AECT Council on Systemic Change

Characteristics of a System

What is a System?

The Hierarchy of Systems

Our understanding of how systems work must begin with a basic idea of what a system is.  We use the word in everyday conversations, in phrases like "nervous system," "legal system," "school system," or even "cooling system."  Simply put, a system is a collection of parts that interact with each other to function as a whole.

In general, any given system is composed of other systems of about the same level, which together comprise the larger system. Thus, a particular protein molecule might contain atoms of carbon, hydrogen, oxygen, and nitrogen; an economy is made up of people, land, buildings, machines, plants, dairy herds, and so on; the solar system is made up of the sun, the planets and their moons, and many, many asteroids, comets, and other bits of debris. If we had started at a different point, for example, an atom in a cow's brain, the list would have looked a little different in the middle, but it would still consist of a similar set of steps, with smaller systems combining to make larger systems that combine with others to make still larger systems (Kauffman, 1978).

Can One System be a "Piece" of Another System?

YES!  We have seen that systems are composed of interrelated parts.  When one of these parts is itself a system (i.e., that part consists of two or more interrelated parts), we call the smaller system a subsystem and the larger system its suprasystem.  And that larger system, of course, can be a subsystem of a still larger system.

For example, have you seen a systemic cow?

Also see:

Last Modified: 07 November 1999
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