Full Idea
A counterfactual is an invitation to consider what the properties picked out by the antecedent are powers for (where Lewis 1973 took it to be an invitation to consider what goes on in a selected possible world).
Gist of Idea
Counterfactuals invite us to consider the powers picked out by the antecedent
Source
Jonathan D. Jacobs (A Powers Theory of Modality [2010], §4.4.3)
Book Reference
-: 'Philosophical Studies' [-], p.19
A Reaction
A beautifully simple proposal from Jacobs, with which I agree. This seems to be an expansion of the Ramsey test for conditionals, where you consider the antecedent being true, and see what follows. What, we ask Ramsey, would make it follow?