Brian C. Williams
The ability to reason about a series of complex events over time is essential in analyzing physical systems. This paper discusses the role of continuity in qualitative physics and its application in a system for analyzing the behavior of Digital MOS circuits that exhibit analog behavior. The discussion begins with a brief overview of the reasoning steps necessary to perform a qualitative simulation using Temporal Qualitative (TQ) Analysis. The discussion then focuses in on the use of continuity and the relationship between quantities and their higher order derivatives in describing how physical quantities change over time.