John and Julie Gottman are renowned clinical psychologists and researchers who've dedicated decades to finding out why some marriages last and others sour.
The two have interviewed more than 3,000 couples and followed some for as long as 20 years. They have also studied more than 40,000 couples who are about to begin couples therapy.
In their recently released book "The Love Prescription: 7 Days to More Intimacy, Connection, and Joy" they synthesize years-worth of data into a plan that can heal a teetering relationship or help maintain a thriving one.
"What we've discovered is that there are universal factors that make or break a relationship, that predict whether a couple will stay together happily, or not," they write.
During one of their biggest longitudinal studies, they discovered that there is one math equation which "makes you or breaks you" in a marriage: The ratio of positive to negative interactions during a conflict needs to be five to one.
"We watched couples, logged the data, then released them back into the wild," they write. "Six years later we followed up. And lo and behold: it was the couples who had maintained at least a five-to-one ratio (or more!) during conflict who were still happily together, still feeling the love."
Much of the couple's research is conducted through the Gottman Love Lab, a research center at the University of Washington that John co-founded in the 1980s.
For this study, the Gottmans asked couples to come into the lab and try to resolve a disagreement in 15 minutes. They recorded the conflict, watched the tapes and categorized each interaction as positive or negative.
A smile, touching the other person's hand, saying "I understand" — all positive. Making a nasty remark, blaming, or acting disinterested are classified as negative.
When they checked back in with the couples six years later, those whose ratio of positive to negative interactions were at least five to one were much better off.
Why such a stark imbalance? Why can't making a little joke cancel out raising your voice? To put it simply, negativity is more impactful.
"Negativity has much more power to inflict damage and cause pain than positivity does to heal and bring you closer," they write.
They also found that intention did not matter. Even if your intention is positive, yelling at your partner is a negative interaction.
"The difference between the extremely unhappy couples and very happy couples boiled down to one simple thing: the happy couples were kinder when they spoke to each other," they write. "They treated each other more gently, without criticism, contempt, or sarcasm."
Outside of arguments, this ratio jumps even higher, they found. During everyday life you need at least 20 positive interactions for every negative one. This is the ratio "masters of love" maintained.
To create so much positivity you must admire your partner, they write, and express that admiration to them. If you love the way they recount their day to you or how much they value their morning routine, tell them.
"Don't let those thoughts and feelings pass without sharing them with your partner," they write. "Grab on to them; hand them to your partner like a tiny gift. It's a gift for you, too."
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