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Why Dunbar's Number is Irrelevant

For those of you not familiar with Dunbar's number it basically says that the most amount of people that you can maintain stable social relationships with is 150.  According to wikipedia:

“Dunbar's number is a theoretical cognitive limit to the number of people with whom one can maintain stable social relationships. These are relationships in which an individual knows who each person is, and how each person relates to every other person.Proponents assert that numbers larger than this generally require more restricted rules, laws, and enforced norms to maintain a stable, cohesive group. No precise value has been proposed for Dunbar's number, but a commonly cited approximation is 150.”

There have been several folks such as Chris Brogan who have talked about “beating Dunbar's number,” but there is no need to do so and in fact I believe the whole discussion around this number as it related to social media and online networks is a bit irrelevant.

I recently finished reading Morten Hansen's fantastic book on Collaboration in which he states that the real value of collaboration and of networks doesn't come from strong relationships and networks but from weak one's.  In fact one of Morten's network rules is actually “build weak ties, not strong ones.”  According to Morten:

“But research shows that weak ties can prove much more helpful in networking, because they form bridges to worlds we do not walk within.  Strong ties, on the other hand, tend to be worlds we already know; a good friends often knows many of the same people and things we know.  They are not the best when it comes to searching for new jobs, ideas, experts, and knowledge.  Weak ties re also good because they take less time.  It's less time consuming to talk to someone once a month (weak tie) than twice a week (a strong tie).  People can keep up quite a few weak ties without them being a burden.”

When trying to think of the strong ties that I have I can maybe come up with just a handful, nowhere near approaching Dunbar's number of 150.  In fact I doubt many people have anywhere near 150 strong ties.  Read the definition of Dunbar's number above carefully to really understand what is being said there.  Now, when I think about how many weak ties I have, well then it far exceeds the 150 number, but then again these weak ties are not “stable social relationships where I know who each person is and how each person relates to every other person,” therefore even referring to Dunbar's number in this case is a moot point.

I have around 1k+ linkedin connections, 1k facebook friends, and over 4,300 twitter followers.  A very tiny portion of these people are strong ties.  What social networks have allowed us to do is to build massive networks of weak ties.  I use these weak ties all the time to reach out to folks for guest articles, business requests, speaking engagements, or ideas and advice.  The mere fact that we are connected to people online creates a type of weak tie because you can always reach out to the person you are connected with.  This is something I do quite a bit when I'm traveling.  I take a look at my network to see who I'm connected to in a particular geographical area, then I reach out to that person and try to arrange to meet in person.

We shouldn't be trying to figure out how we can maximize the number of strong relationships we can build or how we can beat Dunbar's number; that task is as fruitless as it is irrelevant.  Build weak ties where you can because they are extremely valuable, more so than strong ties.

Your thoughts?

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  • Feb 27 Posted 5 years ago jimeffect

    If this is true, that might explain why Twitter and Facebook is so successful at helping people gain new workign relationships, or for companies to manage their reputation. There are weak ties abound in social media platforms, and those add up to form a strong circle for opportunities. Now I know that having plenty of weak links with people can actually have a positive effect on leads and opportunity.


  • Sep 27 Posted 5 years ago wkwami (not verified)

    You make a good point, Ipagan. However, by segmenting people into groups and then reaching the them through their group leaders, you essentially turn the leaders into gatekeepers for better or for worse. Also, small groups are prone to being qliquish, subjecting individual ideas and opinions to "group-think". The very thing that makes small towns friendler also makes them prone to conformity and the suppression of dissent and new ideas. I find the "weak link" concept interesting if only for the fact that it sidesteps the gatekeeper.

  • Sep 16 Posted 5 years ago TheEggOfTruth (not verified)

    On Dunbar's number - Does.Any.Of.This.Matter.That.Much? There's obviously only so much time a person can develop relationships in and therefore a rough limit to the number of close mates you can have. It's not about who you'd have coffee with, it's about who you'd go into battle with, who you'd sacrifice things for. Rather a hundred attend my funeral than a thousand like my status update.

  • Mar 24 Posted 6 years ago Laurie Dillon-Schalk (not verified)

    Ipagan -

    The wiki calls it a 'theoretical cognitive limit to the number of people with whom one can maintain stable social relationships"  - which I'm not interpreting as cohesiveness, though  - I agree with you that this is a key aspect in a physical social setting.  

    In the sense that it is a cognitive limit - I do expect this can be applied to a social / virtual networks. 

  • Mar 23 Posted 6 years ago Paul Cunningham (not verified)

    Hi Louis,

    Thanks for adding some rigour to this discussion.



  • lpagan's picture
    Jan 5 Posted 6 years ago lpagan Dunbar's number has nothing to do with networking, weak ties or strong ties, relationships or social media. If you read the wiki closely it really has to do with the cohesiveness functionality that we as individuals can comfortably handle while being part of a larger group for a sustained period of time such as a business, village or town. After this number is passed social breakdowns begins to emerge. Why do you think in small towns people are usually friendlier toward one another than in big cities - think of people saying Hi in each setting. If we must, I like Brogan's idea of 'segmenting' groups of ppl by location and setting out to connect w those group leaders of said groups. In essence, those heads of networks will become your 150, and through them you will access the rest of their networks, and not necessarily 'live' within each network and keep Dunbar's theory in tact.
  • Jan 5 Posted 6 years ago Inquisigal (not verified)

    Interesting take on weak vs. strong ties; I do agree that weak ties definitely aid in professional relationships, business networking and other projects. However, I do think that the "friends" and "stable social relationships" issue needs to be further studied, as I do believe there is a big difference between say, one's Linked In connections, and the "friend's" one keeps in touch with via Facebook, as well as a big difference between connections or friends you have conversations with in person or online, versus people we just click on to make a "connection."

