Consider the following premises. forall x_16: U(x_16) -> S_16(x_16). S_16(i) -> U(i). ~S_16(i). Can we infer ~U(i) or w from them?
 From forall x_16: U(x_16) -> S_16(x_16) we can infer U(i) -> S_16(i). From S_16(i) -> U(i), U(i) -> S_16(i) we can infer S_16(i) <-> U(i). From S_16(i) <-> U(i), ~S_16(i) we can infer ~U(i). Finally, from ~U(i) we can infer ~U(i) or w. Therefore, the answer is yes.