Leibniz's point is that, since the Adam of the actual world (call him “Adam@”) has a complete concept containing all of his properties and since Adam@ (or any substance) expresses the entire world of which he is a member, Adam@ could not exist in a different world. Moreover, if any of Adam@'s properties were somehow changed, then the resulting being would not be Adam@. This is indeed an important consequence of his Principle of the Identity of Indiscernibles. When we speak of the Adam who broug