Why do happy couples argue more?

And what has Bayes' theorem got to do with it?

Grant and Hepburn proving that arguments are sexy in Bringing Up Baby. (More examples from the movies here.)

I’m sad to announce that last week’s longish piece went down well which means this week’s is even longer (skip to the Miscellany if this appalls you).

In last week’s Ruffian I talked about Thomas Bayes’ theorem and how it informs my thinking. Once you know a little about Bayesianism you start seeing applications of it everywhere, which is what happened to me as I was writing about the science of relationships for CONFLICTED.

In the first part of the book, I look at evidence for the immense benefits of conflict and argument; at home, at work and in society generally. In one chapter I look at some fascinating research on couples and conflict. The question of how and why couples argue is interesting in itself, but also because it offers a microcosm of all human relations. Here as elsewhere, we tend to underrate the power of arguments to bring people closer together.

Counsellors and advice columnists put a great emphasis on the avoidance of heated arguments. We are told to be patient, kind and compassionate to our partner, even when they annoy the hell out of us. Couples should communicate clearly and calmly about any matters of contention, rather than seek angry confrontation. Where there is discord, let us talk it out.

It all sounds terribly reasonable, doesn’t it? And terribly unrealistic. Many of the couples I admire most are unafraid of exchanging hot words on a fairly frequent basis. A row doesn’t have to represent some crisis in the relationship and a passion for combat can reflect a passion for each other. Anyway, in any intimate relationship worth the name, getting annoyed and frustrated with the other is part of the deal. Couples who never argue may live peacefully, but it’s hard to believe they are living honestly.

It’s taken a while for psychologists to recognise being endlessly reasonable is not necessarily the route to a healthy relationship. In the post-war years, when the modern science of romantic relationships was established, researchers discovered, unsurprisingly, that unhappy couples had a lot of heated rows. An orthodoxy was born: a happy couple is one in which partners share their feelings calmly and avoid hostile arguments. But while you can have too much of something, you can also have too little of it. There is now a growing body of evidence that conflict, including heated rows, makes relationships stronger.

You might be wondering how they measure this kind of thing. The basic methodology is that they invite couples to the lab, and ask them to discuss a source of tension in the relationship, on camera, without anyone else in the room. The couples soon forget they’re in an artificial situation. Some discuss the problem reasonably and coolly, others became hotly emotional. The researchers code and score everything that happens in these exchanges, from tone of voice to body language to blood pressure. They then monitor the couples over the months and years to come, checking in on how they’re doing. Then they look for patterns in the data.

Somewhat counter-intuitively, it turns out that more confrontational couples tend to be happier and more satisfied in the relationship than the always-amicable ones. For instance, John Gottman, one of the giants of the field, found that couples who are relatively quick to rise to provocation are more likely to stay together. Nickola Overall, a professor at University of Auckland who specialises in marital conflict, found that couples who argue readily make more headway in solving their differences.

“Conflict provides us with information,” she told me when I spoke to her for CONFLICTED. In argument, you learn about what the other really thinks and really feels. It is often only when your partner loses her temper that you understand how important it is to her or him that you do your share of parenting duties, or that you cut down on drinking. It also conveys emotional investment: sometimes it’s only in an argument that you find out how much the other cares about you. A row can act like a spotlight, illuminating each other’s internal world.

Of course, a marriage in which every conversation leads to a quarrel is awful for all concerned. And not every argument reveals something to work on. Sometimes what you learn, said Overall, is that you need to walk away. But the point is that conflict is not some unfortunate accident to be avoided at all costs; it’s how you find out the truth, about your partner, about yourself, about the relationship.

If you’ve been married for many years, you may feel you already know the truth, thank you very much, and that there is almost nothing worth upsetting the apple cart for. But be careful. Another intriguing finding is that the longer a couple stays together the less good they become at understanding each other. When tested on how well they can ‘read the mind’ of their partner, couples who have been together for decades perform less well than those who have been together a year or two.

This is where Bayesianism comes in (at least, it came into my mind when I was writing this chapter in CONFLICTED, though in the end I didn’t mention it). Bayes didn’t just come up with a theorem; he put his finger on something fundamental about how human beings perceive the world. As discussed last week, his essential insight is that when we’re presented with new and incomplete information, we needn’t work out what it means from scratch. Instead, we can make informed guesses about its significance based on our prior models of how the world works.

Many neuroscientists believe this is how our brains work. Locked inside its bone casing, the brain relies on messengers from the outside world to tell it what’s going on. Given limited and unreliable information from the senses, it has to build a detailed picture of the body’s environment in order to work out what to do next. To succeed, it makes informed guesses about what’s out there, building on the mental models it has developed from experience (what AI researchers call its training data) - models of how water pours, or of what a particular room looks like, or a face. In fact, a lot of what we feel as if we’re seeing and hearing directly is a mental simulation which sensory data merely updates and refines (optical illusions are a way of exposing the gap between what the eye sees and the brain expects). Crucially, using templates like this saves on energy. The brain is like a brutal cost-cutting manager in this regard, always looking for efficiencies.

