Many-One Identity and the Trinity

Trinitarians claim there are three Divine persons each of which is God, and yet there is only one God. It seems they want three to equal one. It just so happens, some metaphysicians claim exactly that. They accept Composition as Identity: each fusion is identical to the plurality of its parts. I evaluate Composition as Identity's application to the doctrine of the Trinity, and argue that it fails to give the Trinitairan any options he or she didn't already have. Further, while Composition as Identity does give us a new way to assert polytheism, its help requires us to endorse a claim that undercuts any Trinitarian motivation for the view.