Object-Oriented Conceptual Graphs

In this paper a state based view of conceptual graphs borrowed from the Object-Z program specification language is introduced. This new view is contrasted with the object-oriented model developed by Sowa [5]. The new model is demonstrated by reducing Sowa's example proof from 18 steps to 4 steps. The new model uses relations connecting object pre-states and post-states to represent object methods, rather than using messages as concepts as in Sowa's version. We argue that the new model is clearer because it is based on a simple state transition and that this leads to more efficient theorem proving and programming.