 Carnap (1963) was receptive to the adoption of an intensional methodology that went beyond the constraints of extensional logic, which Hempel (1965b) would consider but leave for others to pursue (Fetzer 1981, 1993). The distinction can be elaborated with respect to the difference between the actual world and alternative possible worlds as sequences of events that diverge from those that define the history of the actual world. If specific conditions that obtained at a specific time had been different, for example, the course of ensuing events would have changed. These intensional methods can be applied to the problems of defining dispositions and the nature of laws by employing descriptions of possible worlds as variations on the actual, not as alternatives that are “as real as” the actual—as David Lewis (2001a,b) has proposed—but as a means for formally specifying the semantic content of subjunctives and counterfactuals (where counterfactuals are subjunctives with false antecedents), using an alternative calculus.