Is anyone familiar with an old paper of C.C. Chang entitled "The Axiom of Comprehension in Infinite-Valued Logic" which shows that the Axiom of Comprehension without parameters is consistent in the infinite-valued logic of Lukasiewicz and a newer paper by Richard White ("The Consistency of the Axiom of Comprehension in the Infinite-Valued Predicate Logic of Lukasiewicz") in which he shows that the full Axiom of Comprehension is consistent in the infinite-valued predicate logic of Lukasiewicz? I ask because I am interested if finding out if anyone has found a way construe this infinite-valued predicate logic of Lukasiewicz as a Boolean-valued model (or contrariwise, can the full Axiom of Comprehension be shown to be consistent in some Boolean-valued model)? If so, please provide for me the reference(s).

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Boolean-valued logic is still exactly the same classical logic as the two-valued one, no matter how large a Boolean algebra you take (which is the reason why forcing in ZFC using Boolean-valued models can work in the first place). The number of truth values as such is mostly irrelevant, what matters is what equations hold in the algebra of truth values. The comprehension axiom is inconsistent with classical logic, hence it cannot hold in any Boolean-valued model. – Emil Jeřábek Jan 23 '12 at 11:45