Defining characteristic of systems are:
- Systems have boundaries – they are distinguishable from their environment.
- Systems interact with their environment.
- Systems are composed by themselves of (Sub-)systems.
The Describe Anything (DA) method over-emphasizes these characteristics and provides a diagramming language which allow to create grossly simplified models – System Descriptions – of real world systems.
The DA simplifications are:
- System boundaries in DA are sharply defined. In contrast the boundaries of real world systems are blurry.
- The interaction of a DA System with its environment takes place via a finite set of single purpose Interfaces. Real world systems, on the other side, interact in very complex ways with each other, their interfaces multi-functional.
Interaction between DA Systems happens via Flows which are restricted to four fundamental types and one auxiliary type. The interaction over a specific Interface can only be of one of the following types:
- Actions – a variant of Information
In real world systems all of these types combine when interaction takes place.
- The environment – or Context – of DA Systems is a finite set of other DA Systems. Real world systems interact with the whole space-time continuum in manifold ways.
The simplifications of the Describe Anything method reflect the fact, that verbal reasoning can only ever embrace aspects of the real world, never The Whole in itself. On the other hand they focus and subordinate the collective creation of shared mental system models under the specific communication needs and relevant aspects of the goals of a community which uses DA.