Opposites attract, or at least that’s what movies like When Harry Met Sally and Pretty Woman tell us. Outside of Hollywood, however, can people with dissimilar personalities really grow together over the course of a relationship? In a paper published in the journal Personality and Individual Differences, researchers concluded that spouses’ personalities do not in fact change over time.
As we grow older, we become more set in our ways. Indeed, adult personalities are known to be less flexible than those of children. Therefore, researchers for this project were interested in whether personalities could be changed by a significant “environmental” factor: a spouse. Previous studies have shown that newlyweds tend to have a greater number of shared personality traits with their spouses in comparison to other people chosen at random. Still, this finding doesn’t solve whether spouses become more like each other over time or they selected one another because of preexisting similarities.
To answer this question, the researchers administered an extensive personality questionnaire to 1,300 married couples whose marriages had lasted anywhere from two to 39 years. The test assessed 10 basic aspects of personality, including health, social tendencies, achievement, social closeness, stress reaction, aggression, alienation, control, harm avoidance, and traditionalism. The researchers analyzed the questionnaire results to see if the couples from longer marriages were more similar to each other than couples that hadn’t been married as long.
As it turns out, the couples that were married for a brief amount of time had just as many personality similarities as those who had been married for decades. Of all the personality traits examined, aggression was the only one where couples became more similar over time. Why aggression? The researchers figure that spouses feed off each other’s hostility, thus becoming more aggressive over time.
Let this study be a lesson in compatibility. Evidently, most spousal similarities are present at the time of marriage, meaning that many people select mates who are similar to themselves from the start, be it consciously or unconsciously.