 (We have simplified Tarski’s presentation somewhat.) This is an adequacy condition for theories, not a theory itself. Given the assumption that \(\mathbf{L}\) is fully interpreted, we may assume that each sentence \(\phi\) in fact has a truth value. In light of this, Convention T guarantees that the truth predicate given by the theory will be extensionally correct, i.e., have as its extension all and only the true sentences of \(\mathbf{L}\).