The Ontological Argument - valid or debunked?

[SteveII]

I take issue with the concept of god being necessary.  The video posted above highlights the absurdity of it  -  following the structure of the argument you can claim that anything is possible and possibly necessary without support.  I think giant space faring whales who shoot Skittles out of their blowholes are possible and possibly necessary.  Therefore they're necessary.  Therefore it exists.

Do you see the absurdity?  You can't just pull anything out of your ass, apply modal logic to it, and then say "Ta da!"  You still need to demonstrate that these creatures aren't just possible, but that they're possibly necessary.  Ultimately, you can't logic something into existence.

You are correct that the argument hangs on the concept of necessary. The opposite of necessary is contingent. Since being contingent on something is a defect it would not be considered maximally great to be contingent. A maximally great being would be a necessary being because it could not be contingent on another (then that would be a greater being). 

You can dream up all the parodies you like but you have to answer the question of why whatever example is necessary rather than contingent.

[IATIA]

To defeat the argument, you are left with showing why premise 1 is not true. This would require you to show that the concept of a maximally great being (God) is illogical.

The whole ontological argument is simply that god is possible, therefore god exists.

For this argument to even have a chance at working, one must show that a god is possible.

I do not claim that a god exists.

I do not claim that a god is necessary.

I do not claim that a god is possible.

[Esquilax]

You are correct that the argument hangs on the concept of necessary. The opposite of necessary is contingent. Since being contingent on something is a defect it would not be considered maximally great to be contingent. A maximally great being would be a necessary being because it could not be contingent on another (then that would be a greater being). 

You can dream up all the parodies you like but you have to answer the question of why whatever example is necessary rather than contingent.

Okay, I refuse to believe that you're really this obtuse. Are you just making fun of us, here?

Why is a maximally great being necessary rather than contingent? If you're just building necessity into the definition of maximally great, then first of all congratulations, you've got subjective opinion number 9,800,654 on what constitutes maximally great, and unfortunately for you your personal opinions are no more binding or objective than anyone elses'. Second of all, you've got the mother of all circular, question begging, garbage fire arguments here, because you're building the thing you're trying to prove (the existence of god) into the definition of the thing itself. You might as well just say "god exists because existing is a thing that god does." Whoop-de-freaking-do.

And it's so clearly circular that I have a hard time accepting you don't see it: why does god exist? Because god is a maximally great being. So what? "Maximally great" includes necessity in its criteria, so god exists necessarily. Therefore, god exists. So basically, god exists because you've defined a label for him that includes existence as part of that? Yes, maximal greatness means he exists.

Don't bullshit us, Steve. If I'd made a logical argument for why god couldn't exist that began with me bestowing upon god a title, and ended with me telling you that title includes non-existence as a part of it, you would dismiss that argument, quite rightly, so fast. Don't use arguments you wouldn't accept if they didn't line up with what you already believe, it's breathtakingly lazy.

[GrandizerII]

You are not pointing out why a maximally great being is illogical.

Is a maximally shitty being illogical? if not I nominate Trump for the position.
What is maximally great? Sounds a bit nebulous to me.

Omnipotent, omniscient, and wholly good, according to Plantinga. It's logically incoherent as Jorg said, and any indicator that it is short of perfect should render it unnecessary, but I'm not sure if it's even worth explaining how with Steve, as I sense it will just be the usual: circles and circles.

[Gemini]

If arguments like the teleological argument are gateway drugs into the sordid world of theological sophistry, the ontological argument is the hard stuff. By the time you believe that, you're mainlining a priori reason. You're a hard, pipe-hittin' apologist.

Although it's tragic to watch someone descend into this level of navel-gazing, it's probably good for atheism. The ontological argument is notoriously unpersuasive. You'd probably make a better case for Christianity by dropping trou and running around yelling, "I'm a weiner!"

[KevinM1]

According to modal logic, the term necessary means that the thing in question is not possibly false. Yet, a tri-omni being isn't innately true. It goes back to the problem with premise 1 - demanding existence because the desired conclusion requires it.

Which, I believe, is a concession even Plantinga admits to.

[Fake Messiah]

A maximally great being would be a necessary being because it could not be contingent on another (then that would be a greater being). 

You can dream up all the parodies you like but you have to answer the question of why whatever example is necessary rather than contingent.

And how much great can you imagine this being? Can it be so great that it can create a rock so heavy that it can not lift it?

