Peter Checkland, a British professor in systems science, published his book Systems Thinking Systems Practice in 1981. With this book he joins the scientists who have launched natural systems hierarchies, in his case called the Systems Typology. According to Checkland, the absolute minimum number of systems classes necessary to describe the existing reality is four. They are natural, human activity, designed physical, designed abstract, systems. (The typological map itself belongs to designed abstract systems.) Natural systems provide the possibility to investigate, describe and learn; human activity systems can be engineered and the designed systems can be created and employed.
Starting with natural systems, Checkland claims that ‘they are systems which could not be other than they are, given a universe whose patterns and laws are not erratic.’ Their origin is the origin of the universe and the processes of evolution. Within the natural systems there exists an obvious hierarchy from atoms to molecules. Combinations of molecules then give rise to a branched hierarchy.
The next main level to be considered is that of human activity systems (HAS) which have a tendency to integrate in such a way that they can be viewed as a whole. Most often other (designed) systems are coupled to them. An example is the oil industry with its oil rigs, tankers and fine meshed distribution system. Out of the enormous number of human activity systems a few of the most typical can be noted.
Figure 3.20 A typology map of systems.
- agricultural
- defence
- trading
- transportation
However, most fundamental on this level is the social system, represented by family, tribe, clan, etc. Typical here is the basic need of the members for mutual support within the frame of a community. In a sense, with their central structure, social systems belong to both natural and human activity systems. They have therefore been placed on the boundary between the two categories in the typology map of systems in Figure 3.19.
Designed physical systems can be defined as systems fitted with purpose of mind because a need for them in some human activity has been identified. To this category belong:
- individual tools
- individual machines
- other designed and fabricated material entities
Designed abstract systems are various types of theological, philosophical or knowledge systems. While designed physical systems in principle can be produced by animals and insects (the bird’s nest, the spider’s web, the beaver’s dam), designed abstract systems are only associated with human beings.
In Figure 3.20, all systems are related to each other on a global map. The difference in logic types between natural and human activity systems gives rise to separate kinds of investigations. The classical method of science with its observer standing outside is quite relevant for natural systems. When it comes to human activity systems, Checkland emphasizes the importance of the point of view influencing the observations.
Source: Skyttner Lars (2006), General Systems Theory: Problems, Perspectives, Practice, Wspc, 2nd Edition.