What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: Joseph is not a politician. For all x_8, if x_8 were a politician, then x_8 is reading a book. Joseph is reading a book or it is raining. For all x_8, if x_8 reads a book, then x_8 is a politician.
For all x_8, x_8 is a politician if and only if x_8 will read a book can be inferred via the universal biconditional introduction rule. For all x_8, x_8 will read a book if and only if x_8 is a politician can be inferred via the universal biconditional introduction rule.