What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one y for which if y cooks, then y is a poet. For all y, if y cooks, then y is a poet. For all y, if y were a poet, then y is cooking.
For all y, y will cook if and only if y is a poet. For all y, y is a poet if and only if y will cook. There is at least one y for which y will cook if and only if y is a poet. There is at least one y for which y is a poet if and only if y will cook.