There are multiple ways of characterizing systems. Of those I have come to understand to date, several of the most useful are as follows.
Ackoff Classification of Systems
- Mechanistic System: Where the whole has no purposes of its own and the parts have no purposes of their own. Example: car engine, where neither the parts nor the whole can autonomously decide to have different ends or different means.
- Animated System: Where the whole has purposes of its own but the parts do not. Example: human body, where the whole of a person can have purposes of her/his own, but the parts cannot (heart cannot autonomously decide to do the work of the liver).
- Social System: Where the whole has purposes of its own as well as the parts. Example: business enterprise, where the organization has purposes of its own and the people working there maintain purposes of their own.
- Ecological System: Where the parts have purposes of their own, but the whole does not. Example: Planet earth, where people have purposes of their own but the planet itself does not.
Reference: Types of Systems Ackoff Collaboratory
Boulding's Hierarchy of Systems
Economist Kenneth Boulding, (1985) one of the founders of The Society for General Systems Theory, defined 5 generalized classes of systems which encompasses all other systems. These provide a means of understanding some general characteristics of systems. These systems are arranged in what is considered an evolutionary hierarchy.
- This is a system in which a positive influence from one element to another provides a negative influence in return to the first element.
- "I get positive things from you and provide you a negative return in response. Essentially I subsist on you."
- In this type of system the elements are essentially dependent on each other from the perspective that the quantity of one element determines the quantity of the other element. The Foxes/Rabbits example is a prey/predator system. Even though the fox may be detrimental to the continuation of an individual rabbit, the fox is instrumental in maintaining the health of the overall rabbit population.
- "I will feed upon you even though my existence is dependent upon your existence."
- A threat system is one in which one element doesn't do something if the other element doesn't do something else. The U.S./Soviet Arms Race was a specific example. This particular example lead to escalation since each side said to the other, "If you start a war I will destroy you." Yet to continue to validate the threat each side had to continue building arms. It has been said this is a fine example of two countries racing headlong to where neither of them wanted to be.
- "If you don't do something I don't want you to do then I won't do something you don't want me to do". This may also be formed as: "If you do something I want you to do, then I won't do something you don't want me to".
- The capitalist economy is a very good example of an exchange system. Elements of the system provide goods and services to other elements in exchange for money or other goods and services.
- "If you do something I want you to do, then I will do something you want me to do." This may also be stated as: "If I do something you want me to do then I expect you will do something I want you to do."
- Our buy now pay later economy has a tendency to change an exchange system into a threat system. Initially we purchase something and in exchange we provide a promise, a promise to pay more later. Once we have received what we wanted the system changes and the bank says: "If you pay your bills then I won't take the stuff away from you", which is essentially a threat system.
- Employer/Employee systems are often transformed from exchange systems to a threat system. The employee is hired under an exchange premise: "I will pay you (what you want) if you do this work (what I want)". Once the employee is hired the situation changes and becomes: "If you do what I want I won't fire you".
- Examples of an integrative system are charitable organizations or business endeavors where individuals ban together to accomplish some common desired objective or goal.
- "Where you and I do something together because of what we both want to accomplish."
- The greatest leverage is found in integrative systems, where all the individuals are motivated by what they are endeavoring to create.
- During discussions on the Learning Organization list sometime in late 1995 Michael McMaster proposed another category beyond the Integrative System. Michael proposed what he called the Generative System, which might be represented by a situation where two or more people come together and create something neither of them had any idea of when they began.
Gharajedaghi Classification of Systems
Jamshid Gharajedaghi classified systems as:
- Mechanistic systems, that are mindless, they have no purpose of their own except to create profit for their owners.
- Biological systems that are uniminded with a purpose of their own, dictated by an executive and although the system has a choice the parts don’t
- Sociocultural system that is multiminded, with a choice of ends and mean. The parts share values and work by consensus.
Isolated, Open and Closed Systems
Systems may be characterized as either closed or open. A closed system is one that does not need to interact with its environment to maintain its existence. Examples are atoms and molecules. Mechanical systems are closed systems. Open systems are organic and must interact with their environment in order to maintain their existence. People are open systems in that they must interact with their environment in order to take in food, water, and obtain shelter. People provide waste products to the environment in return.
The examples of the furnace, filling the water glass, adjusting the shower tap are all open systems as there are elements outside the system which are considered to have an effect yet are not elaborated.
An open system may interact with its environment in a growth or balancing fashion. Often the time of influence of the open system on the environment or the environment on the system may be of such lengthy duration or of such minimal nature as to limit its need to be considered. In 1927 Ludwig von Bertalanffy first proposed that the human organism should be treated as an open system.
Any system taken in a large enough context can be considered a closed system. It is often more appropriate to consider a system as a subsystem of some larger system with which it must interact in some way. Taking the larger system into account is unnecessary for understanding the operation of the subsystem. All systems are both subsystems of larger systems and composed of subsystems at the same time.
The Systems Archetypes are a classification of systems into a set structure with unique patterns of behavior which recur across all disciplines of science.
At one time I happened across another definition of a systems hierarchy which seemed to make a lot of sense, yet at present I can't recall the reference from whence it came. If you know please send me a note.
Protection System - act when events occur (reactive)
Regulating System - single loop - continuously measure or sample control variables and compare with pre-set desired values and adjust accordingly to regulate control variables (responsive)
Optimizing System - double loop - regulates selected variables in accordance with desired values and also ascertains what the desired values should be to satisfy pre-determined goals (systemic)
Adaptive System - multi-loop/structural - system changes its internal structure in order to optimize its behavior in spite of continuous changes in the environment... (evolutionary)
- Motivation: Doing it to Each Other or Doing it to Ourselves
- Ackoff, Russell (1971) Towards a Systems of Systems Concepts
- Lewis, Gaye (2002) Systems Thinking About Purpose
- On The Mismatch Between Systems and Their Models by Russell L. Ackoff and Jamshid Gharajedaghi
- The Cynefin Framework a video with Dave Snowden
- Profiling Complex Systems by Renee Stevens
Systems Thinking World Discussions * Gene Bellinger