Abstract
Harry Frankfurt has famously argued against the principle of alternate possibilities by presenting a case in which, apparently, a person is morally responsible for what he has done even though he could not have done otherwise. A number of commentators have proposed dispositionalist responses to Frankfurt, arguing that he has not produced a counterexample to PAP because, contrary to appearances, the ability to do otherwise is indeed present but is a disposition that has been ‘masked’ or ‘finked’ by the presence of a counterfactual controller. This article argues that this response to Frankfurt does not undercut his attack on PAP, since there are Frankfurt-style counterexamples to the principle—‘brain-malfunction’ cases—that evade the dispositionalist analysis.