The modal ontological argument for God

[Disagreeable]

Modal Ontological Argument
[Short form]

P1. If a god is possible it exists in every possible world
P2. If a god exists in every possible world then it would exist in this world as this world is possible
C. God exists

***

My response to this argument is that just because God is logically possible it doesn't make God metaphysically possible. So we can just ask for a justification for why God is metaphysically possible.

[zebo-the-fat]

It seems to me that the important word here is IF

[Sheldon]

Modal Ontological Argument
[Short form]

P1. If a god is possible it exists in every possible world
P2. If a god exists in every possible world then it would exist in this world as this world is possible
C. God exists

***

My response to this argument is that just because God is logically possible it doesn't make God metaphysically possible. So we can just ask for a justification for why God is metaphysically possible.

P1 hinges on how one is defining a deity, I would need see possibility objectively demonstrated before I accept it

P2 Since I don't accept P1, this is just a circular reasoning fallacy. 

I can't accept the conclusion logically follows, since I don't believe the premises are true. 

Now try this, replace god with unicorn, and explain to me what the argument loses? All one need do is define anything in the way apologists arbitrarily define god, and the argument loses nothing.

[The Grand Nudger]

You not accepting a premise doesn't make the next premise a fallacy. It just means that you don't accept a premise. In this case, the premises you've decided to reject and consider circular are a bare bones statement of the s5 theory of modal logic.

I don't think it's accurate to say that any arbitrary definition would work - because it's really just the one thing or quality or attribute or x that the argument works -on-. Necessity. You could do away with omnipotence, omniscience, and moral perfection..for example....and it would not impact the argument - though it would certainly disappoint some christians. Frankly, you could discard those things for an existent god and it would still be a christian problem - not a god problem or a logical problem.

[Sheldon]

You not accepting a premise doesn't make the next premise a fallacy.  

Without P1, P2 has all the appearances of being circular, since stating "a deity exists in all possible worlds" would be an assumption of the conclusion it exists in this one, yes it follows, but then it would since the first part assumes the second. 

However since (P2) says IF at the start, then my assertion goes too far. 

Though before I accept a deity exists in all possible worlds or anywhere, I would need to see this demonstrated in some objective way, I don't think the argument establishes a deity is possible. 

Parenthetically the conclusion in the argument only follows IF a deity is possible. (Which is of course what it says) However I am also dubious that IF a deity is possible, it follows (in P1) that it exists in every possible world?

Ultimately one would need to demonstrate a deity is possible, or the argument does not seem like a  compelling reason to believe a deity exists anywhere. 

I don't think it's accurate to say that any arbitrary definition would work - because it's really just the one thing or quality or attribute or x that the argument works -on-. Necessity.

My apologies if I misunderstand here, but are you saying that one would have to accept a priori, that a deity is necessary, in order for the argument to work? Since the argument seems to argue existence based on whether a deity is possible. So is possibility that one attribute you're referring to?

As I said if we replace god with unicorn, then the argument doesn't appear to lose anything, not to me anyway?

[The Grand Nudger]

Is the unicorn a necessary being? Then the argument works the same way. Is it not? Then the s5 theory of modal logic does not apply.

We could expand the statement for clarification - and we don't have to use gods. If an x is possibly necessary in any possible world..and the s5 theory of modal logic is true/applicable/informative...then the statement "x exists" is true in all possible worlds.

Plantinga would agree with the essence of your remarks, though, in that no one thinks the argument is compelling to anyone who doesn't already believe in gods.

[Sheldon]

Is the unicorn a necessary being?  Then the argument works the same way.  Is it not?  Then the s5 theory of modal logic does not apply.

Yes, sorry that was my point, if we accept that X is possible then the argument works, no matter what X is.

If an x is possibly necessary in any possible world..and the s5 theory of modal logic is true/applicable/informative...then the statement "x exists" is true in all possible worlds.

This of course then requires that first step, that someone believe X is possible, which explains why apologists so often are amazed when I don't accept the conclusion of the argument, it's because I would first need to believe a deity is possible. 

Plantinga would agree with the essence of your remarks, though, in that no one thinks the argument is compelling to anyone who doesn't already believe in gods.

They shouldn't, but I have encountered people who do seem genuinely surprised I remain unconvinced a deity exists.

[Disagreeable]

And so the question remains: is God possible?

[Sheldon]

And so the question remains: is God possible?

Well even if one accepted a deity is possible, this gets you no closer to Jesus or Allah, than it does to Zeus or Apollo.

[zebo-the-fat]

And so the question remains: is God possible?

Well even if one accepted a deity is possible, this gets you no closer to Jesus or Allah, than it does to Zeus or Apollo.

So many gods to pick from... and they are all true amazing!