Translate the following inference to logic notation: There is at least one x for which z is not a poet. For all x, z is a poet or z is not an office clerk. For all x, z is an office clerk if and only if z is a poet. Therefore there is at least one x for which z is not an office clerk.
exists x: ~P(x). forall x: P(x) or ~Q(x). forall x: Q(x) <-> P(x). Therefore exists x: ~Q(x).