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 James drinks water, then Mary is a poet. Mary is a poet if and only if James is drinking water. If Mary were a poet, then James is drinking water.
James is drinking water if and only if Mary is a poet can be inferred via the biconditional introduction rule. Mary is a poet if and only if James is drinking water can be inferred via the biconditional introduction rule. If Mary were a poet, then James is drinking water can be inferred via the biconditional elimination rule. If James drinks water, then Mary is a poet can be inferred via the biconditional elimination rule.