I've read about modal ontological arguments for the existence of God, and it seems some atheists think that the same sort of argument can be used to argue the non-existence of God:
1. If God exists, God is necessary.
2. It is possibly the case that God doesn't exist.
3. Therefore God is not necessary.
4. Therefore God doesn't exist (modus tollens, from 1)
So /lit/, what's wrong with this argument?
>>7509866
it's not literature
>>7509868
There is plenty of literature on this subject.
This doesn't belong on /lit/. Repost on /his/, please. I'd like to discuss it.
>>7509879
>>7509878
I've had insightful feedback on /lit/ about shit like this before, particularly from a tripfag or two. dunno if this counts as a source, but I've specifically read about alvin plantinga's and william lane craig's modal ontological arguments, and the atheists who seem to think the argument goes both ways, that I'm aware of, are exclusively found online.
>>7509866
I don't see how claim #2 is self-evident.
This is a really shitty argument/discussion too.
>>7509893
How is it not self-evident? Of course it is epistemically possible that God doesn't exist.
>>7509866
>if God exists, God is necessary
This isn't the same thing as if God isnt necessary, God doesn't exist. So 4 doesn't hold.
If God exists --> God is necessary
Isn't
If God exists <--> God is necessary
>>7509866
1 is already wrong or improvable, regardless of which version argument you're using. How do we know that "god is necessary" if it exists?
The normal ontological argument is also wrong for similar reasons. I don't buy the "maximally great being" stupidity that somehow makes such things "necessary". We are working with things that we haven't proved/disproved or are unable to prove/disprove and asserting them as facts.
>This isn't the same thing as if God isnt necessary, God doesn't exist.
I think it can be argued that it is the same thing. The premise relies on the notion that by definition, any existant God must necessarily be necessary.
>If God exists --> God is necessary isn't if God exists <--> God is necessary
For the same reason, that can be argued as well. An existent God is necessary, and a necessary God is existent.
>>7509907
It is a shitty argument, but what you're saying isn't true either: if 1 and 3 are correct, 4 is correct as well because we are indeed talking about a material implication A --> B.
A --> B is true only if A is false or B is true. Therefore, if B (God is necessary) is false, A (God exists) must also be false for the statement to be true.
>>7509907
damn boy
((a->b)&~b) -> ~a
>>7509898
idk depending on what you take your definition of god to be, the argument can be circular. Like what conception of god is at stake here?
>>7509866
>>7509898
This might be a fallacious point but it does seem to me that 2 is a problem. It seems question begging, if God exists then it is not possible that God doesn't exist, our skepticism as to his existence is neither here nor there.
>>7509908
It is implicit in the definition of God that God is necessary. When dealing seriously with arguments concerning God we are not talking about a cartoon of a bearded guy sitting on some clouds, we are talking metaphysical God with a capital G. I don't think there are many, if any, serious conceptions of an abrahamic God that don't include His necessity.