Modal scope fallacy
The condition b) is a statement of fact about John which makes him subject to a); that is, b) declares John a bachelor, and a) states that all bachelors are unmarried.John, of course, is always free to stop being a bachelor, simply by getting married; if he does so, b) is no longer true and thus not subject to the tautology a).In this case, c) has unwarranted necessity by assuming, incorrectly, that John cannot stop being a bachelor.Formally speaking, this type of argument equivocates between the de dicto necessity of a) and the de re necessity of c).[1] Using the formal symbolism in modal logic, the de dicto expression