  The second and more famous argument makes use of the conclusion defended earlier that reason alone cannot move us to act. As we have seen, reason alone “can never immediately prevent or produce any action by contradicting or approving of it” (T 458). Morality — this argument goes on — influences our passions and actions: we are often impelled to or deterred from action by our opinions of obligation or injustice. Therefore morals cannot be derived from reason alone. This argument is first introduced as showing it impossible “from reason alone... to distinguish betwixt moral good and evil” (T 457) — that is, it is billed as establishing the epistemic thesis. But Hume also says that, like the little direct argument above, it proves that “actions do not derive their merit from a conformity to reason, nor their blame from a contrariety to it” (T458): it is not the reasonableness of an action that makes it good, or its unreasonableness that makes it evil.