Hierarchies may be natural, for example, birth order in a family, or arbitrary, as is the case in a designed system, such as a school or business. Arbitrary hierarchies require more energy to maintain than do natural hierarchies, and they frequently divert energy from goal attainment. For example, maintaining the age-grade hierarchy is schools can be shown to be counterproductive in many cases. Russell Ackoff suggests the most elegant way to handle a problem is to dissolve it. A second important characteristic is homeostasis, which refers to self-regulation through feedback mechanisms.
Machines are relatively simple systems with few variables, which operate in a stable relationship.
Mechanical systems require little feedback from the environment to function. At the other extreme, organic systems are very complex with many variables, which require a great deal of feedback. The larger and more complex the system, the more energy, in the form of feedback, is required to maintain a dynamic balance among elements. A final characteristic of a system is it purposiveness. We have attempted to treat education as a unitary system, but in reality it is highly pluralistic with many conflicting goals.