 Here is another reason for thinking that generalizations like \(\beta\) must be proved. A theory of the meaning of ‘true’ should explain our acceptance of propositions like \(\beta\), which, as Gupta (1993a) and Hill (2002) emphasize, should be knowable a priori by anyone who possesses the concept of truth (and who grasps the relevant logical concepts). But if such a proposition can be known a priori on the basis of a grasp of the concept of truth (and of the relevant logical concepts), then a theory that purports to specify the meaning of ‘true’ should be able to explain our acceptance of that proposition. But if an account of the meaning of ‘true’ is going to do this, it must be possible to derive the proposition from one or more of the clauses that constitute our grasp of the concept of truth.