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ARTICLE
Why people make friends: The nature of
friendship
Menelaos Apostolou | Despoina Keramari | Antonios Kagialis |
Mark Sullman
Department of Social Sciences, University
of Nicosia, Nicosia, Cyprus
Correspondence
Menelaos Apostolou, Department of
Social Sciences, University of Nicosia,
46 Makedonitissas Ave., 1700 Nicosia,
Cyprus.
Email: m.apostolou@gmail.com
Abstract
Friendship constitutes an important facet of human
behavior, and the current research investigated the rea-
sons that motivate people to make friends. First, a com-
bination of qualitative research methods were used to
identify 41 perceived reasons why people make friends.
Using a sample of 1,316 Greek-speaking participants,
these reasons were classified into five broad factors.
Participants indicated that the most important reasons
for making friends were to receive social input, sup-
port, and because of someone else's good qualities. Sex
differences and age effects were found in most factors.
Finally, the five factors were classified into two broader
domains, the first reflecting motivation to make a true
friendship and the second to gain opportunistic
benefits.
KEYWORDS
evolution of friendship, friendship, making friends, reasons for
making friends
1|INTRODUCTION
Friendship can be defined as a long-term relationship of mutual affection and support
(Fehr, 1996; Hruschka, 2010). Making friends constitutes an important facet of human behavior
and is found across all contemporary and historical human societies (Demir, 2015; Desai &
Killick, 2010; Terrell, 2014). This human universal raises the question of why people make fri-
ends, which the current research aims to address.
Received: 4 June 2020 Revised: 6 October 2020 Accepted: 15 October 2020
DOI: 10.1111/pere.12352
© 2020 International Association for Relationship Research
Pers Relationship. 2020;1–15. wileyonlinelibrary.com/journal/pere 1
The ethologist Nikolaas Tinbergen proposed four major categories for explaining an organ-
ism's behavior, namely, adaptive value, phylogeny, mechanism, and ontogeny (Tinbergen, 1963).
Adaptive value refers to how a behavior contributes to an animal's survival and reproductive suc-
cess, which can also be called fitness. Phylogeny refers to how a behavior has evolved, that is,
how evolutionary selection pressures modified an organism's behavior over time. Adaptive value
and phylogeny constitute “ultimate”explanations of behavior; that is, they examine the fitness
consequences of the behavior (Scott-Phillips, Dickins, & West, 2011). Mechanism refers to the
physiology of behavior, which is the mechanism that gives rise to a specific behavior, and ontog-
eny refers to how behavior develops over an organism's lifetime. Mechanism and ontogeny consti-
tute “proximate”explanations; that is, they are concerned with the mechanism(s) that underpins
a behavior—how it works (Scott-Phillips et al., 2011). Overall, ultimate explanations address the
evolutionary function of the behavior (the “why”question), and proximate explanations address
the way in which that functionality is achieved (the “how”question) (Scott-Phillips et al., 2011).
The current article attempts to address both ultimate and proximate causes of friendship. In par-
ticular, we initially attempt to identify the adaptive value of friendship, that is, the fitness benefits
that individual derive from making friends. Subsequently, we attempt to identify the proximate
causes, that is, the actual reasons that lead people to make friends.
1.1 |The evolution of friendship
Humans have spent most of their evolutionary time in a preindustrial context, living as hunters
and gatherers (Lee & Devore, 1968). In such a context, people relied heavily on others for their
own and their families' survival. For instance, men would form parties to hunt large game (Lee &
Devore, 1968), whereas women would rely on each other's help for raising their children
(Hrdy, 2009). Consequently, having people around with whom one can cooperate effectively
could considerably increase one's chances of survival. Furthermore, in this context, there were no
social protection systems, and people had to rely on others if misfortune found them. Thus, hav-
ing someone who would provide assistance in a time of need could be the difference between life
and death. For instance, hunters who were injured and were unable to hunt could receive meat
from a fellow hunter who was in good health, and they could return the favor at a future time.
