10 Qualitative Simulation and Reasoning about Change

The concept of qualitative simulation is central to qualitative reasoning, so it is worth considering its properties in more detail. Some of these properties have been extensively worked out and proven formally to apply to any theory of qualitative dynamics. Others are based more on experience with qualitative simulation techniques applied to a variety of problems and domains. We begin by summarizing the basic ideas, bringing together concepts introduced in chapters 5, 6, and 7. Then we discuss how existence and continuity interact with reasoning about change. Finally, we discuss some formal properties of qualitative simulation, ending with an open question.