from the Latin humor, meaning bodily fluid. Ancient physicians believed that human wellbeing depended on a balance between four humours: blood, phlegm, black bile and yellow bile. An excess or deficiency in one of these supposedly produced particular personality traits: sanguine (upbeat, optimistic), phlegmatic (calm, chilled), melancholic (reflective, low), or choleric (quick-tempered, passionate). Early humour, in this sense, involved laughing at people whose personalities were unbalanced or eccentric.

By the sixteenth century, humour had come to mean poking fun at distinctive or exaggerated traits. Comic actors mimicked eccentrics; audiences laughed at those who deviated from a perceived norm. From the outset, then, humour had an ambiguous moral status. It could delight, but it could also humiliate.

So what is humour? Dictionaries tell us it is communication that causes amusement or makes us laugh — but that merely kicks the problem down the road. What is amusement? Why do we laugh? And why do we laugh at some things and not others?

Humour is not laughter

One thing that helps is to separate humour from laughter. They are related, but they are not the same thing. Laughter is overwhelmingly a social phenomenon. We are apparently around thirty times more likely to laugh when we are with other people than when we are alone. Laughing alone is, frankly, rather odd. Most everyday laughter has nothing to do with jokes at all. It functions as social glue: signalling agreement, empathy, reassurance, friendliness, or the easing of awkwardness.

We laugh nervously. We laugh politely. We laugh to soften disagreement. We laugh to show we belong. There is also laughter contagion — fits of the giggles that erupt between people who share a strong bond, often triggered by nothing in particular. Anyone who has experienced this knows how powerful and inexplicable it can be.

Because my background is in medicine, I can’t resist mentioning pathological laughter — uncontrollable laughter associated with certain brain injuries or rare forms of epilepsy. I once knew a medical student who, for nearly two years after a head injury, giggled in utterly inappropriate situations. It was socially agonising, and it brought home just how context-sensitive laughter is. In the wrong place, at the wrong time, it becomes deeply disturbing.

All of this suggests that laughter is a form of social communication, not simply a response to humour.

The ancients were not amused

Humour itself has had a rocky reception in the history of ideas. The ancient Greek philosophers — Plato, Aristotle, and the Stoics — took a dim view of it. Reason was their highest value, and humour was seen as undermining rational control. Plato worried that comedy encouraged vice by ridiculing respectable figures and delighting in undignified behaviour. Aristotle was little more enthusiastic and

Christian thinkers were scarcely more relaxed. Augustine warned that laughter distracted from spiritual seriousness. A thousand years later, Aquinas conceded – with great restraint – that appropriate laughter might be healthy if it served recreation and harmed no one. It took Christianity a remarkably long time to lighten up, and even then only slightly.

Superiority: laughing at

The first systematic theory of humour is the superiority theory, articulated most clearly by Thomas Hobbes. Laughter, he argued, arises from a sudden feeling of glory when we compare ourselves favourably to others. We laugh because we feel superior.

It is easy to recognise this kind of humour. It belittles through ignorance, error or naivety. Modern comedians call it ‘punching down’. It can boost the self-esteem of the laugher, but it does so at someone else’s expense.

Superiority humour can be softened – gentle teasing rather than cruelty – and it often becomes acceptable when the joke is told from within the group being mocked. A Jewish joke told by a Jew, or racial humour told by someone reclaiming their own identity, changes the moral dynamic. We are laughing with, not at.

Still, superiority theory fails as a general explanation. It cannot account for wordplay, absurdity, self-deprecation, or the rich seam of humour mined by comedians who laugh at the strangeness of everyday life rather than at other people.

I have sometimes wondered whether superiority humour reflects pre-Enlightenment societies, where individual dignity was not strongly valued and hierarchical mockery was normal. The Enlightenment, by affirming the worth of each person, may also have reshaped what we find funny – or acceptable.

