The Dunbar Number, From the Guru of Social Networks - Businessweek

The Dunbar Number, From the Guru of Social Networks - Businessweek: In the same way that human beings can’t breathe underwater or run the 100-meter dash in 2.5 seconds or see microwaves with the naked eye, most cannot maintain many more than 150 meaningful relationships. Cognitively, we’re just not built for it. As with any human trait, there are outliers in either direction—shut-ins on the one hand, Bill Clinton on the other. But in general, once a group grows larger than 150, its members begin to lose their sense of connection. We live on an increasingly urban, crowded planet, but we have Stone Age social capabilities. “The figure of 150 seems to represent the maximum number of individuals with whom we can have a genuinely social relationship, the kind of relationship that goes with knowing who they are and how they relate to us,” Dunbar has written. “Putting it another way, it’s the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar.”