   Re (2): The only potential problematic self-reference is in the sentence Tτ, the so-called truth teller, which says of itself that it is true. Informal reasoning suggests that the truth teller can consistently be assigned either classical truth value: if you assign it the value t then no paradox is produced, since the sentence now truly says of itself that it is true; and if you assign it the value f then no paradox is produced, since the sentence now falsely says of itself that it is true. Theorem 2.1 (2) formalizes this point, i.e., M2 can be expanded to one Tarskian model in which Tτ is true and one in which Tτ is false. The fact that M2 can be expanded to exactly two Tarskian models needs the Transfer Theorem, alluded to above. Note that the language L2, interpreted by either of these expansions, provides another example of an interpreted language that has its own truth predicate satisfying the T-biconditionals classically understood, obeys the rules of standard classical logic, and has the ability to refer to each of its own sentences. 