 It appears not, for this replacement looks vulnerable to many of the same arguments  (§3).  But to test this alleged symmetry, focus in particular on whether an FSC can be constructed as a counterexample to PAP-omissions (van Inwagen 1978, 204–5): Bob sees a man being robbed and beaten outside of his house. After considering whether to call the police, Bob decides not to get involved, calculating that it wouldn’t be worth the trouble. For his own reasons, then, Bob refrains from calling the police. What Bob didn’t know, however, is that the due to a technology disaster, all of the phones in the city are out of order and will be for hours. It seems then that Bob isn’t responsible for failing to call the police. And plausibly, PAP-omissions explains why he’s off the hook: due to the telephone disaster, he could not have called the police. (He might still be responsible for failing to try to call the police, but trying is something he could have done.) Given the present assumption that PAP is false, what emerges from such examples is, contrary to initial appearances, an important asymmetry: 