Characteristics of a System

Unfortunately, the phrase "negative feedback" is sometimes used loosely as a synonym for "criticism," particularly in education. When talking about systems try to keep in mind that negative feedback is not necessarily good or bad. It is simply a process that negates changes or disturbances in the system. Any system that is going to survive long enough to be an important part of our environment has to have the ability to cope with any kind of change and survive it. All stable systems get this self-stabilizing ability from negative feedback loops.

Negative feedback loops are everywhere, in every part of our natural and social environment. If we understand how they work, we will have a tool that will help us understand all kinds of systems. The easiest way to get a feel for how negative feedback works in a system is to consider one in action.

For example, the thermostat.

The following are the basic characteristics of any system:

• Systems consist of interrelated components (a relationship exists between parts and the whole).
  
• Systems are arranged in a hierarchy (subsystems and suprasystems).
  
• Synergies among system components create a whole that is more than the sum of its parts.
  
• System boundaries are artificial: systems are components of another larger system. Systems can be open (influenced by their environment) or closed (not influenced by their environment).
  
• Systems have inputs, processes, outputs, and feedback loops.
  
• The process of homeostasis acts to bring a system back to equilibrium when it is disturbed by external forces.
  
• Unless energy is continually focused on this activity, the process of entropy causes energy within a system to dissipate and become random.
  

Also see:

• Examples from different kinds of systems
  
• How do you transform education through systemic change?
  

Last Modified: 07 November 1999
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