[SteveII]

As Irrational said, it is important to understand the S5 modal logic that if something is even possibly necessary, it is actually necessary. (which would answer Kevin's question about the jump from 2 to 3.)

Then I would point out that "necessity," where it isn't supported in any way, is not different than a petulant foot stomp and a yelled "because I said so!"

I need to clarify. The difference is between epistemic possibility and metaphysical possibility. Epistemic possibility is simply "for all we know something is possible". On the other hand, to illustrate metaphysical possibility take a math equation 24673244/8=3005567. While we might say "for all we know" this might be true, but if it is true, than it is necessarily true if it is false than it is necessarily false. If a maximally great being exists, it exists necessarily in a metaphysical sense. Therefore, God’s existence is either possible or impossible.

@Esquilax, one of your objections to maximally great being is that something "slightly more great" can be imagined makes no sense. What could be greater than an omnipotent, omniscient, morally perfect, and necessary being?

An omnipotent, omniscient, morally perfect, necessary being that can eat the one you're proposing. What's greater than that? Same deal, but it can eat the one preceding it. And so on. And so forth. Greatness has no upper bound.

Then you have simply changed the definition of omnipotent. Equivocating. An omnipotent God could prevent getting eaten. 

More importantly, did you just not notice that this argument of yours is just one big argument from incredulity and ignorance? Your inability to fathom something greater is not an argument against my position.

First, at most that would undercut theistic belief, not that theism is false. Second, a limited grasp of God's properties does not entail that our conception of God is false. Third, we can believe in God without being able to grasp all there is to know about God (because that would be impossible).

[Little lunch]

It's so funny how x-tians try to prove there is a god with a bunch of words that sound as complicated as legislation and then, even if their proof was conclusive, when asked which god it is, they would point at their contradictory, fucked up bible.
Sorry, but how pompous and at the same time deluded is fucking that?

[Esquilax]

I need to clarify. The difference is between epistemic possibility and metaphysical possibility. Epistemic possibility is simply "for all we know something is possible". On the other hand, to illustrate metaphysical possibility take a math equation 24673244/8=3005567. While we might say "for all we know" this might be true, but if it is true, than it is necessarily true if it is false than it is necessarily false. If a maximally great being exists, it exists necessarily in a metaphysical sense. Therefore, God’s existence is either possible or impossible.

That's... not exactly a big conclusion.

Then you have simply changed the definition of omnipotent. Equivocating. An omnipotent God could prevent getting eaten. 

My point is that there exists, if we so wish to discuss it, an infinite number of ever increasingly maximally great beings, each one identical to the last, only with the ability to limit the one preceding it. You propose an omnipotent god, and this is your maximally great being, in response I propose a being with an identical power set, plus one more ability which allows it to weaken your god, thus making it the maximally great being, and so on, ad infinitum. Yes, I suppose in some sense I'm simply broadening the definition of omnipotence, but we're not talking about omnipotence, we're talking about maximally great beings within the premises of the ontological argument, and the fact that I can erect an infinite regress around that at all demonstrates my point: the concept of a maximally great being is logically incoherent in that any maximally great being that actually exists serves as little more than a platform from which other, more powerful beings can be posited. The moment you show a demonstrably real maximally great being is the moment that being can be surpassed simply by proposing additional beings capable of negatively influencing the extant one. And you can say that a really omnipotent god could prevent that, but that's the point: that god would no longer be omnipotent because I've built into the power set of my being the ability to take that power away from yours, and it's hardly like we're discussing real things anyway, we're just talking in hypotheticals. You've no reason to dismiss my concept out of hand.

Greatness has no defined criteria, nor an upper bound, and this is the problem here. The first premise of the ontological argument is roughly akin to saying "the greatest possible number exists," and then you, as a numberist, telling me what number you think that is. 64, you say, for the benefit of my analogy. Then I rightly point out that 65 is a higher number than 64: you just telling me that 64 is the highest possible number necessarily, therefore it can prevent 65 from being higher... well, that just doesn't make any sense, does it?

First, at most that would undercut theistic belief, not that theism is false. Second, a limited grasp of God's properties does not entail that our conception of God is false. Third, we can believe in God without being able to grasp all there is to know about God (because that would be impossible).

First, "I know it's an argument from ignorance, but I'm going to believe in the conclusion anyway," is one of the most intellectually dishonest things I've ever heard. Second, I'm not talking about your belief in god generally, here I'm talking about the ontological argument and why it fails. Third, regardless of your beliefs, surely you can see the problems with defending them using clear logical fallacies?