Dunbar’s number is defined as the number of people in our network we can have stable social relationships with. It’s the limit where an individual knows who each person in the network is, and how each person relates to every other person in the network. British anthropologist Robin Dunbar, for whom the number is named, proposed humans can comfortably maintain 150 people in their network. He explains the degree of social intimacy as: “the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar.”
One example of the theory in action in the business world comes from GORE-TEX founder Bill Gore. He found once a building had more than a certain number of people they were less likely to work together as a team. So, he would build another building. And another. And another. At GORE-TEX, no business units were allowed to grow beyond a certain size. Bill believed “you have to divide so you can multiply”.
In the age of social networks it seems daunting to create relationships that matter. It’s not unheard for users to have thousands of ‘connections’ on LinkedIn, Facebook, Twitter, Instagram etc.
The Network of Networks
Before you run off and lock down your social to just 150 of your nearest and dearest, I recommend reading a blog post titled Maintaining Relationships: The Fallacy of Dunbar’s Number by Brad McCarty.
Brad expands on the theory by using what he calls ‘Buckets’. Like Gore’s buildings, Brad is able to maintain better relationships by breaking his contacts into smaller buckets. After reading about Bill Gore, Brad reorganized the 3,160 contacts in his network based on tags with titles like CEOs, VCs, Angel Investors, Media etc.
Brad’s network is less stove-piped than the GORE-TEX factory example. He noticed people in the network often crossed into multiple tags with some people belonging to up to five different tags. However, lending credence to Dunbar’s Number, Brad found there wasn’t any one tag with more than 150 people assigned to it.
Brad acknowledges he might not be at the ‘have an uninvited drink at the bar’ level with his network, but by using his tag system, he’s got almost 2,500 people he knows well and keeps in touch with on a regular basis. He says if your handle your buckets correctly, your networks can be sustainable and add value.