Mutual help and effective cooperation would have also been beneficial in the later stages of
human evolution (about 10,000 years ago to the 18th century and the onset of the industrial rev-
olution), where our ancestors based their subsistence on cultivating the land and on herding
animals (Bocquet-Appel, 2011). Although these societies were more technologically advanced
and produced more wealth than hunting and gathering ones, they still lacked social support
systems, meaning that people had to rely on the assistance of others in times of need. People
also had to cooperate effectively with each other to gain their subsistence. For instance, cultivat-
ing a large plot of land would require the effective cooperation of several individuals. Overall,
surviving in an ancestral environment required good cooperation and assistance from other
individuals, which in turn favored behavioral mechanisms that enabled people to establish con-
nections or friendships with others who could cooperate effectively toward common goals and
be relied upon in times of need (Hruschka, 2010; Kruger, 2003; Tooby & Cosmides, 1996). On
this basis, we argue that one motivational factor for individuals to make friends would be to
have others with whom they can work effectively and receive support in times of need.
Humans are social animals that have evolved to live in groups (Aronson, 1980). Group living has
evolved because it has several advantages, such as protection from external threats (Ward &
2APOSTOLOU ET AL.
Webster, 2016). For example, ancestral foragers could better defend themselves from wild animals in
groups rather than on their own. To put it differently, people wandering alone in the African savan-
nahwouldprobablyhaveendedupasfoodforwildbeasts. In addition, as discussed above, group liv-
ing gives the opportunity to people to cooperate toward gaining their subsistence. For instance, it
would be difficult for individuals to hunt large game on their own, something made much easier in
cooperation with others (Packer & Ruttan, 1988). Accordingly, in the ancestral preindustrial context,
not being surrounded by other people could considerably compromise an individual's chances of sur-
vival. Therefore, selection forces would favor the evolution of mechanisms that prevent people from
becoming socially isolated. For instance, lonelinessisonesuchmechanism:Itgeneratestheunpleas-
ant feeling of loneliness when individuals do not receive social contact, which encourages them to
seek the company of others to overcome this feeling (Apostolou, 2016; Cacioppo, Cacioppo, &
Boomsma, 2014; Cacioppo, Cacioppo, Capitanio, & Cole, 2015, see also Tooby & Cosmides, 2008).
These mechanisms would motivate people to establish connections or friendships with others so that
they do not experience negative emotions. On this basis, we predict that another motivational factor
for making friends is to have reliable sources of social input.
The arguments above indicate that people have evolved mechanisms that motivate them to
establish friendships with other people. These mechanisms could, however, be exploited for
achieving goals other than friendship. One such goal is mating. More specifically, in the disguise
of friendship, individuals may approach someone who they are interested in having as a mate
rather than a friend (A. L. Bleske-Rechek & Buss, 2001). That is, people may use friendship as a
first step, planning to change the relationship into something more intimate later. They may also
use this strategy to approach a prospective friend's friend or relative who interests them. On this
basis, we can predict that one motivational factor for making friends is for mating purposes.
Furthermore, friendship involves mutual help and support. Thus, in the disguise of friend-
ship, people may target specific individuals who they believe could help them achieve personal
goals of advancement. For instance, people may attempt to become friends with their bosses to
receive better treatment at work. Another possibility is that they may approach high-status indi-
viduals to augment their own status. On this basis, we predict that one motivational factor for
making friends is to achieve personal goals of advancement.
Overall, in our proposed theoretical framework, we identified four motivational reasons for
making friends, which are: to have a supportive network, to have people to socialize with, for mat-
ing purposes, and to achieve personal goals of advancement. The former two purposes are aimed
specifically at establishing a friendship, whereas the latter two aim to build friendships for other
ultimate goals. On this basis, we can predict that the four motivational factors would cluster in
two broader domains that would reflect this distinction. There has been considerable research on
interpersonal attraction and the development of relationships (Fehr, 1996; Lewis, Al-Shawaf, Rus-
sell, & Buss, 2015). There is also some work, in the child and adolescent literature, on the functions
of friendships (Mendelson & Aboud, 1999). However, to the best of our knowledge, there has not
been any research that has investigated the reasons people make friends and that classified these
reasons into broader factors and domains. This is the purpose of the current study.
