Author Topic: Plantinga cheats with his variation of this argument, Craig continues that cheat  (Read 36206 times)

neopolitan

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In this article here, I describe the cheat.

Are there people who are seriously persuaded by this argument?  Surely some of you have worked out that there is something not quite right in it?

mazzgolf

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neopolitan - I see you are posting a lot recently.  Welcome to the forums BTW, but I hope this isn't an attempt just to drive traffic to your blog :) Perhaps it is best to summarize your thoughts in your posts here, rather than force people to click outside links and read large blog entries.

Also, have you searched the forums? There have been ALOT of back and forth over the Ontological Argument in here, people's objections to it, and responses. I would be surprised if your initial impressions weren't already addressed previously.

neopolitan

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I really try to avoid having my arguments shackled to those of others, who might have quite different perceptions on things.  I can't necessarily argue from those perceptions.

As for people here, I'd like to see if they, who are apparently interested in apologetics, can defend the positions put forward by Craig.

cpdavey24

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Fair enough, but can you summarize your own views on this topic here in the post, instead of a link to long blog post?

veka

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Hello, neopolitan.

What is this "cheat" used by Plantinga and Craig?

Best regards.
"Denial of knowledge of God is only as cogent as the conception of knowledge on which it is based." - William P. Alston

neopolitan

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Because it's not simple, I explain it in the linked document.

In >>>this article here<<<, I describe the cheat.

Are there people who are seriously persuaded by this argument?  Surely some of you have worked out that there is something not quite right in it?

It's a two layered cheat, involving vague definitions of "world" and a logical switcheroo.
« Last Edit: April 27, 2013, 09:23:50 AM by neopolitan »

veka

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All right. So how many years have you studied modal logic?
"Denial of knowledge of God is only as cogent as the conception of knowledge on which it is based." - William P. Alston

cpdavey24

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It's a two layered cheat, involving vague definitions of "world" and a logical switcheroo.

I don't know if you've read Plantinga's The Nature of Necessity, but in that book he gives a very detailed and formal definition of what a possible world is. As for the logical swicheroo, could you be more specific? I don't see why your ideas are so complex that they can't at least be encapsulated in a rough outline of some kind.

neopolitan

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I don't know if you've read Plantinga's The Nature of Necessity, but in that book he gives a very detailed and formal definition of what a possible world is. As for the logical swicheroo, could you be more specific? I don't see why your ideas are so complex that they can't at least be encapsulated in a rough outline of some kind.

I'm glad you mention "The Nature of Necessity".  You'd be aware that Plantinga himself says (p221):

Quote from: AlvinPlantinga
Hence our verdict on these reformulated versions of St. Anselm's argument must be as follows.  They cannot, perhaps, be said to prove or establish their conclusion. But since it is rational to accept their central premiss, they do show that it is rational to accept that conclusion. And perhaps that is all that can be expected of any such argument.

Given that he is specifically talking about the ontological argument that Craig uses (albeit reworded), it's interesting, isn't it?  The author himself suggests that it's not a proof.  So why is Craig using it as a proof?

The switcheroo involves treating two different forms of logic as if they were the same.  If you read The Nature of Necessity, you will see that Plantinga separates out all his claims with swathes of text.  He doesn't put things nice and neatly like Craig (my goodness, praise for Craig!)  For example, he goes to a lot of effort to talk about things being necessary if they are possible in Ch 7 and 8, then puts forward his ontological argument in Ch 10.  He thus puts some distance between his desired conclusion and the veiled reference to "vacuous truths" - statements which cannot be false, such as when discussing fictional characters.

Craig explicitly uses two "vacuous truths".  Then there is also the use of "maximally great being" which is just nonsense.  There is, today, a maximally great human being, the one who has the optimal blend of strength, intelligence and compassion, but I assure you that she is not existent in every continent and nor must she be in order to maintain her maximal greatness.  This doesn't go away if you start talking about multiple worlds, unless you have the preconception about maximal greatness, in which case the general acceptance of the truth value of Craig's first premise (the one he states after his assertion) disappears.

He's a cheat, you know he's a cheat, I don't quite understand why you don't accept that he's a cheat.

