One writer tried to disprove Dunbar’s number on Facebook but found that Dunbar was correct after all:

Not for Dunbar, apparently. He was looking for individual interactions. Well, I thought, if that’s all it takes to disprove Dunbar’s number, then that’s what I’ll do: I’ll write personal letters to every one of my 2,000 Facebook friends…

I only made it through 1,000 of my 2,000 Facebook friends. But that was enough. My experiment’s outcome was crystal clear: Dunbar’s number kicked my ass.

In trying to disprove Dunbar’s number, I actually proved it. I proved that even if you’re aware of Dunbar’s number, and even if you set aside a chunk of your life specifically to broaden your social capital, you can only maintain so many friendships. And “so many” is fewer than 200.

Writing my Facebook “friends” had taken over my time. I was breaking plans with real friends to send meaningless messages to strangers. Some of the strangers didn’t respond, and many of those who did respond only confirmed Dunbar’s theory.

Quick examples: When I wrote A. F., a Malaysian magician, he responded: “hey rick i think you might’ve sent me this message by mistake lol.” And when I wrote A.D., a friend of a friend, and asked how things were going, she replied, “Sorrx but do i know you?:)”

The question I want to ask next: so did this writer lose friends over the course of this? If so, was it because the friends did the dropping or the writer decided to pare down his friends list?

While Facebook allows people to have expanded “friendship” networks, it is interesting to consider what would actually happen if someone tried to activate these networks. For example, the friend you once had in third grade and are now are Facebook friends with: what can you reasonably ask that person to do? Respond to a quick message you send them? Catch up with you and talk about what has happened in your lives since you last talked? Help you out of a tough spot? Join a cause you are interested in? Alert you to a job opening that would help you? My guess is that most of these online relationships rarely can be counted on even though they may have a semi-permanent status on Facebook. If this is the case, then perhaps you have hundreds upon hundreds of friends on Facebook but only 150 or so (Dunbar’s number) can be counted as actionable relationships.

This is not necessarily bad for Facebook: perhaps that 150 friends can shift rapidly over time meaning one week someone is a close friend while several months later it is someone else. Or perhaps you don’t actually know which of your friends is part of the 150 until you engage in deeper interaction. To have more social capital, it is helpful to have broader social networks that you can attempt to utilize. Without those connections at all, it is more difficult to find information or produce change.