296-297Could there be two worlds, two infinite systems of monads with no world in common? It is obvious that this is impossible. There might be two groups of monads which had no factual social relationships, but the monads or social group to which my monad did not belong are nevertheless intentional correlates of a constitutive system within my monad, and my monad has for me the sense of an intentional correlate of constitutive systems in them. There can be, accordingly, but one system of transcendental existent monads, and correlatively but one intersubjective natural world. This natural world must in turn exist as phenomenon if the compossibility of other monads is implied by the intrinsic structure of my monad. And this, we have seen, is the case. On the other hand, it is evident that, as Leibniz asserted, there are an infinite number of possible systems of monads, each system non-compossible with the other, but each consistent within itself. Each of these purely possible systems would include a different purely possible intersubjective natural world. The evidence of the pure possibility of each of these non-compossible monad-systems is founded in the evidence of purely possible free-variation of my own factual transcendental awareness. The evidence that they are con-compossible is founded in the evidence that various purely possible determinations of myself are not compossible, and the apodictic evidence of my own existence as one of the purely possible variants of myself, founds the evidence that one of the purely possible systems of monads, and one of the purely possible intersubjective natures exist.