 Carnap’s relaxed attitude stems from his abandonment of the search for epistemological foundations. If one hopes to secure our knowledge of mathematics by appeal to a formalist interpretation then the search for a consistency proof of the type Hilbert sought makes sense and one will look for a vindication of mathematics as a whole from within a limited fragment with respect to which our knowledge seems hard to impugn. But Carnap, perhaps as a result of Gödel’s deep theorems, seems to have abandoned that goal and thought that the Principle of Tolerance absolved him of any such need. One can stipulate what one likes, including stronger axiom systems from which one can prove the consistency of a weaker theory. This does not give any firmer grounds for believing or accepting the weaker theory, but one does not need such grounds anyway.