Structure of Systems - Introduction


In this series of documents, we are concerned with the organisational structure, of systems, and with the way that such structures evolve. In the past, the representation of such structures has been too simplistic and hard to change, e.g. organisation charts or wiring diagrams. We need to do better.

We view any system, as being a component, in many larger composite systems, as well as being, itself, a composition, of smaller component systems. Clearly, composite systems can share components. Thus, systems exist in a huge, directed graph, with the system, represented by the bottom node, of each line, in the graph, being a component, of the system, represented by the top node. At the extremes, the top node, of the whole directed graph, represents the universe, and the bottom nodes represent microscopic systems (many, of which are, at present, beyond human decomposition, or even comprehension).

We see systems evolving, by means of movements, of component systems, between composite systems. The movements are driven, by interactions, between composite systems, and these interactions are supported, by systems, that connect the interacting composite systems. All, of the movements, are reflected, by changes to the directed graph.

The above is obviously taking an extremely broad view of systems. It is assuming, that any set, of systems, can form a composite system, even if these component systems are remote from each other, and never likely to interact. Thus, all systems, and all past and all future states or component structures, of systems, exist in the directed graph, described above.

In the real world, we must restrict our attention, to a sub-graph of the full directed graph. We could think of this sub-graph, as being illuminated, by a notional spotlight, with the spotlight-beam moving gradually, across the total graph. Alternatively, we could just think of this subgraph, as a graph, representing the systems, that are of interest to us. In a later document, we will describe our notation, for representing this graph and its gradual evolution.

We have produced a series, of documents, as listed below. The second document, describes our notation, supporting the view outlined above. The third and later documents give examples, of the use, of the notation, with the examples ranging, over systems, in various disciplines.

Long-Lived Systems

The systems that we represent, in our examples, are all reasonably long-lived. These systems seem to defy, the Second Law of Thermodynamics. That law says that the universe is evolving, towards a state, of maximum disorder or chaos. However, the organisation of the systems that we describe remain ordered, though changing, over lengthy periods. Physicists, and more recently business theorists, have explored this apparent contradiction. This exploration started in the mid nineteenth century:


Our background is in IT, so our main interest is in representing the structure, of IT systems and their interactions with human systems, business systems, and other systems. However, we thought it would be useful to explore the problem, of structural representation, across a range of disciplines. We hope that we have acquired adequate knowledge, of these disciplines, to make the examples, taken from them, useful, but we certainly do not claim any deep knowledge of the disciplines. The following is the list, of documents, that we have produced: