Consider the following premises. For all x_15, x_15 will cook. For all x_15, if x_15 were a writer, then x_15 is not cooking. For all x_15, x_15 is a mechanic if and only if x_15 will sleep. For all x_15, if x_15 were a mechanic, then x_15 is sleeping. There is at least one x_15 for which if x_15 were a mechanic, then x_15 is a writer. Can we infer the following from them? For all x_15, x_15 will sleep.
 From the fact that for all x_15, if x_15 were a writer, then x_15 is not cooking, and that for all x_15, x_15 will cook we can infer that for all x_15, x_15 is not a writer. From the fact that there is at least one x_15 for which if x_15 were a mechanic, then x_15 is a writer, and that for all x_15, x_15 is not a writer we can infer that there is at least one x_15 for which x_15 is not a mechanic. From the fact that for all x_15, x_15 is a mechanic if and only if x_15 will sleep we can infer that for all x_15, if x_15 sleeps, then x_15 is a mechanic. From the fact that for all x_15, if x_15 sleeps, then x_15 is a mechanic, and that for all x_15, if x_15 were a mechanic, then x_15 is sleeping we can infer that for all x_15, x_15 will sleep if and only if x_15 is a mechanic. Finally, from the fact that for all x_15, x_15 will sleep if and only if x_15 is a mechanic, and that there is at least one x_15 for which x_15 is not a mechanic we can infer that there is at least one x_15 for which x_15 will not sleep, which contradicts that For all x_15, x_15 will sleep. Therefore, the answer is no.