Nugget of Knowledge: Dunbar’s numbers

The rule of 3 applies to true friends


YOUNGSTOWN, Ohio (WYTV) – Anthropologist Robin Dunbar discovered groupings of 150 nearly everywhere he looked.

Clans tend to have 150 members.

Whether you’re talking about a unit of soldiers, an Amish community or a company with employees, when a business grows larger than 150, it tends to build a new office.

Dunbar discovered that the number grows and decreases according to a precise formula, roughly a “rule of three.”

The next step down, 50, is the number of people we call close friends – perhaps the people you’d invite to a group dinner. You see them often, but not so much that you consider them to be true intimates.

Then there’s the circle of 15, the friends that you can turn to for sympathy when you need it, the ones you can confide in about most things.

The most intimate Dunbar number, five, is your close support group. These are your best friends (and often family members).

On the other side: 1,500 seems to be the limit for most people when it comes to putting a name to a face.

Your five closest today may not be your five next week; people come and go.

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