Dunbar's Number - 148

"a theoretical cognitive limit to the number of people with whom one can maintain stable social relationships."


"Proponents assert that numbers larger than this generally require more restrictive rules, laws, and enforced norms to maintain a stable, cohesive group."

"a direct function of relative neocortex size."

"Dunbar's surveys of village and tribe sizes also appeared to approximate this predicted value, including 150 as the estimated size of a neolithic farming village; 150 as the splitting point of Hutterite settlements; 200 as the upper bound on the number of academics in a discipline's sub-specialization; 150 as the basic unit size of professional armies in Roman antiquity and in modern times since the sixteenth century; and notions of appropriate company size."


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