Cognitive Limits and Group Size

Revised Topic Oct 2008

I am considering some of the arguments debated during the Canadian and US federal elections in 2008. Here is my perspective:

I assume that each human has limited cognitive ability and will only be competent in the performance of a limited number of tasks. I am not convinced that elections select the most competent people for the very demanding tasks of governing. I am not suprised when politicians rely on dogma and slander as they attempt to win the popular vote. I am sure that our current election methods are obsolete and need to be replaced with more sophisticated methods of achieving representational government. The quality of election-time argument is poor. The policies being promoted lack detail and often are not credible solutions to problems that have deep roots in human nature.

Dunbar and others established an important relationship between brain size and cohesive group size. The basic idea is that the cohesion of primate groups is limited by the information-processing capacity of the neocortex. One human can only maintain social and working relationships a limited number of individuals by meaningful personal contact. In simple terms, you can only know a small number of people well enough to understand their individual characteristics, to evaluate what they are likely to do and to develop cooperative work habits. You can only form intimate contacts with a few select individuals.

Each human has a people sphere around them with a central region of intimates and a peripheral region of acquaintances. Just as there is a range of human cognitive ability, there is a range of human social ability. The most gifted humans have larger people spheres that might include up to 150 people. Beyond the boundaries of the known-people sphere, other humans blur into an undifferentiated “public.” Humans can recognize more than 150 faces, but the faces are often nameless and meaningful associations are obscure or absent.

Less socially gifted humans have difficulty maintaining connections with a smaller number of people and may not be able to sustain even one intimate relationship.

Dunbar states: ‘overnight camps can readily be identified as demographic units in time and space and the tribal groupings can be identified either by linguistic homogeneity or geographical location, the intermediate level groupings are often defined more in terms of ritual functions: they may gather together once a year to enact rituals of special significance to the group (such as initiation rites), but for much of the time the members can be dispersed over a wide geographical area and, in some cases, may even live with members of other groupings. …”

Most primates live in complex, multi-tiered social systems in which different layers are functional responses to different environmental problems. Chimpanzees, like humans, have a fission/fusion form of social system. The community is divided into a number of temporary foraging parties whose composition changes with changes in the environment. A larger group may divide into smaller foraging groups when food is scarce. Smaller groups may fuse when food is abundant or when an external threat makes alliances more attractive.

The cohesion of primate groups is maintained by grooming each other. Body contact and grooming establishes and services friendships and coalitions. Coalitions protect their members against harassment by the other members of the group. The more harassment an individual faces, the more important coalitions are. A coalition’s effectiveness is measured by its members' willingness to come to each other's aid and is directly related to the amount of time its members spend grooming each other.

An emergent idea is that smaller groups based on kinship and affinity work better and larger groups require formal external structures that define and enforce specific roles and behavior. In modern businesses, smaller work groups increase job satisfaction and allow the coordination of tasks and information-flow through person-to-person links. In some high tech software companies, smart and nice employees are happiest working in a village atmosphere that includes children, pets and combines work with play. In contrast, highly regimented and anonymous work environments disconnect employees from every other expression of their lives and produce “alienation”, a common feature of urban life.

This discussion in continued Group Dynamics by Stephen Gislason.