Consider the following premises. For all x, x is rich or x will climb a mountain. For all x, if x were rich, then x is curious. For all x, if x were curious, then x is a cashier. For all x, x is a cashier if and only if x will climb a mountain. Can we infer the following from them? There is at least one x for which x is not a cashier.
 From the fact that for all x, if x were rich, then x is curious, and that for all x, if x were curious, then x is a cashier we can infer that for all x, if x were rich, then x is a cashier. From the fact that for all x, x is a cashier if and only if x will climb a mountain we can infer that for all x, if x climbs a mountain, then x is a cashier. Finally, from the fact that for all x, if x were rich, then x is a cashier, that for all x, if x climbs a mountain, then x is a cashier, and that for all x, x is rich or x will climb a mountain we can infer that for all x, x is a cashier, which contradicts that There is at least one x for which x is not a cashier. Therefore, the answer is no.