Consider the following premises. For all x, x will sleep or x is not a poet. For all x, x is a poet or x will not sleep. For all x, x will not sleep. Can we infer the following from them? For all x, x is not a poet.
 From the fact that for all x, x will sleep or x is not a poet we can infer that for all x, if x were a poet, then x is sleeping. From the fact that for all x, x is a poet or x will not sleep we can infer that for all x, if x sleeps, then x is a poet. From the fact that for all x, if x were a poet, then x is sleeping, and that for all x, if x sleeps, then x is a poet we can infer that for all x, x is a poet if and only if x will sleep. Finally, from the fact that for all x, x is a poet if and only if x will sleep, and that for all x, x will not sleep we can infer that for all x, x is not a poet. Therefore, the answer is yes.