Consider the following premises. For all z, if z drinks water, then z is a soldier. For all z, z is not a soldier. There is at least one z for which z will drink water. Can we infer the following from them? There is at least one z for which z is a scientist.
 From the fact that for all z, if z drinks water, then z is a soldier, and that for all z, z is not a soldier we can infer that for all z, z will not drink water. From the fact that there is at least one z for which z will drink water we can infer that there is at least one z for which z will drink water or z is a scientist. Finally, from the fact that there is at least one z for which z will drink water or z is a scientist, and that for all z, z will not drink water we can infer that there is at least one z for which z is a scientist. Therefore, the answer is yes. Notice, however, that the premises were contradictory, so we can infer anything from them.