Sunday, May 31, 2009

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!)


Lee Walters said...


Wiggins discusses a *relative* identity account of the Trinity in S&SR pp.45ff, but here he is discussing non-modal predciation: how Fa & ~Fb and yet a=b, which does not seem to be your concern?

So unless you go the relative identity route, you'll have to say that God the Father was crucified on the cross, although this is perhaps not assertable for some reason.


Ross Cameron said...

hi Lee,

Yes, and Geach also defends a relative identity account of the Trinity; but that's very different from the current proposal, where identity behaves classically.

And yes, it will be true that the one entity that is God was crucified, simpliciter, but perhaps we can say that he was crucified qua son and not qua father (and hopefully, we won't have to leave it at that!).

Mark said...

van Inwagen also presents, defends, but ultimately rejects the relative identity account of the Trinity in his The Possibility of Resurrection and other Essays.

Louis said...

Fun topic for a Sunday afternoon! Aren't you going to have to go counterpart-theoretic about relative greatness and existential dependence, in addition to modal features and temporality? The father, after all, is not greater than the father (nothing is); and the existence of the father does not depend on an act of will of the father -- at least, not on the act of will in question. I don't think of existential dependence as analyzable in modal terms. I'd be surprised if you do.

- Louis

Jonathan D. Jacobs said...

Philosophically, I see nothing objectionable that isn't already objectionable about contingent identity.

But theologically, I'm quite certain there are any number of heresies involved. (Here's the first one that came to mind: Patripassionism, the claim that the Father suffered on the cross. I'm sure I could come up with at least five more.) But if that's not a concern, and the philosophical problems with contingent identity don't seem persuasive, then it might work for you.

Adam Pastor said...

Greetings Ross Cameron

On the subject of the Trinity,
I recommend this video:
The Human Jesus

Take a couple of hours to watch it; and prayerfully it will aid you to reconsider "The Trinity"

Yours In Messiah
Adam Pastor

Simon Hewitt said...

I don't think the historical claim *is* either that the Son is a contingent existent or that he is absolutely identical to the Father (as opposed to, identical qua God, Geach style). I think the claim, rather is, that all three persons of the Trinity, are necessary existents, that none is identical to the other, and that all three *are* (in a sense which is going to require philosophical analysis) the same God. Seems considerably less metaphysically problematic than your reading - assuming one doesn't have problems with necessary existents as such.

I suppose I'm confused about what would motivate the contingent identity claim r.e. the Trinity. A better case of prima facie contingent identity from Christian theology might be the identity claimed between the man Jesus and God the Son.

fateoficarus said...


Perhaps to explain away the atemporality of God, it could be urged that God is one of Lewis’s transworld individuals under some ‘divinity’ counterpart, and the trinity, which are contingently identical to one another, are God’s three modal parts. I'm not sure to what extent that respects the original idea, but it's a thought.