Introduction to ‘Friends’ by Robin Dunbar

Introduction to ‘Friends’ by Robin Dunbar

This is the first in a series of blog posts on Robin Dunbar’s book “Friends”. Dunbar is an evolutionary psychologist who worked at Oxford University. In this book he helps us understand the power of friendships and explores some of the social and biological realities involved.

Robin Dunbar came up with the idea of Dunbar ‘s number, the maximum number of friendships we can sustain. He had been studying monkeys and primates, and became convinced that the time spent grooming was for social purposed not as was widely thought for hygiene. To test this, he plotted time spent grooming against body size and monkey group size. This confirmed that it was social group not body size that was correlated with time spend grooming, so that grooming is primarily functioning to bond together monkeys. Extrapolating from his data on monkeys and other primates, plotting brain size against group size led to a prediction based on human brain size that humans would have a maximum friendship group size of 147 (often rounded up to 150). Other research has since confirmed that somewhere around 150 friends is typical for human beings. In order to keep friendships alive (and Dunbar is particularly interested in the group who would help you out practically if it was costly), time needs to be invested, and since we have limited time we can only keep a limited number of friendships going.

Dunbar sets out circles of friendship, each outer ring including all previous circles. So we have 1-2 very close friends (men tend to have just their spouse, women their spouse and their best friend). Then 5 close friends (the support group), 15 best friends (the sympathy group), 50 good friends, 150 friends, 500 people you are familiar with (this is especially those you work with), 1500 whose names you know, and about 5000 faces you can recognise.

There is a well-established kinship premium (family members are much closer than the amount of time you spend with them would suggest). There also appears to be a workplace/ commercial discount- the majority of people you spend hours a week with at work are not people you will keep seeing if you stop working, despite spending many hours with them.

The book is full of fascinating anthropological, psychological and neuroscience information. This little series of blog posts will try to pull out some things that seemed interesting in relation to church in particular.