No doubt you’ve heard the contradictory clichés regarding similarity and attraction: “Opposites attract” versus “Birds of a feather flock together.” Which is correct? Scientific evidence suggests that we are attracted to those we perceive as similar to ourselves (Miller et al., 2007). This is known as the birds-of-a-feather effect. One explanation for this phenomenon is that people we view as similar to us are less likely to provoke uncertainty. In first encounters, they seem easier to predict and explain than people we perceive as dissimilar (Berger & Calabrese, 1975). Thus, we feel more comfortable with them.

Similarity means more than physical attractiveness; it means sharing parallel personalities, values, and likes and dislikes (Markey & Markey, 2007). Having fundamentally different personalities or widely disparate values erodes attraction between partners in the long run. At the same time, differences in mere tastes and preferences have no long-term negative impact on relationship health, as long as you and your partner are similar in other, more important ways. For example, I like heavier music (Motörhead, Mastodon, Pantera), and my wife hates it. But we have very similar personalities and values, so our attraction and our relationship endure.

Because differences in tastes and preferences don’t predict relationship success, you shouldn’t dismiss potential romantic partners because of their minor likes and dislikes. Instead, first see whether you share similarities in personality and values.