Part of what defines a friendship is what that friendship is founded on. For people to be friends, something has to connect them, but the nature of that connection is different from one friendship to the next.
In many cases, part of the foundation of a friendship is similarities – in terms of personality traits, experiences, hobbies or attitudes, for example.
Some psychology research has suggested that there might be something to the adage about birds of a feather flocking together. In particular, it may be that certain types of similarities may strengthen friendships and contribute to those friendships’ positive effects.
For example, one way friends can be similar is in terms of personality. A recent study published in Frontiers in Psychology found that friend groups led to a greater sense of identification and bonding when members were more similar in terms of the personality traits neuroticism and conscientiousness.
Interestingly, that wasn’t just true for individuals who were more similar to the group. Individuals in the group also experienced those advantages when other people in the group were more similar to each other, regardless of how similar those people were to the individual.
Those advantages might make a real difference in people’s lives. A 2018 study found that premedical students were more likely to stay on their career paths when they had friends with more similar life experiences.
By interviewing the premed students, the authors of that study found several concrete behaviors that seemed to give an advantage to students with more similar friends, including receiving emotional support from their friends and guidance from peers further along in their studies.
Similarity among friends might show up in the way people respond to social media, too. A 2019 study of teenagers’ Instagram usage found that having more similar Instagram friends facilitated a type of “benign envy” that made teens feel more inspired.
Of course, it’s worth acknowledging that seeking out people with different perspectives and backgrounds probably has its own set of advantages that aren’t captured in these studies. At the same time, though, forming friendships based on similar personality traits or life experiences does seem to offer several benefits, including in group bonding and receiving emotional support.