  We would in this case have to use a metalanguage with a stronger logic, one that provides rules for manipulating “large satisfier of \(\phi\) on \(a\).” (As Evans notes, all we would really need in order to derive T-sentences would be a rule licensing the derivation of \(\cq{\tau \text{ is a large satisfier of } \phi \text{ on } a}\) from \(\cq{\phi \equiv \psi}\) and \(\cq{\tau \text{ is a larger satisfier of } \psi \text{ on } a}\).) But such a metalanguage cannot be ruled out without begging the question about the logicality of “large.”