1.2 |Sex and age effects
Ithasbeenproposedthatmenandwomendifferintheirmotivesformakingfriends.Morespecifi-
cally, it has been proposed that, because women are usually physically weaker than men, they have
historically been vulnerable to harm from human and nonhuman predators. Accordingly, women
APOSTOLOU ET AL.3
are more likely to make friends, especially those of the opposite sex, to have people around them
who are willing and able to support and protect them (Ellis, 1992; Mesnick, 1997; Ryder, Maltby,
Rai, Jones, & Flowe, 2016; Snyder et al., 2011; M. Wilson & Mesnick, 1997). Furthermore, A. L.
Bleske-Rechek and Buss (2001) have argued that people are also likely to make friends to have the
opportunity for casual sex. This strategy is more likely to be adopted by men, whose reproductive
success is predicted by the number of partners they have access to (see also A. Bleske-Rechek
et al., 2012; A. Bleske-Rechek, Joseph, Williquette, & Donovan, 2016). On this basis, we predict that
there would be sex differences in the perceived reasons for making friends, with women being more
likely to indicate that they would make friends to have people around to protect them and men
beingmorelikelytoindicatethattheywould make friends to achieve mating goals.
Furthermore, people's motives for making friends are likely to change with age. For
instance, younger individuals have less experience and fewer resources available, such as
money, for dealing with life's challenges, so they need more support than older individuals,
who are more self-sufficient. On this basis, it is predicted that younger individuals would be
more likely to indicate that they make friends to receive support than older individuals. Overall,
the current study aims to identify the perceived reasons for making friends, as well as sex and
age differences in these reasons.
2|STUDY 1
This study aimed to identify the perceived reasons that motivate people to make friends.
2.1 |Methods
2.1.1 |Participants
The study was designed and conducted at a private university in the Republic of Cyprus. Partici-
pants were recruited by advertising the study on social media outlets, such as Facebook. The
only condition for taking part was to be 18 years old or older. Participants did not receive any
monetary or other reward. For in-depth interviews, we employed a sample of 20 Greek-
speaking participants (10 women and 10 men) who had a mean age of 37.1 (SD = 5.4) years.
For the open-ended survey, we employed a sample of 108 participants (61 women and 47 men)
of a mean age of 23.7 (SD = 6.6) years.
2.1.2 |Materials
In-depth interviews
To identify the different perceived reasons that motivated people to create friendships, a series
of semistructured interviews was conducted. The interviews took place in a psychology labora-
tory located on the University premises and lasted 35 min on average. The interviews were con-
ducted by one of the authors and one independent graduate student. Participants signed a
consent form and then reported their demographic details (i.e., sex, age). The study received
approval from the University of Nicosia's Department of Social Sciences Ethics Committee. The
data were collected in March and April 2019.
4APOSTOLOU ET AL.
Participants were asked to discuss the different reasons that motivated them to make fri-
ends. For instance, people were asked: “Tell us some of the reasons that led you to establish
your current friendships.”We employed follow-up and probing questions to obtain more
detailed information on specific reasons. For instance: “You said someone's desirable character-
istics, could you give us some examples of these characteristics?”Participants' responses were
recorded on paper. Following the conclusion of the interview, participants were debriefed and
thanked.
Open-ended survey
The open-ended survey had two parts. In the first part, participants were asked the following:
“Please indicate as many reasons as you could think that have led you in the past or could lead
you in the future to make friends.”In the second part, demographic information was collected
(i.e., sex, age).
2.2 |Results
To analyze the data from the in-depth interviews and the open-ended questionnaires, we employed
a procedure used in previous research (Apostolou & Keramari, 2020). More specifically, two inde-
pendent graduate students were employed, a man and a woman, who coded and categorized
responses to superordinate categories. Similar responses were added to a superordinate category,
and when a dissimilar response arose, a new superordinate category was created. Answers that
contained multiple reasons were eliminated as they were difficult to interpret. Moreover, reasons
with unclear or vague wording were also eliminated. After processing about 30% of the responses,
the data for each coder were compared. The coders agreed on most of the superordinate categories.
However, in a few cases, there was not complete overlap, and one of the authors was consulted
before 100% agreement was reached on the superordinate categories. Subsequently, coders
proceeded to code the remaining responses. For these codes, Cronbach's kappa was 0.78.
Overall, we identified 41 perceived reasons, including “To have someone to support me,”
“To approach someone who interests me romantically,”“Someone's positive characteristics,”
and “The need for socialization.”The full set of reasons can be seen in Table 1. From Table 1,
we can also see that the most frequent reason was “the common interests with someone”
followed by the “so that I do not feel lonely”and “someone's character.”
