Consider the following premises. forall x_12: P_12(x_12) <-> Q_12(x_12). R_6(i) -> u_4. forall x_12: Q_12(x_12) -> R_6(x_12). Can we infer P_12(i) from them? If possible, name the inference rules being used at each step.
We cannot infer that from the premises. Therefore the answer is no.