Consider the following premises. For all x_7, x_7 is not a carpenter. For all x_7, if x_7 writes a letter, then x_7 is running. For all x_7, if x_7 goes running, then x_7 is a carpenter. For all x_7, if x_7 were an astronaut, then x_7 is writing a letter. There is at least one x_7 for which if x_7 goes running, then x_7 is an astronaut. Can we infer the following from them? For all x_7, x_7 is an astronaut.
 From the fact that for all x_7, if x_7 goes running, then x_7 is a carpenter, and that for all x_7, x_7 is not a carpenter we can infer that for all x_7, x_7 will not go running. From the fact that for all x_7, if x_7 were an astronaut, then x_7 is writing a letter, and that for all x_7, if x_7 writes a letter, then x_7 is running we can infer that for all x_7, if x_7 were an astronaut, then x_7 is running. From the fact that for all x_7, if x_7 were an astronaut, then x_7 is running, and that there is at least one x_7 for which if x_7 goes running, then x_7 is an astronaut we can infer that there is at least one x_7 for which x_7 is an astronaut if and only if x_7 will go running. Finally, from the fact that there is at least one x_7 for which x_7 is an astronaut if and only if x_7 will go running, and that for all x_7, x_7 will not go running we can infer that there is at least one x_7 for which x_7 is not an astronaut, which contradicts that For all x_7, x_7 is an astronaut. Therefore, the answer is no.