Abstract:
The central component of commonsense reasoning about causality is the envisionment: a description of the behavior of a physical system that is derived from its structural description by qualitative simulation. Two problems with creating the envisionment are the qualitative representation of quantity and the detection of previously-unsuspected points of qualitative change. The representation presented here has the expressive power of differential equations, and the qualitative envisionment strategy needed for commonsense knowledge. A detailed example shows how it is able to detect a previously unsuspected point at which the system is in stable equilibrium.