Consider the following premises. For all x_15, if x_15 cooks, then x_15 is sleeping. For all x_15, x_15 will cook if and only if x_15 is an artist. There is at least one x_15 for which x_15 is an artist if and only if x_15 will sleep. Can we infer the following from them? There is at least one x_15 for which if x_15 were an artist, then x_15 is sleeping.
 From the fact that for all x_15, x_15 will cook if and only if x_15 is an artist we can infer that for all x_15, if x_15 were an artist, then x_15 is cooking. From the fact that for all x_15, if x_15 were an artist, then x_15 is cooking, and that for all x_15, if x_15 cooks, then x_15 is sleeping we can infer that for all x_15, if x_15 were an artist, then x_15 is sleeping. From the fact that there is at least one x_15 for which x_15 is an artist if and only if x_15 will sleep we can infer that there is at least one x_15 for which if x_15 sleeps, then x_15 is an artist. From the fact that for all x_15, if x_15 were an artist, then x_15 is sleeping, and that there is at least one x_15 for which if x_15 sleeps, then x_15 is an artist we can infer that there is at least one x_15 for which x_15 is an artist if and only if x_15 will sleep. Finally, from the fact that there is at least one x_15 for which x_15 is an artist if and only if x_15 will sleep we can infer that there is at least one x_15 for which if x_15 were an artist, then x_15 is sleeping. Therefore, the answer is yes.