3|STUDY 2
This study aimed to classify the reasons identified in Study 1 into broad categories of perceived
reasons motivating people to make friends and to assess their importance.
3.1 |Methods
3.1.1 |Participants
The study was designed and conducted in a private university in the Republic of Cyprus. The
study received approval from the University of Nicosia's Department of Social Sciences Ethics
APOSTOLOU ET AL.5
TABLE 1 The means and standard deviations for making friends as reported in Study 1. It also depicts the
extracted factors for making friends and the respective factor loadings in Study 2
Factors
Eigen
value
Factor
loadings Frequencies
Support 26.99
To have someone to support me (M= 3.38, SD = 1.16,
range = 4)
0.735 9
To have someone to discuss my problems with (M= 3.66,
SD = 1.14, range = 4)
0.727 7
To have someone to rely on in a time of need (M= 3.42,
SD = 1.21, range = 4)
0.717 7
To have someone to advise me (M= 3.39, SD = 1.14, range = 4) 0.714 3
To have someone to help me (M= 2.98, SD = 1.19, range = 4) 0.708 6
For mutual support (M= 4.02, SD = 1.04, range = 4) 0.577 9
To have someone to share my joys and my sorrows (M= 4.17,
SD = 1.02, range = 4)
0.575 6
The need to have someone to talk to (M= 3.79, SD = 1.10,
range = 4)
0.513 8
For support when I am in a new environment (M= 3.24,
SD = 1.17, range = 4)
0.445 6
To have someone to go out with (M= 3.31, SD = 1.23,
range = 4)
0.392 5
To have someone to do things together (M= 4.15, SD = 0.93,
range = 4)
0.350 6
Mating 12.67
To approach one of his/her relatives who interests me
romantically (M= 1.61, SD = 0.96, range = 4)
0.890 1
To approach one of his/her friends who interests me
romantically (M= 1.80, SD = 1.06, range = 4)
0.882 3
To approach someone who interests me romantically (M= 2.17,
SD = 1.23, range = 4)
0.805 3
To expand my social circle so that I have more chances to find a
partner (M= 2.07, SD = 1.17, range = 4)
0.754 4
I need someone to be with me when I go out looking for a
partner (M= 1.79, SD = 1.04, range = 4)
0.689 2
To approach others from his/her social circle that would be
useful to me (M= 1.87, SD = 1.06, range = 4)
0.652 2
Someone's appearance (M= 1.94, SD = 1.06, range = 4) 0.554 3
To raise my social status (M= 1.87, SD = 1.07, range = 4) 0.489 1
To have someone to admire me (M= 1.93, SD = 1.11,
range = 4)
0.481 2
Desirable traits 6.25
Someone's character (M= 4.54, SD = 0.71, range = 4) 0.707 20
Good chemistry with someone (M= 4.45, SD = 0.77, range = 4) 0.685 13
6APOSTOLOU ET AL.
Committee. The data were collected in September and October 2019. Participants were rec-
ruited by advertising the study on social media, such as Facebook and Instagram, and by
forwarding a link to the study by email to students, colleagues, and friends, asking them to for-
ward it further. The target group was Greek-speaking participants residing in Greece and in the
Republic of Cyprus. To take part, participants had to be at least 18 years old. No monetary
reward or other reimbursement was given for participation. Overall, 1,316 Greek-speaking indi-
viduals took part (676 women, 640 men). The mean age of women was 24.9 (SD = 12.1) years,
and the mean age of men was 28.6 (SD = 9.9) years.
