Emergence is an important occurrence in social systems ranging in size from small families to large international organizations. Emergence takes place when the whole is more than the sum of its parts. More carefully: A property is emergent when it belongs to a whole but not to its parts, and is not just an aggregate of the properties of the parts because it results from the interactions of the parts. For example, a university has the property of granting degrees, even though none of its parts (employees, buildings) has this property.
Many people have noticed the importance of emergence in complex systems, but I haven’t seen any discussion of its opposite, which I will call demergence. A system is demergent if the whole is less than the sum of its parts, that is, if the interaction of the parts prevents the whole from having valuable properties that it otherwise might have. My current favorite example of a demergent system is the U.S. Congress, which has many talented people but is failing horribly to pass legislation because of toxic behaviors and interactions. For example, the Republican-controlled House of Representatives has voted more than 30 times to repeal President Obama’s Affordable Care Act, but cannot work with the Senate to deal with ongoing economic problems. Of course, the problem with the House of Representatives is not just interactions, because some of its parts (members) have serious ideological defects.
Other examples of demergent systems include sports teams such as my favored Toronto Blue Jays baseball team, which has many talented players but loses a majority of its games. There are also demergent families in which hostile interactions prevent the family from functioning well as a whole. Good research collaborations have emergent properties when people work together to produce articles and books that are better than the individuals could have done on their own. But collaborations can also be demergent, if individuals do not have the intellectual flexibility to build new ideas rather than stick with old ones and waste each other’s time.
The brain is a marvel of emergence. I am currently working on a new theory of consciousness that explains it as the result of three neural mechanisms: representation by patterns of firing in neural populations, binding by neural processes that combine representations into new ones called semantic pointers, and competition among semantic pointers to represent the most salient aspects of the current situation. Each of these mechanisms has emergent properties. A group of neurons can form representations more complicated than one neuron can do on its own, and a representation formed by binding can go beyond the representations out of which it was formed. For example the concept of zero cannot be based on perception, but can come about by combining the concepts of quantity and absence. Semantic pointer competition has the extraordinary emergent property of consciousness, the feelings that we experience when representations such as perceptions, emotions, and thoughts win out over their competitors.
When brains malfunction, however, they can have demergent properties. In epilepsy, individual neurons fire appropriately, but the whole brain develops abnormal patterns that can lead to unconsciousness or convulsions. The defective interactions of the neurons prevent the brain from having its normal properties of consciousness and proper functioning. Figuring out how to have emergence replace demergence is important for neural functioning, and also for effective social functioning.