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 it rains, then John is a poet. If John were a poet, then it is raining. If John were a poet, then it is raining.
It is raining if and only if John is a poet can be inferred via the biconditional introduction rule. It is raining if and only if John is a poet can be inferred via the biconditional introduction rule. John is a poet if and only if it is raining can be inferred via the biconditional introduction rule. John is a poet if and only if it is raining can be inferred via the biconditional introduction rule.