Consider the following premises. U(c_1) -> R_4(c_1). forall x_1: R_4(x_1) <-> U(x_1). Can we infer R_4(c_1) -> U(c_1) from them?
 From forall x_1: R_4(x_1) <-> U(x_1) we can infer R_4(c_1) <-> U(c_1). Finally, from R_4(c_1) <-> U(c_1) we can infer R_4(c_1) -> U(c_1). Therefore, the answer is yes.