Causality in Device Behavior

This paper shows how formal characterizations of causality and of the method of comparative statics, long used in economics, thermodynamics and other domains, can be applied to clarify and make rigorous the qualitative causal calculus recently proposed by de Kleer and Brown (1984). The formalization shows exactly what assumptions are required to carry out causal analysis of a system of interdependent variables in equilibrium and to propagate disturbances through such a system. Causality 3 April 1985 List of F igures F igure 1: Evaporator 4 F igure 2: Matrix of Structural Equations for Evaporator 8 F igure 3: Causal Structure for Evaporator 8 F igure 4: Alternative Causal Structure for Evaporator 13 F igure 5: Simple Conduit 20 F igure 6: Pressure Regulator 22