Consider the following premises. forall x: T(x) <-> S(x). Can we infer T(i) -> S(i) from them?
 From forall x: T(x) <-> S(x) we can infer T(i) <-> S(i). Finally, from T(i) <-> S(i) we can infer T(i) -> S(i). Therefore, the answer is yes.