How Strong Is a Counterfactual?

The literature on counterfactuals is dominated by strict accounts (SA) and variably (VSA). Counterexamples to the principle of Antecedent Strengthening were thought be fatal SA; but it has been shown that adding dynamic resources view, such examples can accounted for. We broaden debate between VSA SA focusing a new strengthening principle, with Possibility. show classically validates this principle. give counterexample extra cannot help SA. then for if allows orderings worlds are not almost-connected, an ordering naturally falls out Kratzerian source semantics. conclude failure Possibility tells strongly against Dynamic in favor source-based version VSA.