Incongruity: expectation subverted

The strongest contender for a general theory of humour is incongruity theory. Humour, on this view, arises when there is a mismatch between what we expect and what actually occurs – a subversion of expectation. Puns rely on this. So do plot twists, anti-climaxes, and absurd situations. Even babies seem to laugh at incongruity: peekaboo, surprise faces, sudden appearances and disappearances.

There is something deeply human about delighting in the unexpected.

Philosophers have refined this idea in various ways. Kant thought humour came from the sudden collapse of mental tension – an expectation built up and then abruptly released. Schopenhauer saw humour as momentary liberation from the suffering imposed by a blind, irrational world. Freud regarded humour as a mature defence mechanism, allowing us to confront painful realities while maintaining emotional distance.

All of these capture something real. Humour can defuse tension, provide perspective, and make the unbearable manageable. But incongruity theory also has limits. Not all unexpected things are funny. Some are grotesque, horrifying, or simply puzzling. Surrealist art and bizarre architecture may be deeply incongruous, but they rarely make us laugh. Incongruity can evoke wonder, curiosity or problem-solving rather than mirth. One philosopher has sensibly suggested that incongruity becomes funny only when it is non-threatening. That strikes me as important.

After all this theorising, I am left with a slightly uncomfortable conclusion: I still don’t fully understand why some things are funny and others are not. All the theories are partial.

One intriguing observation is that artificial intelligence is very bad at humour. Ask it for a joke and you tend to get something technically structured but emotionally flat – often a pun you have heard before. If that is the best machines can do, it suggests that humour involves something more than pattern recognition.

Despite claims that animals have humour because they play, I remain unconvinced. Animal play looks more like training – coordination, speed social bonding – than comedy. Humour seems to be a peculiarly human way of navigating meaning, surprise, vulnerability and shared understanding.

Humour and culture

Humour is also profoundly cultural. Western humour often relies on satire, irony, sarcasm, exaggeration and self-deprecation. British humour prides itself on understatement; American humour often favours boldness and explicitness.

East Asian humour offers a striking contrast. In China and Japan, humour tends to be subtler, more polite, and more group-oriented. Wordplay is common, supported by languages rich in homonyms (words that sound or look alike e.g. the word ‘bank’ has more than one meaning). Humour that humiliates or undermines social standing is far less acceptable.

Traditional Chinese xiangsheng (‘cross-talk’) comedy involves dialogue rather than solo performance, with mild slapstick and little overt humiliation. Japanese manzai similarly relies on quick-fire exchanges between a straight man and a funny man, delivered deadpan. Both traditions focus on human interaction rather than set-piece jokes. There is also modern Chinese ‘Sang’ humour — ironic defeatism expressed through memes and advertising slogans like ‘New day, new sadness’. It may not be our kind of humour, but it clearly speaks to a shared emotional landscape. Across cultures, humour reflects what a society permits, values and fears.

Ethics: laughing with, not at

This brings us to the ethics of humour. The key question is always: who is the target? Punching up — mocking power, authority, pretension — can function as social critique. Punching down — ridiculing the marginalised or powerless — reinforces harm. Locker-room humour may feel bonding in private, but it can perpetuate misogyny and violence. Intention matters. Context matters. Laughing with is almost always better than laughing at. Humour is a social tool, and like all tools it can heal or wound depending on how it is used.

Humanists owe much to philosophy, so let me end with a philosophical joke.

An angel appears at a college faculty meeting and offers the head of the philosophy department one of three gifts: wisdom, beauty, or ten million dollars. The professor immediately chooses wisdom. There is a flash of light, and he sits in silence, transformed. A colleague whispers, “Say something.” The professor lifts his head and says, “I should have taken the money.”

Humour, like philosophy, reminds us of our limits. It punctures pretension, releases tension, and – at its best – connects us. Perhaps that is why, for all our theories, humour remains stubbornly resistant to explanation. And maybe that is exactly the point.