TABLE 1 (Continued)
Factors
Eigen
value
Factor
loadings Frequencies
Someone's ethos (M= 4.24, SD = 0.94, range = 4) 0.671 4
Someone's positive characteristics (M= 4.22, SD = 0.88,
range = 4)
0.653 14
The common interests with someone (M= 4.19, SD = 0.84,
range = 4)
0.638 36
Someone's humor (M= 4.15, SD = 0.91, range = 4) 0.636 14
When someone appears to be trustworthy (M= 4.42, SD = 0.76,
range = 4)
0.590 4
My admiration for someone (M= 3.39, SD = 1.21, range = 4) 0.557 6
To share my interests (M= 3.95, SD = 0.96, range = 4) 0.461 11
If someone has opinions that I strongly agree with (M= 3.59,
SD = 1.04, range = 4)
0.452 5
Socializing 4.25
The need for contact with other people (M= 3.96, SD = 1.03,
range = 4)
−0.826 7
The need for socialization (M= 3.85, SD = 1.09, range = 4) −0.800 11
The need for communication (M= 4.21, SD = 0.90, range = 4) −0.688 9
The need for companionship (M= 3.86, SD = 1.06, range = 4) −0.632 11
The willingness to meet new people (M= 3.96, SD = 1.03,
range = 4)
−0.624 5
So that I do not feel lonely (M= 3.43, SD = 1.26, range = 4) −0.562 24
To expand my social circle (M= 3.07, SD = 1.25, range = 4) −0.525 3
The need for acceptance (M= 3.03, SD = 1.26, range = 4) −0.463 3
Career 2.97
In the work environment for best cooperation (M= 3.25,
SD = 1.12, range = 4)
−0.634 8
This friendship can be helpful in the future (M= 3.05,
SD = 1.32, range = 4)
−0.524 3
To help me advance my career (M= 2.30, SD = 1.09, range = 4) −0.489 2
APOSTOLOU ET AL.7
3.1.2 |Materials
The study was designed using Google forms, was in Greek, and appeared online. The survey
had two parts. In the first part, participants were asked to rate how likely each of the 41 reasons
identified in Study 1 was to motivate them to make friends. Participants' scores were recorded
on a 5-point Likert scale: 1—strongly disagree, 5—strongly agree. In the second part, demo-
graphic information (i.e., sex and age) was recorded.
3.1.3 |Statistical analysis
To classify the reasons for making friends into broad factors, a principal components analysis
with the direct oblimin rotation was used. Similarly, to classify the factors for making friends
into broader domains, principal components analysis with the direct oblimin rotation was used.
Furthermore, to identify sex and age effects, we ran a series of Multivariate Analysis of Variance
(MANOVAs), with the individual reasons comprising each factor being entered as dependent
variables. For instance, to estimate sex and age effects on the “Career”factor, we entered partic-
ipants' scores on the three reasons that comprise it. Moreover, participants' sex was entered as a
categorical independent variable, and participants' age was entered as a continuous indepen-
dent variable. This procedure was repeated for each extracted factor.
4|RESULTS
Starting from principal components analysis, the Kaiser-Meyer-Olkin (KMO) statistic was .95,
indicating that our sample was appropriate for factor extraction. Using the Kaiser criterion
(eigenvalue > 1), five factors were extracted. The internal consistency scores ranged from 0.63
to 0.90, with an overall consistency of 0.82. There were some reasons that loaded to more than
one factor. In particular, “the need to have someone to talk to”and “to have someone to go out
with”loaded also to the “Socializing”factor (−0.432 and −0.329, respectively). In addition, “to
raise my social status”and “to expand my social circle”loaded also to the “Career”factor
(−0.355 and −0.422, respectively). We classified these reasons to the factors for which they had
the highest loading.
The first factor to emerge was labeled “Support,”where participants indicated that they
would make friends to have people support them, to rely on in times of need, and to discuss
their problems and also to get useful advice. The second factor to emerge was labeled “Mating,”
where participants indicated that they would make friendships to approach someone who inter-
ested them romantically. Furthermore, they indicated that they would make friends with people
to approach their friends' friends or relatives who interested them romantically. They would
also make friends to have “wingmen”when they were out looking for mates and to broaden
their social circle so as to have higher chances of meeting prospective mates.
In the “Desirable traits”factor, participants would make friends if someone had good quali-
ties such as being trustworthy and having a good character, ethos, and sense of humor. In the
“Socializing”factor, people indicated that they would make friends to come in contact, social-
ize, and communicate with other people and to avoid feeling lonely. Finally, in the “Career”
factor, participants indicated that they would make friends to have better cooperation in their
8APOSTOLOU ET AL.
work environment and to help them in their careers but also because a friendship could be
proven useful in the future.
