 Jeffrey used ratification as a means of making evidential decision theory yield the same recommendations as causal decision theory. In Newcomb’s problem, for instance, two-boxing is the only self-ratifying option. However, Jeffrey (2004: 113n) concedes that evidential decision theory’s reliance on ratification does not make it agree with causal decision theory in all cases. Moreover, Joyce (2007) argues that the motivation for ratification appeals to causal relations, so that even if it yields correct recommendations using Jeffrey’s formula for expected-utility, it still does not yield a purely evidential decision theory.