My Three Cents

Dunbar’s number is “a suggested cognitive limit to the number of people with whom one can maintain stable social relationships,” according to Wikipedia. “These are relationships in which an individual knows who each person is and how each person relates to every other person.”

Popularized by anthropologist Robin Dunbar, this concept has long been of interest to me. Researchers claim this number lies between 150 and 250; however, they have never reached a consensus on an exact figure.

Regardless, I have seen in my own personal experience that this phenomenon exists, when I have the occasional awkward social moment and forget meeting someone. It does not mean the interaction isn’t important.   I feel it’s simply a product of the limitations of the human brain. 

If you empathize with this condition and recognize the existence of Dunbar’s number, here are a few ways to maximize your relationships and interactions … especially given our sadly finite capacity to retain them in our memory.

Relationship Opportunity Cost

Now that we’ve established that we can only handle so many relationships, then it’s a good strategy to pick and choose them wisely. This may sound somewhat harsh, but it might be time for a “relationship audit.” Figure out who inspires and motivates you. Conversely, identify those who bore you or stress you out. Find ways to spend more time with the people who are positive influencers and decrease the bandwidth given to those who could have negative effects.

People Are Spare Parts for Ideas

Diversity in your network is extremely important for fostering creativity and innovation. It was author Steven Johnson who first introduced me to the notion that people are spare parts for ideas. What does that mean? Say you have a doctor, a banker, a social worker and a third grade teacher in a room. Each of these people possesses a special knowledge or skill set that the others in the group do not. By enabling members of this group to interact with each other, they now have access to new knowledge pools. Perhaps they can see a problem differently or tap the group’s experience to solve it. The possibilities are endless and some of the most innovative companies, like IDEO, operate on this principle.

The Internet Is Dunbar’s Multiplier

While it’s extremely difficult to maintain hundreds of personal relationships, the internet has made the task a little bit easier. Sure, emails are not the same as handshakes — but they give us the ability to keep track of our relationships more efficiently.  The world wide web also enables us to easily find people with the knowledge we need. Finally, social media is a catalyst for multiplying your personal Dunbar’s number. With LinkedIn you can keep track of contacts, on Quora you can crowdsource a question and with Twitter you can follow smart people sharing smart ideas.

thought leadership


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