Consider the following premises. For all x_6, x_6 is a scientist if and only if x_6 will go running. For all x_6, x_6 is not a scientist. There is at least one x_6 for which if x_6 sleeps, then x_6 is running. For all x_6, if x_6 goes running, then x_6 is sleeping. 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 for all x_6, if x_6 goes running, then x_6 is sleeping, and that there is at least one x_6 for which if x_6 sleeps, then x_6 is running we can infer that there is at least one x_6 for which x_6 will go running if and only if x_6 will sleep. From the fact that for all x_6, x_6 is a scientist if and only if x_6 will go running, and that for all x_6, x_6 is not a scientist we can infer that for all x_6, x_6 will not go running. Finally, from the fact that there is at least one x_6 for which x_6 will go running if and only if x_6 will sleep, and that for all x_6, x_6 will not go running we can infer that there is at least one x_6 for which x_6 will not sleep. Therefore, the answer is yes.