    I think it's perhaps overly idealistic to think someone you have a very cursory connection with online is going to do much in the way of aiding in your professional needs - unless, of course you're a writer putiing a post out looking for sources or story information. Your average person just doesn't spend the same amount of time online - and therefore paying attention to who their connections are, and what they are doing on a daily or even weekly basis - that say, a person who works in media does. And though Dunbar's study doesn't relate to humans in the modern world, it's worth noting that people are indeed getting out of control with their fishing online for friends and connections, and reveling in the narcissism of how many people they can list as "friends" and "connections" at the expense of making more useful, reality-based connections with people who really understand their skills and vision professionally - and know them and would feel strongly about helping them get a leg up - as well as their personalities and qualities as a friend.

    I suppose it depends on personal preference, too - is your life all about work and self-promoting, or do you work, and make time for real friends, hobbies, sports, etc? It honestly kind of makes me sad to envision how all of these constant online networkers live their lives - when there's so much more to be gained in maintaining a balance.

  • Dec 16 Posted 6 years ago Supplier Joe (not verified)

    I wish friendships in real life could be as surfacy as they are on FaceBook and other social networks.

  • JacobMorgan's picture
    Jan 26 Posted 7 years ago JacobMorgan I think this is the second time where I tried to respond to everyone's comments in a post and then for some reason it didn't save, so sorry again!  Thanks for all of the great comments though, lots of interesting discussion.  Would be happy to keep it going on twitter @jacobm (sorry just dont have the energy to re-type all my responses to all of you!)
  • Jan 26 Posted 7 years ago JimMatorin


    I am a stong advocat of Dunbar's number.  A topic I have addressed on my blog: 
    http://bit.ly/5Syg5I  Your point about weak ties is interesting and helfpul.  However, I totally disagree with your conclusion.  When I travel I always make it a point to connect with strong ties.  Strong ties bought me to the party and with six degrees can lead me anywhere.  A strong tie is like enjoying a big bottle of red vs. weak tie which is bag in the box table wine.  Then again it depends on your networking philosophy.  I also do not understand Beto's comment.  Can't trust Dunbar?  Does that mean we throw out all the Anthropological evidence that has been gathered as it relates to tribes, religious communities, military, etc.  Social media is good stuff, it is now, but we need to always respect and learn from history.

  • Jan 25 Posted 7 years ago EricFulwiler I like the thinking behind this post, but I am going to have to point out a few issues with it. I completely agree that in building our professional lives (what i like to call our personal brands) these weak ties are more important and applicable than strong ones. People get jobs, clients, etc from usually second and third ring friends. But where Dunbar's number is very relevant is in management. Organizing and running a company or a team is very different than organizing or running social or professional connections. In that case, Dunbar's number makes much more sense, and the theory usually holds up.
  • Jan 25 Posted 7 years ago lauriedillonschalk1

    Jake -

    I appreciate your post as few have spoken about Dr Dundar's no. and the description of strong vs. weak ties better describes the differences between what Dr. Dunbar meant by the 150 limit of strong tie relationships and what we are seeing with large social networks.  [it is worth mentionning that Dr. Dunbar was an anthropologist studying tribe size in mammals)

    Social networks have finally given us a training ground for exercising the upper limits of both strong and weak tie relationships.  We now have an "active" network size - which is likely less than your 1K linkedin, 1K friend and 4,300 followers.  The active network is what counts - because you can't have a weak tie to someone that doesn't use the network.  This was nicely described by an article published in the Economist using a Facebook's in-house sociologist testing to see if Dr. Dunbar's number was still relevant.  The links of which are found in a 2009 blog post of mine as the Economist article may be behind a subscription wall now.

    I think what the Economist article lacks is an examination of our use of categorization to manage our active network sizes.  I can manage several large active networks because they are in different areas - twitter, youtube, linkedin, facebook, etc. 

    What i do like in your article though is the description of weak tie relationships.  Managing a great number of casual relationships does bring ample opportunity.  Agreed. 

  • Jan 25 Posted 7 years ago JasonLauritsen Really good post.  Social media has really given us the opportunity to cultivate our weak ties in ways that weren't even possible in the past.  However, I'm not sure that the answer is to turn our focus to building weak ties instead of strong ties, but to do both and recognize each as unique and serving different roles as part of our social capital. 
  • robertpaterson's picture
    Jan 25 Posted 7 years ago robertpaterson Jake, Dunbar is as much a theory as gravity or light = the science is there.

    But you are correct about the value of weak ties - they are as you say very useful.

    But if you wish to have influence, the Trust is the key.  You also have huge leverage inside the parameters of Dunbar. Say you have only 4 close friends and they have 4 close friends - this is the leverage:

    2 – 16

    3 – 82

    5 – 625

    8 – 4,096

    13 – 28,561

    34 – 1,336,336

    55 – 9,150, 625

    89 – 62, 742,241

    144 – 429, 981, 696

    So even with your paltry 144, the actual Number by the way, you can reach 429 million people. Enough I think?

    The leverage is very useful with the 34 to 89 levels. between 1.3 million and 62 million.

    It is not the number Jake is the quality and the Trust in the relationships that enables us to use social media to make a difference.

  • Jan 25 Posted 7 years ago BetoAndrade (not verified) Jake, good call. You can't trust Dunbar.  You can fudge it, fake it. Nobody talks margin of error like in opinion polls. Like they say in the meatspace, dude... let's do lunch, eh.  I'll take some virtual Heinz ketchup on my virtual Simplot fries :)

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