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: If Charles were a writer, then James is a politician. For all x, x will sleep or x is a writer. Charles is sleeping if and only if James is a politician.
If Charles sleeps, then James is a politician can be inferred via the biconditional elimination rule. If James were a politician, then Charles is sleeping can be inferred via the biconditional elimination rule.