Causality and Dispersion: A Reply to John Norton

Classical dispersion relations are derived from a time-asymmetric constraint. I argue that the standard causal interpretation of this constraint plays a scientifically legitimate role in dispersion theory, and hence provides a counterexample to the causal skepticism advanced by John Norton and others. Norton ([2009]) argues that the causal interpretation of the time-asymmetric constraint is an empty honorific and that the constraint can be motivated by purely non-causal considerations. In this paper I respond to Norton’s criticisms and argue that Norton’s skepticism derives its force partly by holding causal principles to a standard too high to be met by other scientifically legitimate constraints.