 Fischer’s reasons-responsiveness compatibilist starts by rejecting the key premise of the Classical Incompatibilist Argument, in that it rejects the thesis that freedom of the sort required for moral responsibility requires the ability to do otherwise. But how does Fischer’s view stack up against the Source Incompatibilist Argument? The challenge Fischer faces here, which is pushed forcefully by Pereboom (2001) and Mele (2019), is the same as that faced by Frankfurt and Wolf. The source incompatibilist maintains that it is a necessary condition of free will that one be an ultimate source of her action, and determinism is incompatible with one’s being an ultimate source of her action. The compatibilist’s task is to show that her treatment of the source of an agent’s conduct is sufficient for free will. But the source incompatibilist will point to manipulation cases that suggest that some causal histories giving rise to compatibilist-friendly psychological structures, such as reasons-responsive mechanisms, are freedom and responsibility undermining. If so, then why is determinism any different from a manipulation case? The burden, it seems, is on the compatibilist to show how it is that manipulation cases differ from a normal deterministic history. The compatibilist’s only other strategy is simply to deny that the pertinent manipulated agents are not free and morally responsible. This problem is not lost on reasons-responsiveness compatibilists, of course (see Fischer 2004 for one attempt to address these issues).