What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_10, x_10 will write a letter. There is at least one x_10 for which if x_10 were a poet, then x_10 is not writing a letter. For all x_10, x_10 is a poet. For all x_10, x_10 is an astronaut.
Since the premises are contradictory, we can infer anything from them.