A system is a whole that is defined by its function in a larger system of which it is a part. – Ackoff, Russell. Differences That Make a Difference: An Annotated Glossary of Distinctions Important in Management (p. 119). Triarchy Press. Kindle Edition.
A system is a whole consisting of two or more parts that satisfies the following five conditions:
- The whole has one or more defining properties or functions
- Each part in the set can affect the behavior or properties of the whole
- There is a subset of parts that is sufficient in one or more environments for carrying out the defining function of the whole; each of these parts is necessary but insufficient for carrying out this defining function.
- The way that each essential part of a system affects its behavior or properties depends on (the behavior or properties of) at least one other essential part of the system.
- The effect of any subset of essential parts on the system as a whole depends on the behavior of at least one other such subset.”
– Ackoff, Russell L. Re-creating the corporation : a design of organizations for the 21st century. New York: Oxford University Press, 1999.
“Summarizing and oversimplifying: A system is a whole that cannot be divided into independent parts without loss of its essential properties or functions.” – Ackoff, Russell L. Re-creating the corporation : a design of organizations for the 21st century. New York: Oxford University Press, 1999.