Invariance Applied

This chapter applies the ideas about invariance from Chapter 5 to the analysis (both normative and descriptive) of various aspects of commonsense cause reasoning. The focus is mainly on one particular kind of invariance—invariance under changes in background conditions, here called insensitivity. This is used to cast light on causal judgments involving omissions and examples involving double prevention (in which the occurrence of c prevents the occurrence of e, which had it occurred, would have prevented the occurrence of f, with the result that f occurs). It is argued that causal claims regarding omissions and double prevention relations differ normatively depending on the invariance of the relations involved and that this is also reflected in the judgments that people make about such claims.