Some people may be attracted to others over minimal similarities

"Our attraction to people who share our attributes is aided by the belief that those shared attributes are driven by something deep within us: one's essence," said lead author Charles Chu, PhD, an assistant professor at the Boston University Questrom School of Business. "To put it concretely, we like someone who agrees with us on a political issue, shares our music preferences, or simply laughs at the same thing as us not purely because of those similarities, but because those similarities suggest something more -- this person is, in essence, like me, and as such, they share my views of the world at large."

This thought process is driven by a type of psychological essentialism that is applied specifically to people's ideas about the self and individual identity, according to Chu, adding that people "essentialize" many things -- from biological categories such as animal species to social groups such as race and gender -- and do so in virtually all human cultures.

"To essentialize something is to define it by a set of deeply rooted and unchanging properties, or an essence," said Chu. "For example, the category of 'wolf' is defined by a wolf essence, residing in all wolves, from which stems attributes such as their pointy noses, sharp teeth and fluffy tails as well as their pack nature and aggressiveness. It is unchanging in that a wolf raised by sheep is still a wolf and will eventually develop wolf-like attributes."

Recently, researchers have begun to focus on the category of the self and have found that just as we essentialize other categories, we essentialize the self, according to Chu.

"To essentialize me is to define who I am by a set of entrenched and unchanging properties, and we all, especially in Western societies, do this to some extent. A self-essentialist then would believe that what others can see about us and the way we behave are caused by such an unchanging essence," he said.

To better understand how self-essentialism drives attraction between individuals, researchers conducted a series of four experiments. The research was published in the Journal of Personality and Social Psychology.

In one experiment, 954 participants were asked their position on one of five randomly assigned social issues (abortion, capital punishment, gun ownership, animal testing, or physician-assisted suicide). Half the participants then read about another individual who agreed with their position, while the other half read about an individual who disagreed with their position. All participants then completed a questionnaire on how much they believed they shared a general view of the world with the fictitious individual, their level of interpersonal attraction to that person and their overall beliefs in self-essentialism.

Researchers found that participants who scored high on self-essentialism were more likely to express an attraction to the fictitious individual who agreed with their position and to report a shared general perception of reality with that individual.

A similar experiment involving 464 participants found the same results for a shared attribute as simple as the participants' propensity to overestimate or underestimate a number of colored dots on a series of computer slides. In other words, the belief in an essential self led people to assume that just a single dimension of similarity was indicative of seeing the entire world in the same way, which led to more attraction.

In another experiment, 423 participants were shown eight pairs of paintings and asked which in each pair they preferred. Based on their responses, participants were identified as either a fan of the Swiss-German artist Paul Klee or the Russian painter Wassily Kandinsky. Half of each fan group was then told that artistic preference was part of their essence; the other half was told it had no connection. All were then exposed to two hypothetical individuals, one of whom had the same artistic preference and one who differed. Participants who were told that artistic preference was connected to their essence were significantly more likely to express an attraction to a hypothetical person with the same artistic preferences than those who were told artistic preference had nothing to do with their essence.

A final experiment categorized 449 participants as fans of one of the two artists and then presented them with information about whether using one's own essence was useful or not in perceiving other people. This time, one-third of the participants were told that essentialist thinking could lead to inaccurate impressions of others, one-third were told that essentialist thinking could lead to accurate impressions of others and the final third were given no information.

As expected, researchers found participants who were told that essentialist thinking could lead to accurate impressions of others were more likely to report attraction to and shared reality with hypothetical individuals with similar art preferences.

Chu said he was most surprised to find that something as minimal as a shared preference for an artist would lead people to perceive that another individual would see the world the same way as they do. Self-essentialist thinking, though, could be a mixed blessing, he warned.

"I think any time when we're making quick judgments or first impressions with very little information, we are likely to be affected by self-essentialist reasoning," said Chu. "People are so much more complex than we often give them credit for, and we should be wary of the unwarranted assumptions we make based on this type of thinking."