 To begin, it is important to first get clear on what type of moral responsibility is being doubted or denied by skeptics. Most moral responsibility skeptics maintain that our best philosophical and scientific theories about the world indicate that what we do and the way we are is ultimately the result of factors beyond our control, whether that be determinism, chance, or luck, and because of this agents are never morally responsible in the sense needed to justify certain kinds of desert-based judgments, attitudes, or treatments—such as resentment, indignation, moral anger, backward-looking blame, and retributive punishment. This is not to say that there are not other conceptions of responsibility that can be reconciled with determinism, chance, or luck. Nor is it to deny that there may be good reasons to maintain certain systems of punishment and reward. Rather, it is to insist that to hold people truly deserving of blame and praise, punishment and reward, would be to hold them responsible for the results of the morally arbitrary or for what is ultimately beyond their control, which is fundamentally unfair and unjust. Other skeptics defend the more moderate claim that in any particular case in which we may be tempted to judge that an agent is morally responsible in the desert-based sense, we lack the epistemic warrant to do so (e.g., Rosen 2004). 