To examine which factors were more important in driving people to make friends, we calcu-
lated the means by summing the reasons that comprised each one and dividing them by the
number of items. From Table 2, we can see that the most important factor was “Desirable
traits,”followed by the “Socializing”factor. In the middle of the hierarchy was the “Support”
factor and at the bottom were the “Career”and “Mating”factors.
Moving on to the MANOVA analysis, the results are presented in Table 2, which shows that
there was a significant main effect of sex for all factors. As indicated by the effect size, the larg-
est sex difference was for the “Support”factor, where women gave higher scores than men. The
only exception was for the item “to have someone to go out with,”where men gave significantly
higher scores (M= 3.36, SD = 1.23) than women (M= 3.29, SD = 1.21). The second largest dif-
ference was for the “Mating”factor, where men gave higher scores than women. Finally,
women gave significantly higher scores than men in the “Desirable traits”and in “Socializing”
factors, whereas men gave significantly higher scores in the “Career”factor.
Significant main effects of age were found for all factors, with the exception of the “Mating”
factor, where the effect approached, but did not reach, statistical significance. As indicated by
the effect size, the largest effect was for the “Support”trait, where younger participants gave
higher scores. The second largest effect was for the “Desirable traits”factor, where older partici-
pants gave higher scores. Finally, small age effects were found for the “Socializing”and the
“Career”factors, where younger participants gave higher scores.
4.1 |Second-order factor structure
With respect to second-order principal components analysis, the KMO statistic was .72, indicat-
ing that our data were appropriate for factor extraction. Using the Kaiser criterion
(eigenvalue > 1), two domains were extracted (Table 3). The internal consistency of the first
domain was 0.77 and of the second was 0.70.
The first domain to emerge was the “True friendship,”which included the “Desirable
traits,”“Support,”and “Socializing”factors. The second domain to emerge was the “Opportu-
nistic friendship,”which included the “Mating”and the “Career”factors. To assess the relative
importance of each domain, we calculated the mean for each one and found that the “True
TABLE 2 Mean scores, sex, and age effects in Study 2
Factors Overall Women Men Sex Age
Mean (SD) Mean (SD) Mean (SD)p-Value η
p2
p-Value η
p2
Desirable traits 4.11 (0.56) 4.18 (0.54) 4.04 (0.58) <.001 0.043 <.001 (+) 0.036
Socializing 3.62 (0.81) 3.69 (0.75) 3.57 (0.82) <.001 0.038 .038 (−) 0.013
Support 3.59 (0.78) 3.68 (0.79) 3.48 (0.81) <.001 0.070 <.001 (−) 0.063
Career 2.86 (0.90) 2.82 (0.86) 2.91 (0.94) <.001 0.014 .012 (−) 0.009
Mating 2.84 (1.17) 2.59 (1.00) 3.10 (1.28) <.001 0.067 .087 (+) 0.012
Note: The signs in parenthesis indicate the direction of the relationship.
APOSTOLOU ET AL.9
friendship”domain had a higher mean (M= 3.78, SD = 0.60) than the “Opportunistic friend-
ship”domain (M= 2.85, SD = 0.92).
Finally, we investigated the degree to which each domain contributed to participants' moti-
vation to make friends. For this purpose, we calculated the percentage of participants who gave
a mean score above “3”(the middle of the scale) in both domains. We found that the percentage
was 36.6, which means that more than one in three indicated that both domains motivated
them to make friends.
5|DISCUSSION
In the current research, we identified 41 perceived reasons that motivate people to make fri-
ends, and we classified them into five broad factors. Participants indicated that the most impor-
tant ones were to receive social input, support, and someone's good qualities. Meeting an
intimate partner and to gain career benefits were considered to be less important reasons for
making friends. Sex differences were found in all factors. More specifically, someone's desirable
traits, socializing, and support were rated more highly among women than among men. In con-
trast, mating and career advancement were rated more highly by men as reasons motivating
them to make friends. Age effects were found for several factors. For instance, younger partici-
pants indicated a stronger motivation to make friends to have people to support them. A
second-order principal components analysis was used to classify the five factors in two broader
domains, one reflecting motivation to make a true friendship from which to derive support and
social input and the other to derive opportunistic benefits.
Our findings are consistent with the predictions of the proposed theoretical framework.
