  Suppose Jop and Dop are college students who are dating. They disagree about two matters: whether it’s harder to get top grades in economics classes or philosophy classes, and whether they should move in together this summer. The first disagreement is over the truth of a claim: is the claim (or belief) ‘It is harder to get top grades in economics classes compared to philosophy classes’ true or not? The second disagreement is over an action: should we move in together or not (the action = moving in together)? Call the first kind of disagreement belief-disagreement; call the second kind action-disagreement.