In order to minimize the variability of domain specific knowledge, the variables have phantasy names. As a consequence, only general prior knowledge, e.g. knowledge about causal relations, can be brought to bear in the problem solving process. 1 shows a simple example of such a system. The control of dynamic systems is a form of complex problem solving. Unlike many other problem solving tasks, the effects of the operators are not explained in the instructions.
Many authors assume, that controlling systems effectively requires structural knowledge.
The notion of structural knowledge comprises knowledge about the variables and their causal relationships. But the results concerning the relation between structural knowledge and control performance are inconsistent. It is obvious, that the construct of structural knowledge is too undifferentiated to account for the diversity of the results. As a step towards an integrative explanation of these results I want to suggest a theoretical distinction of three different types of knowledge which can be relevant for the control of dynamic systems. These may be stored either externally or in declarative memory.