Couples psychologist, John Gottman, is something of a legend in the interpersonal psychology world. Gottman is famous for his ability to predict divorce with over 90% accuracy following his process of interviewing and observation. Here's Anderson Cooper, a US media figure, waxing lyrical on the subject.
But though his work is often noted for it's relationship to marriage break down, and the 'four horsemen' of the end of a relationship, he has spent just as much time on relationship stability. His work on stability he summarises neatly with his 'magic' rule for relational balance:
we need to balance each bad thing we do to our partner with five good ones on average
This little gem of wisdom stems from Gottman's 'couple typology', in which he describes the five major types of romantic couple. Gottman believes that by analysing these relationships, which vary wildly in behavioural traits, for this magic rule, we can tell which relationships are destined for success and which for failure.
Essentially, depending on whether the rule is in effect, couples are either 'regulated' or 'unregulated' (or 'non-regulated'). Regulated couples are those that regularly meet thier ratio. Unregulated couples don't and as such, are more dysfunctional than their counterpart. There are three couple types that are regulated, the other two are unregulated, and though they might look very different, they're united under the rule.
Volatiles are couples who are highly emotional. A rollercoaster if you will, with many ups and downs, but somehow throughout they manage to balance things out, overwhelming the downs with five times the ups. Volatiles are typically very passionate with lots of sex, arguing, love and happiness. But despite appearances of volatility, they are nonetheless regulated and so stable.
Validators show less emotion. These couples have a much more relaxed type of relationship, with a lot of talking through problems. They're extremely good at accommodating one another and also at meeting needs before they become an issue.
Conflict Minimizers are similar to validators, but where validators might fight, conflict minimizers don't think it's worth the trouble. When problems arise, they're more likely to let it go because the relationship is too valuable to argue. Instead, they'd much rather spend time focusing on the positives.
Hostiles are the most obviously dysfunctional. This relationship more resembles warfare than couplehood. Hostiles are sick of the relationship and sick of each other. There are lots of exit behaviours: actively attacking each other, blaming each other, and the worst of Gottman's four horsemen contempt.
Detached couples are also hostile, but less overt. This is more like guerrilla warfare. These couples will occasionally skirmish, but will detach completely in the intervening period. According to Gottman, this is the most common 'pre-divorce' pattern of behaviour. Vicious attacks followed by days or even weeks of neglect. And, this one is possibly the worst kind, because ignoring your partner when they need support is often particularly distressing.
The couples that are unregulated are far more likely to be divorced (or consider it) over a four year period than regulated types. This is the source of Gottman's predictive ability: he searches for the couples adherence to the rule and from that can predict whether they'll be divorced within four years.
Gottman's magic number is fun, but I would suggest it's not going to be a huge amount of help to us. We have neither the tools nor the experience available to Gottman's lab to score our relational behaviours. Instead, what we know now is that when we make mistakes, we have to compensate by being substantially more attentive and caring than we were before. It's not simply enough to apologise and move on. Not even if you're a 'conflict minimiser'. Five to one is a 500% difference, and an apology is not that.