Social Networks Don’t Really Expand the Number of Connections We Can Sustain Over Time*
An important feature of natural social networks in both humans and non-human primates is that they are structured into a distinctive series of hierarchically inclusive layers that have a natural scaling ratio of approximately 3. These layers reflect both interaction frequencies and, at least in humans, emotional closeness. In humans, these layers have values that approximate 5, 15, 50 and 150, and extend beyond this in at least two further layers to 500 and 1500. The first three layers have been identified in several online datasets and, at least in humans, appear to be a consequence of a constraint on available social time combined with a relationship between time invested in a relationship and its quality (as rated in terms of emotional closeness). The two outermost layers (at 500 and 1500) correspond, respectively, to acquaintances (people we would not consider as personal friends or family, but know well enough to have a conversation with) and to the number of faces we can put names to.
The fact that social networks remain about the same size despite the communication opportunities provided by social media suggests that the constraints that limit face-to-face networks are not fully circumvented by online environments. Instead, it seems that online social networks remain subject to the same cognitive demands of maintaining relationships that limit offline friendships. These constraints come in two principal forms: a cognitive constraint derivative of the SBH (social brain hypothesis) and a temporal constraint associated with the time that needs to be invested in a relationship to maintain it at a requisite level of emotional intensity. We can only interact coherently with a very small number of other people (about three, in fact) at any one time. It seems that even in an online environment, the focus of our attention is still limited in this way.
HT to John Hagel over on Twitter