Attention costs energy. The more reliable your prior mental model of a phenomenon, the less you attention you need to pay to it as it happens. Walk into someone else’s house and you expend a lot of cognitive energy taking in the surroundings. Enter your own house and you barely notice them, unless someone has changed the wallpaper without telling you. In other words, there has to be a big, unmissable discrepancy between the real world and your model of it for your brain to stump up some attention.

This takes us back to relationships. In the early months and years of a relationship, we are avid for information about the other’s mind and pay close attention to them. We start to build mental models of the other, updating as we go. After a while, you have built a pretty good model. You start to feel you can read the other’s mind. You know when your partner says she’s looking forward to something she’s really not looking forward to it, or that if she’s grumpy today it’s because she didn’t eat breakfast. In conversation, you can sometimes finish her sentences. It’s actually remarkable how fluent we can become at predicting another’s behaviour and thoughts (not just in the context of couples, of course - and in fact you apply all of this to close relationships generally).

But precisely because we develop this magic power, we get complacent. As the brain spots a way to conserve energy, we stop updating the mental model we have of our partner. Love might be a fixed mark but your beloved is changeable; while people tend not to undergo radical shifts in personality as they age, they are altered by experiences. Over time there can emerge a gap between the partner that exists in your head and the real person. The template becomes a mere stereotype. If that discrepancy grows too wide or continues for too long, it can end in a shocking rupture – your partner turns around and tells you they’re leaving.

When a stubborn gap like this exists, "talking it out” - discussing differences calmly and rationally - can actually make things worse. Since the model is skewed, we interpret everything that comes through it differently to our partner. We make mistakes of interpretation, seeing intentions where none exist or neglecting emotions that do. The more the couple talks, the more those inaccuracies show themselves, in a spiral of mutual incomprehension.

This is why arguments, which are as much about unspoken intuitions as they are about words, matter so much. Frequently and freely engaged in, they’re a spontaneous source of updates on how your partner is feeling, and what they are thinking. Confrontations blow away the cobwebs. The heat of a row melts the mask of politeness that we wear even with our intimates, revealing new truths, allowing you to see each other afresh. Conflict, even or especially what the British call a right old barney, forces us to pay attention to each other. It resets the model.


Please remember the word about The Ruffian. Email your friends. Shout about it on your socials. Berate your neighbours. It’s free but it does cost time and energy to produce, so think of this as your fee. Use this link. Oh and of course, please do buy my book for more on the role of argument and disagreement in human relationships - and on how to do conflict well.

How to buy CONFLICTED - here are links to your favourite booksellers (UK and US).


  • Reminder that if we’re looking to blame technology for the polarisation of American politics, TV is at least as much to blame as the internet.

  • This is a gripping example of Bayes’s theorem being used to solve a real world problem.

  • No, Britain is not an economy built on zero-hours contracts and temp jobs.

  • Belgian study of seatbelt wearing: men are much less likely to wear one when accompanied by another man. Another study finds that poor people are much less likely to wear a rear seatbelt than rich people. (Via Rob Henderson, who studies the psychology of social status).

  • Adam Buxton’s conversation Kazuo Ishiguro is really special, highly recommended. Recently I happened to re-watch The Remains of the Day, the great Merchant-Ivory adaptation of Ishiguro’s novel. Buxton and Ishiguro discuss a deleted scene from the movie, the excision of which is apparently controversial and hotly disputed, not least by the people who made the movie. It was meant for the end of the story, and it shows Stevens, the butler, played by Anthony Hopkins, breaking into tears. You can watch it here. It is an incredible, moving scene, exquisitely played, perfectly shot. But Merchant and Ivory cut it because they felt it didn’t fit the emotional landscape of the movie. Whether they got that decision right to or not (Ishiguro isn’t sure they did) it’s a supreme example of ruthless creative self-discipline. Here you have made this beautiful thing, but if it doesn’t fit the internal logic of the work, it must go!

  • Last year I enjoyed Haruki Murakami’s book on running (as much about the practice of writing and self-improvement as it is about running). I’ve just finished his book on classical music, Absolutely On Music, actually a co-production with the great Japanese conductor Seiji Ozawa. It consists of Murakami chatting to Ozawa about the latter’s life and craft, over a series of afternoons. Murakami can’t read music but he’s deeply knowledgeable about it. He’s also decidedly unpretentious, as is Ozawa. So you get a fine education in the details of making great music, presented in a relaxed, accessible way. It’s a unique combination. I loved it, it has made me listen more and better. One day I’ll get round to reading a Murakami novel.

    CONFLICTED is available everywhere you need it to be - seize the moment.