Consider the following premises. forall x_10: R_10(x_10) -> S_10(x_10). s -> R_10(a_10). S_10(a_10) -> s. Can we infer s <-> S_10(a_10) from them?
 From forall x_10: R_10(x_10) -> S_10(x_10) we can infer R_10(a_10) -> S_10(a_10). From s -> R_10(a_10), R_10(a_10) -> S_10(a_10) we can infer s -> S_10(a_10). Finally, from s -> S_10(a_10), S_10(a_10) -> s we can infer s <-> S_10(a_10). Therefore, the answer is yes.