Friday, August 24, 2012

Modal realism and God

According to David Lewis's modal realism, every possible world exists as a concrete universe, and a proposition is possible provided it holds at some universe. But this seems incompatible with theism. For necessarily God believes every truth, and we can now run the following argument.

Necessarily, if p is true, God believes p. So, if p is possible, possibly God believes p. Thus, possibly, God believes that there are no horses, since the proposition that there are no horses is possibly true. So there is a universe, say u1, at which God believes that there are no horses. Now God either actually has this belief or not. If he actually has this belief, then he actually has conflicting beliefs, since he actually believes that there are horses. But God does not have conflicting beliefs. So we have to say that while at u1 God believes there are no horses, actually God instead believes there are horses. Thus, what propositions God believes differs between universes. But how could that make any sense? Granted, perhaps our beliefs can be localized to brain hemispheres and then at a location in my left hemisphere I believe p and at another I don't. If that can be made sense of, then one could give a sense to the locution "believes p at x". But God's beliefs surely do not have any such localization. Wherever God is present, he is wholly present. He is not a material being to have partial presence of the sort that might allow for a spatial distribution of our beliefs.


appearedtoblogly said...

Your argument is very similar to several more general arguments discussed by Richard Brian Davis in “God and Modal Concretism” Philosophia Christi 10/1 (2008), pp. 59ff.

Heath White said...

I'm not sure I see the problem.

Surely no matter how you interpret modality, God has different beliefs in different possible worlds. That's because different propositions are true in different possible worlds.

Maybe you are thinking there is just one God for all of these concrete Lewisian universes. But surely Lewis (if he were going along with the necessary being idea) is going to say that each universe has its own individual deity, all of which are related by the counterpart relation. So each of them can believe all the true propositions in his own concrete universe.

Alexander R Pruss said...

Yes, I am assuming monotheism. :-)

Heath White said...

Well, there's only one *actual* God.... :-)

Starless Night said...

I'm more than willing (and probably expecting) to be proven wrong but it seems as though if there are no horses in u1 then God would not know that the horses exist, but rather that horses exist at u1.

Would it be plausible to say that under modal realism contingent propositions such as p actually contain an implicit description of which world they claim to apply to?