You only need five minutes alone with a couple to tell if they're going to last. That's what psychologist John Gottman found in 1986, when he gathered a bunch of newlywed couples in a "Love Lab" and observed them interacting with each other. Six years later, he had predicted with 94 percent accuracy who would stay together and who would break up [via Business Insider].
It turns out that couples who stay together are (1) kind to and (2) generous with each other. Wow! While in the Love Lab, Gottman was measuring the couples' physiological responses after prompting them to ask each other simple questions about their respective days. The couples who snipped at each other (and hence had higher heart rates and sweated more) were broken up by the time Gottman saw them next. Contrastingly, the ones who were nice to each other and asked questions were not physiologically aroused at all and they were the ones who passed the six-year mark.
Really, it's that simple. He explains: "The problem was that the [failed group] showed all the signs of arousal—of being in fight-or-flight mode—in their relationships. Having a conversation sitting next to their spouse was, to their bodies, like facing off with a saber-toothed tiger...It's not that the [successful group] had, by default, a better physiological make-up than the disasters; it's that [they] had created a climate of trust and intimacy that made both of them more emotionally and thus physically comfortable."
This article originally appeared on Cosmopolitan.com. Minor edits have been made by the Cosmo.ph editors.