This pattern models the abstract structure of circular causality where system outputs influence system inputs through a closed loop of cause and effect. The boundary encompasses the complete cycle from state detection through response generation to state modification and back to detection. The pattern assumes that information flows in a closed circuit, that there are identifiable cause-and-effect relationships between components, and that the system can be meaningfully described in terms of states and changes over time.
The dynamics inside the boundary include the continuous circulation of influence through the loop components, the accumulation or dissipation of changes based on loop polarity, and the potential for delays to create complex temporal behaviors like oscillation or overshoot. Outside the boundary are external disturbances to the system, the specific domain content of what is being measured or changed, and the detailed mechanisms by which detection or response occur - these are considered environmental factors or implementation details.
The pattern assumes that feedback effects are significant compared to external influences, that the loop structure remains relatively stable over the time period of interest, and that the system exhibits some form of measurable state that can be both monitored and modified through the feedback process.