Monday, August 21, 2017

A theological argument for four-dimensionalism

One of the main philosophical objections to dualist survivalism, the view that after death and prior to the resurrection we continue existing as disembodied souls is the argument that I am now distinct from my soul and cannot come to be identical with my soul, as that would violate the transitivity of identity: my present self (namely, I) would be identical to my future self, the future self would be identical to my future soul, my future soul would still be identical to my present soul, and so my present self would be identical with my present soul.

(This, of course, won’t bother dualists who think they are presently identical with souls, but is a problem for dualists who think that souls are proper parts of them. And the latter is the better view, since I can see myself in the mirror but I cannot see my soul in the mirror.)

It’s worth noting that this provides some evidence for four-dimensionalism, because (a) we have philosophical and theological evidence for dualist survivalism, while (b) the four-dimensionalist has an easy way out of the above argument. For the four-dimensionalist can deny that my future self is ever identical with my future soul, even given dualist survivalism. My future self, like my present self, is a four-dimensional temporally extended entity. Indeed, the future self and the present self are the same four-dimensional entity, namely I. My future soul, like my present soul, is a temporally extended entity (four-dimensional if souls have spatial extension; otherwise, one-dimensional), which is a proper part of me. And, again, my future soul and my present soul are the same temporally extended entity. At no future time is my future self identical with my future soul even given dualist survivalism. At most, it will be the case that some future temporal slices of me are identical with some future temporal slices of my soul.

9 comments:

Christopher Michael said...

How is this an argument for four-dimensionalism as such? This is just an argument for the proposition that although the body is a part of me, it isn't an essential part. Now, of course, there are problems that attend the rejection of mereological essentialism, but four-dimensionalism isn't the only way to solve them. Or do you think that four-dimensionalism is the only viable position once one has rejected mereological essentialism?

By the way, how does you four-dimensionalism differ from Sider's? Would you take his book to be representative of your own 4D view?

Alexander R Pruss said...

In the body of the post I was more careful: I said it's "evidence", not an "argument". Yes, it's not the only solution.

My own four-dimensionalism is not committed to unrestricted temporal parts, and hence escapes the Merricks argument against Sider's.

Justin Mooney said...

Isn't this just a version of the puzzle in van Inwagen's paper "The Doctrine of Arbitrary Undetached Parts"?

Alexander R Pruss said...

Yeah, but it's harder to get out of than the standard versions. For instance, is harder to deny that the soul now exists than to deny that Tibbles without tail exists when the tail is attached.

Speed Limit Forty said...

Why not think that during this life and after the general resurrection we are constituted by the composite of our soul and body and during the intermediate state we are constituted by our souls? (I am suggesting this under the assumption that constitution isn't best analyzed in terms of identity or temporal parts.)

Alexander R Pruss said...

One can do that, but then one violates mereological axioms that a lot of people think are plausible (e.g., weak supplementation), because on this view, one's soul is a proper part of one in the interim state but one has no proper parts beyond the soul. I don't buy those mereological axioms myself, though.

Speed Limit Forty said...

Oh, I took it that, on this proposed constitution view, the soul wouldn't be a proper part of you. Would there be a problem here if we don't understand composition mereologically either?

Alexander R Pruss said...

Well, it seems to be a part, and it's not the whole, so that would make it a proper part.

Maybe, though, the view would deny that the soul is a part of me, even now. Perhaps constituents are not always parts? Is that the view?

Speed Limit Forty said...

Yeah, I was proposing something like that.