The Trinity and contingent identity

I got thinking about the Trinity after the workshop on the metaphysics of theism at Leeds last week, and I got to wondering: has anyone ever suggested that the Trinity is a case of contingent identity? (The good thing about a blog is you can put out those ideas that are too weird for publication! All my thoughts on the philosophy of religion are a proper subset of that category.)

So forget the Trinity for the moment and focus on the father's relationship to the son: the idea is that they are actually identical, but contingently so, and that the father is a necessary existent but the son a contingent existent. In every world in which the son exists, he is identical to the father, but there are worlds in which the father exists and is not identical to the son because there are worlds in which the son does not exist (for the son to exist depends on an act of will on the part of the father, and he might not have so willed).

So there is of course a very tight connection between the father and the son: strict numerical identity - it doesn't get much tighter! Thus vindicating Jesus's claim that that father and he are one. But we can also quite easily, on this view, make sense of Jesus's claim that the father is greater than he is: he's a mere contingent existent, the father a necessary being - that's good grounds for saying that the father is greater.

How to fit in the spirit? Well perhaps the spirit is also a contingent existent, and also actually identical to the father (and, by transitivity, the son), but that there are worlds with son but no spirit and worlds with spirit but no son. So the idea is that although the father, the son, and the spirit are each numerically identical to the others, we can distinguish them by their differing modal profiles. For any two, while they're actually identical, they might not have been. But monotheism is easily seen to be a necessary truth, on this view (whereas other views of the Trinity threaten to commit us to tritheism): necessarily, there is only one God, for necessarily any divine being is numerically identical to the father.

Objection: how can they be numerically identical if they have differing modal profiles? Reply: well, we all know the contingent identity theorist has to resist the Leibniz law argument from differing modal profiles to numerical distinctness. Whatever story they're going to tell to make sense of contingent identity in general, let them tell it here.

Objection: but isn’t there a difference in non-modal properties as well? The father is atemporal, the son temporal, the son human the father not, etc? Reply: okay, we’re going to have to say something odd here. Perhaps we just deny the atemporality of the father, or perhaps we say that God is atemporal qua father but not qua son, etc (and hopefully unpack that and say what it means!). But every view of the Trinity ends up saying something a bit odd at this point – it’s not clear that there’s a particular objection to the contingent identity view here.

So, does anyone know if this has been discussed before, or see any problems with it that aren’t faced by all accounts of the Trinity?

(Posts on sane topics will resume once marking season is over, I suspect!)