Q: My friend thinks I’d do better in dating if I went on sites that match people according to “similarities.” Most of the couples I know aren’t that similar. Could those sites be wrong? How much does similarity matter for being a good match with somebody and the chances of a relationship working out long term?—Single Woman
A: Some points of difference are simply a bridge too far—like if one partner enjoys hunting dinner and the other weeps every time an egg is fried.
However, there are three areas in which partner harmony seems essential to happy coupledom. If couples have clashing religious beliefs, political orientations or values, “it’s found to cause tremendous problems in a marriage,” explained psychologist David Buss at a recent evolutionary psychology conference.
Beyond the big three—shared religion, political orientation, and values—the notion that you and your partner need to “match” to be happy together isn’t supported by science. In fact, science finds otherwise.
The notion that partners should match like a pair of nightstands has powerful intuitive appeal, leading many people—including psychologists—to buy into the notion we’ll be happiest if we find somebody just like us. Dating sites take advantage of this widely believed myth, hawking features like the “billion points of similarity” compatibility test.
Dating sites advertising themselves with a meaningless test might not seem like a big deal. But it reinforces the myth that partner similarity equals romantic happiness, and this belief has a downside, according to research by psychologist Michael I. Norton and his colleagues.
Consider when we first meet a person, we get excited about our apparent similarities: “You like sticking up banks! I like sticking up banks!” At this point, and in the early days of a relationship, we’re prone to identify similarities where none exist, spinning ambiguities—vague or missing details about a person—into support for their being just like us. But Norton explains that as partners get to know each other, dissimilarities begin to surface. And this leads partners who were initially stoked about how alike they seemed to be to become less satisfied with each other and the relationship.
Interestingly, dissimilarity between partners gets an undeserved bad rap. Discovering this took more sophisticated methodology than used in previous research. Psychologist Manon van Scheppingen and her colleagues instead explored interactions between romantic partners’ personality traits over an eight-year period. Their findings suggest partners don’t have to match perfectly on traits; and sometimes having differences is ideal.
Take conscientiousness, a personality trait reflecting self-control and a sense of responsibility to others. According to the research, if one partner was low in conscientiousness, their relationship worked better and they were happier when they were with somebody higher in conscientiousness. Likewise, relationships worked better when partners had varying levels of extraversion.
The upshot is that happy coupledom depends on an interplay of factors. This in turn suggests that what makes for happy relationships is largely “process”—how two people communicate, foster each other’s growth, solve problems and manage the intractable ones.
Beyond this and the three vital areas where partners need to be in tune—religion, politics and values—what’s important is for partners to not be sharply different in ways that will make them unhappy together. To avoid that, you need to dig into yourself and figure out what your deal breakers are. For example, if you’re an urban girl like me, no amount of love would change your belief that there’s only one reason to spend a month in a cabin in the wilderness without indoor plumbing, and it’s because you’ve been kidnapped and are tied to a chair.
