Counterfactuals, Accessibility, and Comparative Similarity

Berit Brogaard and Joe Salerno (2008) have defended the validity of counterfactual hypothetical syllogism (CHS) within the Stalnaker-Lewis account. Whenever the premisses of an instance of CHS are non-vacuosly true, a shift in context has occurred. Hence the standard counterexamples to CHS suffer from context failure. Charles Cross (2011) rejects this argument as irreconcilable with the Stalnaker-Lewis account. I argue against Cross that the basic Stalnaker-Lewis truth condition may be supplemented in a way that makes (CHS) valid. Yet pace Brogaard and Salerno, there are alternative ways of spelling out the basic truth condition which are standard in most debates; and given these ways, the counterexamples to CHS are successful. Charles Cross (2011) has taken issue with Berit Brogaard and Joe Salerno’s argument for the validity of counterfactual hypothetical syllogism (CHS). The classical example: (Hoover) [H1] If J. Edgar Hoover had been a communist, he would have been a traitor. [H2] If he had been born a Russian, he would have been a communist. [H3] Therefore, if he had been born a Russian, he would have been a traitor.(Brogaard and Salerno 2008: 39) Brogaard and Salerno argue for the following claim: 1 I am very grateful to Professor Cross for intense discussion.