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