Consider the following premises. For all y, y will not sleep. John is a soldier if and only if James is curious. For all y, y is a soldier if and only if y will sleep. Can we infer the following from them? James is curious.
 From the fact that for all y, y is a soldier if and only if y will sleep, and that for all y, y will not sleep we can infer that for all y, y is not a soldier. From the fact that for all y, y is not a soldier we can infer that John is not a soldier. Finally, from the fact that John is a soldier if and only if James is curious, and that John is not a soldier we can infer that James is not curious, which contradicts that James is curious. Therefore, the answer is no.