More specifically, as it was originally predicted, one motivational factor for making friends was
to have people around to provide support and assistance, especially in times of need. Similarly,
consistent with our original prediction, another motivational factor was to have people around
to receive social input. Participants were also interested in making friends with someone who
had good qualities, such as good character, and with whom they had things in common. One
interpretation of this factor is that people want to have others around to support them and to
provide social input, but this is unlikely to happen if prospective friends do not have good char-
acter traits or are not compatible with them. For example, if friends are selfish and unkind, it is
unlikely they will be there for them in a time of need. Similarly, if friends are incompatible with
someone, it is difficult to maintain a friendship from which adequate social input could be
received. Accordingly, if people find individuals with desirable traits, such as a good character
TABLE 3 The extracted domains in
Study 2
Domains Factor loadings
True friendship
Desirable traits 0.896
Support 0.747
Socializing 0.705
Opportunistic friendship
Mating 0.907
Career 0.791
10 APOSTOLOU ET AL.
and compatibility, they would be motivated to make friends with them because they would be
individuals from who they could derive support and social input.
Consistent with our original prediction, we also found that people make friends with oppor-
tunistic motives in mind, namely, to get mates and obtain career benefits. In terms of our theo-
retical framework, people have evolved mechanisms that motivate them to establish
friendships. The presence of these mechanisms provides the opportunity for others to exploit
them and, in the pretext of true friendship, to gain opportunistic benefits. Such a scenario
would be damaging for people seeking true friends as it makes them vulnerable to exploitation.
They may end up being surrounded by opportunistic friends, and as such, they may not gain
support in times of need. These costs would translate into selection pressure on individuals to
evolve mechanisms that would enable them to screen out such friends. Future research could
attempt to identify and study these mechanisms.
The two domains we have extracted could be interpreted as reflecting two broader strategies
that individuals employ when making friends, namely, to have people around who would be
available to offer social input and support and to gain opportunistic benefits. We also found that
more than one in three participants indicated a mixed strategy, meaning that they would make
friends because they were interested in true friendship, as well as to gain opportunistic benefits. It
may be the case that, for most people, obtaining true friendship constitutes a long-term strategy,
whereas the opportunistic strategy is activated as a situational strategy. For instance, not having
an intimate partner may trigger an opportunistic strategy that would help individuals to find part-
ners, and they would stop using this strategy when they manage to do so. Further research in the
area is necessary to enable us to understand when people adopt each friendship strategy.
As originally predicted, women were more strongly motivated to make friends to receive
support and social input, whereas men were more strongly motivated to make friends to gain
mating benefits. In addition, men are more career oriented than women (Hakim, 2001; Sweet,
Sarkisian, Matz-Costa, & Pitt-Catsouphes, 2015), which could explain why they were more
strongly motivated to make friends to obtain career benefits. Furthermore, consistent with our
original prediction, younger participants indicated a stronger motivation to make friends to
receive support than older participants. We also found that older participants indicated a stron-
ger motivation to make friends with someone who had desirable traits. One possible explana-
tion for this finding is that, as people get older, they come to realize through experience that
traits, such as a good character, are highly important in a prospective friend.
Our results are consistent with other findings in the domain of friendship. More specifically,
we found that people are motivated by specific factors to make friends. It follows that, if a
friendship does not satisfy these factors, it will be more likely to end. Our findings suggest that
people make friends to have around them others to socialize with, which predicts that, if friends
are not around, friendships will not last. Consistent with this prediction, Rose (1984) found that
physical separation (e.g., moving to a new house or city) was one main reason why friendships
end. Moreover, people are motivated to have friends to have around people who would support
them, which predicts that friendships would end if a friend is not supportive. Consistent with
this prediction, studies find that betrayal constitutes a common reason for terminating a friend-
ship (A. L. Bleske-Rechek & Buss, 2001; Rose, 1984; Sias, Heath, Perry, Silva, & Fix, 2004). In
the same vein, people are motivated to make friends with individuals who have desirable traits
such as compatibility, which predicts that they would be likely to terminate friendships with
individuals who lack such traits. Consistent with this prediction, A. L. Bleske-Rechek and
Buss (2001) found that a lack of common interests is one common reason to terminate a
friendship.
