Consider the following premises. forall y: ~T(y). forall y: T(y) -> U_1(y). exists y: R_2(y) -> U_1(y). forall y: U_1(y) <-> T(y). Can we infer forall y: R_2(y) from them?
 From forall y: U_1(y) <-> T(y) we can infer forall y: U_1(y) -> T(y). From forall y: U_1(y) -> T(y), forall y: T(y) -> U_1(y) we can infer forall y: U_1(y) <-> T(y). From forall y: U_1(y) <-> T(y), forall y: ~T(y) we can infer forall y: ~U_1(y). Finally, from exists y: R_2(y) -> U_1(y), forall y: ~U_1(y) we can infer exists y: ~R_2(y), which contradicts forall y: R_2(y). Therefore, the answer is no.