Consider the following premises. For all x_4, x_4 is an electrician or x_4 is not a carpenter. For all x_4, x_4 is a scientist or x_4 is a carpenter. For all x_4, if x_4 were a sailor, then x_4 is an electrician. For all x_4, x_4 is not a scientist or x_4 is a sailor. Can we infer the following from them? There is at least one x_4 for which x_4 is not an electrician.
 From the fact that for all x_4, x_4 is an electrician or x_4 is not a carpenter we can infer that for all x_4, if x_4 were a carpenter, then x_4 is an electrician. From the fact that for all x_4, x_4 is a scientist or x_4 is a carpenter, and that for all x_4, x_4 is not a scientist or x_4 is a sailor we can infer that for all x_4, x_4 is a carpenter or x_4 is a sailor. Finally, from the fact that for all x_4, if x_4 were a carpenter, then x_4 is an electrician, that for all x_4, if x_4 were a sailor, then x_4 is an electrician, and that for all x_4, x_4 is a carpenter or x_4 is a sailor we can infer that for all x_4, x_4 is an electrician, which contradicts that There is at least one x_4 for which x_4 is not an electrician. Therefore, the answer is no.