Causation and Causal Factuals

Abstract

Martin Bunzl in a recent article, 'Causal Factuals', attempts to adapt and improve upon an approach to causation associated with the counterfactual theory of causation.1 The best known counterfactual theory, that proposed by David Lewis, analyses singular causal state? ments in terms of counterfactuals, and analyses the latter by way of possible world semantics.2 Bunzl proposes to short-circuit this strategy by moving directly from causation to a possible world semantics very much like that given for counterfactuals by Lewis. Any claimed advantage is to be gained by dropping Lewis' requirement that the relevant possible worlds which appear in the analysis satisfy some condition of comparative overall similarity. This condition, which is central to Lewis' theory of counterfactuals, has generated severe difficulties with respect to the task of stating truth conditions for causal statements. In this paper I will argue that Bunzl's analysis is subject to problem cases which bear a close resemblance to those which plague counterfactual theory. The counterfactual theory of causation has it that c causes e if and only if had c not occurred then e would not have occurred. This counterfactual is analysed using possible worlds. Roughly, in worlds as much like the actual world as possible, except that c does not occur, e does not occur. Comparative similarity of worlds is determined by way of similarity of fact and law. According to Bunzl the counterfactual theorist would like to hold that the closest possible worlds are those in which the following principle reigns, a principle which is central to our causal intuitions: all the facts are the same up to the point of the occurrence of the alledged cause c and the only law violations are those necessary at that point just to prevent c from occurring, e does not occur in such worlds just in case c is a cause of e in the actual world. As Bunzl says "the task confronting counterfactual theorists is to show how such an outcome is the outcome that occurs under circumstances that