APOSTOLOU ET AL.11
The factors we have identified in the present research would also be reflected in the quali-
ties that people desire in a friend. One study analyzed participants' answers to the open-ended
question “What qualities do you look for in a close friend?”(Roberts-Griffin, 2011). People are
motivated to make friendships to have people around to support them, and accordingly, this
study found that supportiveness and loyalty were among the most commonly reported traits. In
addition, traits such as honesty, humor, and shared interests were among the most commonly
reported ones, indicating that people are motivated to make friends with individuals who have
desirable traits. Communication and presence were also frequently reported, suggesting that
people wanted to have others available with whom they could socialize.
Our study was conducted in the Greek cultural context, and its findings may not be readily
generalizable to other cultural contexts. We believe that the factor structure would most proba-
bly be similar in other cultural settings; however, the importance ascribed to each factor is
likely to differ. For instance, the Greek culture is relatively collectivistic, ascribing more empha-
sis on personal relationships and less on material gains. Accordingly, if this study was to be car-
ried out in a more individualistic and materialistic culture, such as the United States, we would
expect that factors such as career and mating would receive higher scores and factors such as
support lower scores. Similarly, in the Greek cultural context, social welfare systems are moder-
ately developed, which means that, in times of need, people have to rely on their families and
friends for assistance and support, which explains why the support factor received relatively
high scores. Yet, if the current research were to be repeated in countries such as Sweden, which
have very well developed social welfare systems, we would expect that people would place less
emphasis on the support factor. Future research needs to replicate our findings in different cul-
tural contexts and examine cross-cultural variation and also consistency.
Moreover, future studies could attempt to conceptually replicate our findings using different
methodologies. In particular, participants could be asked to consider their current friendships
and report the reasons that have motivated them to form these friendships in the first place. In
addition, future research may examine the connection between the factors we have identified
here and friendship satisfaction. For example, we would expect that people would be less satis-
fied if their friends did not provide adequate social input. Future research needs to also examine
the impact of additional variables such as personality on the factors motivating people to make
friends. For instance, we would expect that people who score high in Machiavellianism
(Jakobwitz & Egan, 2006) would be more likely to be motivated by opportunistic reasons for
making friends than low scorers (Lyons & Aitken, 2010).
The current research is not without limitations. To begin with, our study was based on self-
reported data, which are appropriate because people can convey a vast amount of information
about themselves (McCrae & Costa Jr., 1999). As Paulhus and Vazire (2007) argued “no one else
has access to more information than oneself, and that this information is rich with motivational
and other introspective details that others might not be aware of”(p. 227). However, as with
every other methodology, using self-report instruments has limitations. Kagan (1988) argued
that people do not possess the kind of self-awareness about why they do the things they do,
which is assumed in self-report measures (see also T. Wilson & Nisbett, 1978). One possible rea-
son is that cognitive hardware has evolved to distort reality to protect people's self-esteem and
enable them to achieve fitness-increasing goals (Trivers, 2011). In addition to this issue, it is also
likely that social desirability bias may have also influenced responses. As a consequence of lim-
ited self-awareness, the means of the items and factors comprising the opportunistic domain
are likely to be underestimated, whereas social desirability bias may result in the means of the
items and factors comprising the true friend domain being overestimated. Finally, the study
12 APOSTOLOU ET AL.
examined only the effects of sex and age, and future studies need to extend our work by taking
into consideration other variables.
Making friends is a complex and surprisingly understudied phenomenon. The current
research identified 41 perceived reasons why people make friends and taxonomized them into
broader factors and domains. Considerably more research is needed, however, if this fascinating
facet of human behavior is to be understood.
DATA AVAILABILITY STATEMENT
As part of IARR's encouragement of open research practices, the authors have provided the fol-
lowing information: This research was not preregistered. The data used in the research are
available. The data can be obtained by emailing Menelaos Apostolou: m.apostolou@gmail.com.
The materials used in the research are available. The materials can be obtained by emailing
Menelaos Apostolou: m.apostolou@gmail.com.
ORCID
Menelaos Apostolou https://orcid.org/0000-0002-0685-1848
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How to cite this article: Apostolou M, Keramari D, Kagialis A, Sullman M. Why people
make friends: The nature of friendship. Pers Relationship. 2020;1–15. https://doi.org/10.
1111/pere.12352
APOSTOLOU ET AL.15
