*sorry; I saw Roger Waters’ 2012 production of The Wall last night and am feeling a bit anti-establishment.

“In this paper we analyze a dataset of Twitter conversations collected across six months involving 1.7 million individuals and test the theoretical cognitive limit on the number of stable social relationships known as Dunbar’s number. We find that the data are in agreement with Dunbar’s result; users can entertain a maximum of 100–200 stable relationships.”

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0022656

What is really interesting is how, throughout history, broadly similar numbers turn up, time and time again, in the organisations of military units. Even today infantry are organised into fire team / squad / platoon / company / battalion, roughly corresponding to the five lowest “circles of intimacy”. Coincidence? Or primate psychology?

Dunbar is not talking about the sort of relationship you are referring to, I think.

Iain, one of the problems with Dunbar’s first paper in 92 (IIRC), or perhaps the conference papers that got circulated before that, was that everyone complained about the groups of primates he included. I think there’s a good argument for treating NWP and OWP separately, given that they have a very deep evolutionary split. With respect to social evolution, most (with adjustments) OWM’s and apes are polygynous and have fission fusion group structures, etc. while most NWM’s are monogamous or polynadrous and/or have much tighter group structure. I would argue that a “number” that worked for both groups is spurious.

we do maintain knowledge of that size of a group of people often by representing their role in our lives as a symbolic fact. This is something we can do because we use language. And that is why Dunbar’s argument started off. He was using it in an argument about the emergence of language, but I suspect the logic of that argument is the wrong way around too. But, hey, it is really interesting and I wish I had thought of it.

Right, exactly.