Dunbar’s number and warp drive: Building your social network beyond 150

Ian Lurie

This is really, really geeky stuff for a Friday. Plus, I had to dig waaaay back to my college Sociology courses to figure it out.

You’ve probably heard a lot about the fact that a person can only maintain relationships with 150 people before their brains are frappe’d into cottage cheese. It’s a valid assumption. Try to keep actively in touch, day-to-day, with more than 150 people. It’s hopeless.

That 150-person limit is called Dunbar’s Number. It’s like the speed of light (C, if you’re a hardcore geek): Current physics says you can’t exceed the speed of light. You get more and more massive as you approach it, until you reach near infinite mass and implode, or slow down, or something. The scientific term is ‘foomp’.

Image courtesy of Gizmodo.com, and with infinite respect to Gene Roddenberry.

Dunbar’s number works the same way. As you approach it, your rolodex gets heavier and heavier, until it implodes and no meaningful conversation can escape. Foomp.

Before you say ‘Oh, 150 people doesn’t sound like much’, imagine what it looks like:


But, just as we learn in Star Trek, you can beat the speed of light by cheating: Instead of going faster than light, make the trip shorter by rending the fabric of space. Hey, I’m not making this up.
You can beat the 150-person limit that Dunbar imposes by using social media as your warp drive.

Social Networking: Dunbar’s Warp Drive

Social media lets you bust past Dunbar’s number.

The 150-person limit only applies to your egocentric network. That’s the people you personally know.

You can bring a far, far larger number of people within your circle of influence by carefully choosing those 150 people. If everyone one of your 150 people has meaningful conversations with another 150, that’s (removing socks and shoes so I can count with my toes) 22,500 people. And if that second layer knows another 150…

And so on. Your network connects you to other networks, and it all expands, really fast.

Bam. Warp 9, Scotty.

Know who you know

I’m not suggesting that you exclude your friends from your egocentric network simply because they’re not popular. This isn’t Junior High.

I would suggest that you know who you know, and help them out. Chris Brogan covers this really well in his book, Trust Agents: Build relationships with bloggers, Tweeters and heck, even normal people that you like. Help them get connected within your network. They’ll remember the help, and make sure they’re a conduit from your egocentric network to theirs.

The social media rolodex

Create yourself a social media rolodex: Keep your 150-member network there, with important dates, their goals as you know them, and even a reminder to let you know when you should check in with them.
‘Check in’ could just mean reading their blog. Don’t pester. But, if they need help, and you can give it, go for it! Keep your Dunbar network in order.
OK. My brain is now properly frappe’d. Time to head into the weekend.

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  1. I don’t think you need to limit your helpfulness to people within the tight knit 150 person group. As long you are genuine in your desire to be of assistance and not looking for a return of the favor, I think it’s ok to check in with folks on the edge of your network.
    So that begs the question:
    How can we help Ian in 2010?

  2. Hi Ian… good point. Thanks for the book recommendation.
    I’d add one more idea: use email filters and Twitter groups. Organizing your messages in categories helps to ready yourself to send and receive updates to specific sets within your contacts.

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