Consider the following premises. U(j_1). forall z_4: W(z_4) <-> U(z_4). Can we infer W(j_1) from them?
 From forall z_4: W(z_4) <-> U(z_4) we can infer W(j_1) <-> U(j_1). From W(j_1) <-> U(j_1) we can infer U(j_1) -> W(j_1). Finally, from U(j_1) -> W(j_1), U(j_1) we can infer W(j_1). Therefore, the answer is yes.