If the first god is a causally sufficient condition (in the strong sense) of the existence of at least one contingent being, then the second god is not a necessary condition of the existence of at least one concrete object distinct from itself.
(1*) is sufficient to yield our conclusion. For if the first god is a causally necessary condition of the existence of every other concrete object, then the second god is not a causally sufficient condition (in the strong sense) of the existence of any contingent being. Similarly, if the first god is a causally sufficient condition (in the strong sense) of the existence of at least one contingent being, then the second god is not a necessary condition of the existence of at least one concrete ob