Consider the following premises. For all x_6, if x_6 takes a plane, then x_6 is an astronaut. For all x_6, x_6 is not a doctor. There is at least one x_6 for which if x_6 sleeps, then x_6 is taking a plane. For all x_6, if x_6 were an astronaut, then x_6 is a doctor. Can we infer the following from them? There is at least one x_6 for which x_6 will not sleep.
 From the fact that there is at least one x_6 for which if x_6 sleeps, then x_6 is taking a plane, and that for all x_6, if x_6 takes a plane, then x_6 is an astronaut we can infer that there is at least one x_6 for which if x_6 sleeps, then x_6 is an astronaut. From the fact that there is at least one x_6 for which if x_6 sleeps, then x_6 is an astronaut, and that for all x_6, if x_6 were an astronaut, then x_6 is a doctor we can infer that there is at least one x_6 for which if x_6 sleeps, then x_6 is a doctor. Finally, from the fact that there is at least one x_6 for which if x_6 sleeps, then x_6 is a doctor, and that for all x_6, x_6 is not a doctor we can infer that there is at least one x_6 for which x_6 will not sleep. Therefore, the answer is yes.