  This counterexample can be resisted. For while it is possible that a fair coin lands only heads when tossed infinitely many times, it may not be that this all heads outcome sequence is a suitable sequence. For if we consider the counterfactual involved in RCT—what would happen, if a fair coin were tossed infinitely many times—we would say: it would land heads about half the time. That is (on the standard, though not uncontroversial, Lewis-Stalnaker semantics for counterfactuals: Lewis 1973), though the all-heads outcome sequence is possible, it does not occur at any of the nearest possibilities in which a fair coin is tossed infinitely many times.