Consider the following premises. For all x_8, x_8 will play tennis if and only if x_8 is a doctor. For all x_8, if x_8 were a doctor, then x_8 is listening to a song. For all x_8, if x_8 listens to a song, then x_8 is playing tennis. For all x_8, x_8 will not listen to a song. Can we infer the following from them? There is at least one x_8 for which x_8 is a doctor.
 From the fact that for all x_8, x_8 will play tennis if and only if x_8 is a doctor we can infer that for all x_8, if x_8 plays tennis, then x_8 is a doctor. From the fact that for all x_8, if x_8 listens to a song, then x_8 is playing tennis, and that for all x_8, if x_8 plays tennis, then x_8 is a doctor we can infer that for all x_8, if x_8 listens to a song, then x_8 is a doctor. From the fact that for all x_8, if x_8 were a doctor, then x_8 is listening to a song, and that for all x_8, if x_8 listens to a song, then x_8 is a doctor we can infer that for all x_8, x_8 is a doctor if and only if x_8 will listen to a song. Finally, from the fact that for all x_8, x_8 is a doctor if and only if x_8 will listen to a song, and that for all x_8, x_8 will not listen to a song we can infer that for all x_8, x_8 is not a doctor, which contradicts that There is at least one x_8 for which x_8 is a doctor. Therefore, the answer is no.