My pastor recently asked me, “Why is it so hard for people to see pastors as friends and not just pastors?” In one respect, the question caught me by surprise. He is part of a large pastoral staff of a big and vibrant church with a reputation for being highly relational. How can someone whose life revolves around forming caring relationships have a lack of friendship?

It turns out my pastor is far from alone. In a recent study, my team discovered that most relational-style pastors and missionaries average fewer personal relationships than the typical adult, and an alarming number have too few close confidants to support them in their life and calling.

Though it may be tempting to simply encourage ministers to seek more relationships, many ministers are faced with a trade-off between quality and quantity. Those with a large number of very intimate relationships have a smaller overall social network, and those who form lots of relationships have impoverished inner circles. Failing to get the right balance corresponds with burnout and ministry ineffectiveness.

Quantifying an Inner Circle

Our research is rooted in the idea that humans naturally have a certain number of personal relationships to which they gravitate. Known as “Dunbar’s Number” because it was first discovered by British evolutionary anthropologist Robin Dunbar, the number of genuinely personal relationships that we can actively maintain averages around 150 people but varies broadly. Some people can handle more and some less, but 150 seems to be the human norm.

Interestingly, Dunbar and colleagues note that 150 people is both the approximate size of typical small-scale human villages and about the number of people who can live or work together without needing power structures to enforce cooperation. The group is small enough that social pressure can keep people in line.

Within those 150 active personal relationships are rings of ever greater intimacy and trust. Around 50 of those 150 are close friends and family members whom we interact with a little more often and trust a little more. Within those 50 is another ring of approximately 15 very close friends and family members. We turn to these 15 in times of trouble or would drop what we are doing to help them.

Then there is the inner circle of best friends. These five people are the keepers of our darkest secrets, those that we count on through thick and thin, who we would be happy to see every day if we could. Interestingly, around five people is also largest number of people who can be in a conversation in which everyone feels comfortable to contribute.

The Limits of Friendship

The rings of 5, 15, 50, and 150 are typical, but they may not be the best sizes for everyone.

Why can’t we simply have as many friends as we would like? Research by Dunbar and colleagues suggests that we are limited by physical proximity, brainpower, and hours in the day. For relationships to become emotionally intimate, physical touch is our go-to method.

Though we humans do not pick bugs off of each other like chimps do, we do need to “socially groom” each other, and that requires being near each other. Have you noticed that children often brush and braid each other’s hair and love to wrestle? These are acts of social grooming. Positive touch, such as pats on the back and hugs, releases chemicals in our body that make us feel good around that person and inclined to trust them. Laughing with others or acting in synchrony (as when singing or clapping) may do something similar.

Our relational capacity also seems to be limited by brainpower. Humans have unusually large personal social groups proportional to our unusually large brains. Keeping track of lots of individuals—their personalities, their changing likes and dislikes, their friends and foes, their current concerns and struggles—requires a lot of computing power. And while humans have a lot, it is not unlimited.

Of course, our number of relationships is also limited by time. We cannot spend all of our time hanging out with friends and socially grooming them. We need to sleep, work, and meet other basic needs. Working and eating alongside our friends and family can do double-duty, but not everyone has this luxury.

The result of these limits is that if we begin investing in someone new, someone old may drift from an inner ring of intimacy to an outer ring, or from an outer ring out of the active network of genuine personal relationships and into the “acquaintance” zone. We cannot simply choose to have an unlimited number of super-close best buddies.

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