The psychology of commitment and marriage

Last week I had the great honour of presenting at the Budapest Demographic Summit. The conference was a celebration of Hungary’s ‘family friendly’ policies

Last week I had the great honour of presenting at the Budapest Demographic Summit. The conference was a celebration of Hungary’s ‘family friendly’ policies that have seen their fertility rate rise from the lowest in Europe to above the EU average over eleven years and to see their marriage rate nearly double. The conference was headlined by Hungary’s President and former families minister Katalin Novak with talks from prime minister Viktor Orban, Italy’s prime minister Giorgia Meloni, the presidents of Bulgaria and Serbia, a dozen or so families ministers from around the world, and 60 other speakers including me.

(Incidentally, if you applaud Hungary’s family policies but are wary of Hungary’s reputation in the west, watch this fascinating interview with Viktor Orban and decide for yourself)

Here is a written version of my talk on the psychology of commitment and marriage:

“If you want to stick at doing something, you need two things.

You need to want to do it. In a relationship that means you want to be a couple with a future. You have chosen one another. You have rejected all the other choices. You have become an ‘us with a future’. And that’s crucial because clarity about the future allows forgiveness and sacrifice to prosper, vital characteristics of successful relationships. This is the inner bond of commitment that researchers call interpersonal commitment or dedication. We want to be together.

But there’s another aspect of commitment that goes with the grain of human nature and helps us stick at things when we don’t feel like it. It’s called constraints. You need to have to do it. Constraints are the bonds that make it harder for you to leave, should you wish to do do. They get us through the hard times. If we live together, it’s harder to leave than if we don’t live together. That’s a constraint. If we have children, it’s harder to leave than if we don’t have children. Being married and having the support of your friends are also constraints. They make it harder to leave. These are usually good things. They go with the grain of human nature because they help us stick together on those days when we are grumpy or don’t feel like it. We have to be together.

The timing of dedication and constraints is also important. These days, couples are quick to move in together which adds a constraint that makes it harder to leave. But if you haven’t established some sense of dedication before you move in together, a plan for the future, then fragile relationships can drift onwards and even lead to children before they eventually break up. This is perhaps the best explanation why cohabiting couples tend to be more likely to split up – not always but on average – because constraints preceded dedication. Without dedication, the constraints of living together or having children can feel like a trap.

Hardly anyone talks about the psychology of cohabitation. But nor do many talk about the psychology of marriage. It is deeply compelling. In the act of marriage, the ingredients of commitment – dedication and constraints – happen automatically and in the right order.

When we propose, we make a choice to reject other choices. We send a signal about our intent. That puts us both on the same page and removes any lingering doubt or ambiguity or even asymmetry of commitment. We all know where we stand. And when we act upon this decision, we increase the attractiveness of the choice we’ve made and decrease the attractiveness of the choices we’ve rejected. That happens automatically to maintain consistency and avoid cognitive dissonance between our thoughts, feelings and actions. The action of a proposal thus boosts the appeal of the choice we’ve made and makes us more confident that the decision is a good one. This all combines a whole bunch of psychological theories which are well established in other fields but we don’t often think about them applying to marriage.

Whereas the proposal is all about dedication, the wedding ceremony is about confirming our dedication and also adding an important constraint. To increase our chances of sticking together, we also need the backing of friends and family. One of the purposes of a wedding ceremony is to provide social affirmation that the risky choice we’ve made is a good one. But standing up and making a promise in front of so many people also makes us accountable. Doing that makes it harder to leave if we ever wanted to do so. And that’s a good thing of course. Marriage is the ultimate step of dedication precisely because we are prepared to announce it the people we most care about around us. So the wedding is about both dedication and constraint.

Having established that the psychology of marriage is so compelling, the paradox is why much of the research literature is so equivocal about saying marriage is clearly more stable than cohabiting. Yes, the raw fact is that married families as a whole generally have better outcomes. As couples, they are more likely to stay together and avoid poverty. And their children tend to have better educational and well-being outcomes. But the research also suggests much or even all of this apparent advantage comes not from marriage but from the kind of people who marry, who might be richer or older or better educated or happier.

But there is a serious omission in much of this research. As part of my PhD work at the University of Bristol I have replicated studies that have deeply influenced British government policy by claiming that marriage itself adds little benefit to family outcomes. I shall leave to one side the glaring hypocrisy that the vast majority of politicians and academics continue to embrace marriage in their private lives despite saying it doesn’t matter in their public policies.

Here’s the omission. When we look at other factors like age and education and income and happiness, the statistical models only include those people who have answered questions on every one of these background factors. Anyone who missed a couple of questions for whatever reason gets dropped from the analysis. This is called missing data. Although missing data tends to involve only a few questions for each person, all of this adds up.

So imagine you have 1,000 couples in your survey. I found that the research that has had the most influence on the British government in effect only considered the responses of 750 couples who answered all of the questions. And in this group, there is indeed little difference between married and unmarried couples. But I also found that the 250 couples who were dropped were disproportionately likely to be unmarried couples who also split up. Add these couples back in to the analysis using modern techniques and, bang, suddenly we find a huge gap between the married and unmarried couples, as predicted by the psychology theories. This important technical issue suggests that much recent research which omits missing data may be significantly understating the effect of marriage.

To conclude, whereas the ingredients of commitment are optional for couples who merely live together, they are baked in to the act of marriage automatically and in the right order. The psychology of marriage is thus deeply compelling.

As more researchers get to grips with the problem of missing data, I believe the next generation of research will show, like mine, that the effects of marriage have been dramatically understated. Marriage matters.”

Harry Benson, Budapest Demographic Summit, September 2023

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