Consider the following premises. exists x: W_4(x) -> T(x). forall x: ~W_4(x). forall x: W_4(x) <-> T(x). Can we infer forall x: T(x) from them? If possible, name the inference rules being used at each step.
 From forall x: W_4(x) <-> T(x) we can infer forall x: T(x) -> W_4(x) via universal biconditional elimination. From forall x: T(x) -> W_4(x), exists x: W_4(x) -> T(x) we can infer exists x: T(x) <-> W_4(x) via existential biconditional introduction. Finally, from exists x: T(x) <-> W_4(x), forall x: ~W_4(x) we can infer exists x: ~T(x) via existential biconditional elimination, which contradicts forall x: T(x). Therefore, the answer is no.