Consider the following premises. For all x_6, if x_6 were a carpenter, then x_6 is a sailor. There is at least one x_6 for which x_6 will play squash if and only if x_6 is a carpenter. For all x_6, if x_6 were a sailor, then x_6 is a carpenter. For all x_6, x_6 will not play squash. Can we infer the following from them? For all x_6, x_6 is a sailor.
 From the fact that there is at least one x_6 for which x_6 will play squash if and only if x_6 is a carpenter, and that for all x_6, x_6 will not play squash we can infer that there is at least one x_6 for which x_6 is not a carpenter. From the fact that for all x_6, if x_6 were a sailor, then x_6 is a carpenter, and that for all x_6, if x_6 were a carpenter, then x_6 is a sailor we can infer that for all x_6, x_6 is a sailor if and only if x_6 is a carpenter. Finally, from the fact that for all x_6, x_6 is a sailor if and only if x_6 is a carpenter, and that there is at least one x_6 for which x_6 is not a carpenter we can infer that there is at least one x_6 for which x_6 is not a sailor, which contradicts that For all x_6, x_6 is a sailor. Therefore, the answer is no.