Biep

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There is, today, a maximally great human being, the one who has the optimal blend of strength, intelligence and compassion, but I assure you that she is not existent in every continent and nor must she be in order to maintain her maximal greatness.
Sorry, but have you understood the definition of 'maximally great' at all?
Quote
He's a cheat, you know he's a cheat, I don't quite understand why you don't accept that he's a cheat.
Please, this place is for substantive, irenic discussions.  Please add substance and remove the eristic bits.  You have a blog where you can be as substanceless and insulting as you want, but please do respect the rules of this forum.

« Last Edit: May 01, 2013, 08:03:52 AM by Biep »
-- Biep
I tend to post and run, but always hope to return eventually.  Don't hold your breath, though.

I have very little energy at the moment, so don't expect much of me right now.

ontologicalme

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Hi,


I'm glad you mention "The Nature of Necessity".  You'd be aware that Plantinga himself says (p221):

Quote from: AlvinPlantinga
Hence our verdict on these reformulated versions of St. Anselm's argument must be as follows.  They cannot, perhaps, be said to prove or establish their conclusion. But since it is rational to accept their central premiss, they do show that it is rational to accept that conclusion. And perhaps that is all that can be expected of any such argument.

Given that he is specifically talking about the ontological argument that Craig uses (albeit reworded), it's interesting, isn't it?  The author himself suggests that it's not a proof.  So why is Craig using it as a proof?


Proof of what? What Plantinga is saying is that proving the existence of God is not the objective of the OA (or natural theology for that matter), but to show that theism is the most rational option.

"...But since it is rational to accept their central premise, they do show that it is rational to accept that conclusion. And perhaps that is all that can be expected of any such argument".

A "maximally" great person, is not a necessary being, which is better than being just a contingent, contingency is not a great making property.

Best regards.

cpdavey24

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I'm glad you mention "The Nature of Necessity".  You'd be aware that Plantinga himself says (p221):

Quote from: AlvinPlantinga

    Hence our verdict on these reformulated versions of St. Anselm's argument must be as follows.  They cannot, perhaps, be said to prove or establish their conclusion. But since it is rational to accept their central premiss, they do show that it is rational to accept that conclusion. And perhaps that is all that can be expected of any such argument.


Given that he is specifically talking about the ontological argument that Craig uses (albeit reworded), it's interesting, isn't it?  The author himself suggests that it's not a proof.  So why is Craig using it as a proof?

It's true that Plantinga original held this view, but he changed his mind later and now claims his ontological argument is as good an argument as any other in philosophy. At any rate, even if Plantinga still held that his OA is not a proof, this doesn't mean that Craig or anyone else is somehow obligated to regard it as such. Perhaps Plantinga just doesn't appreciate the import of his own argument.

Quote
The switcheroo involves treating two different forms of logic as if they were the same.

I think you mean two different interpretations of modal logic? If so, could you be more specific? To my understanding, Plantinga and Craig both use some form of the Actualistic version of quantified S5. Where specifically in the argument is a different interpretation used?

Quote
Craig explicitly uses two "vacuous truths".

Where? And what do you mean by "vacuous"?

To my understanding, Craig's and Plantinga's argument can be formulated as follows:

Ex=x is a Maximally Exellent being

1.◊□(∃x)Ex
2. ◊□(∃x)Ex→□(∃x)Ex
3. ∴ □(∃x)Ex

(2) is a relatively uncontroversial theorem of S5, so as I see it, it all comes down to (1). At any rate, I don't see how the argument is invalid in any way unless you think (2) is an invalid theorem.

Quote
Then there is also the use of "maximally great being" which is just nonsense.  There is, today, a maximally great human being, the one who has the optimal blend of strength, intelligence and compassion, but I assure you that she is not existent in every continent and nor must she be in order to maintain her maximal greatness.

I think you are just talking past Plantinga and Craig here. Neither one defines Maximal Greatness the way you do, so at best this is just a straw man.

Maximal Greatness=df □(∃x)[(x is Omnipotent) & (x is Omniscient) & (x is Morally Perfect) &...)

Hence, Maximal Greatness has necessity built into the concept, so no contingent being, like a human, could be Maximally Great. Furthermore, the definition has all of God's Omni-predicates built in, so again no human can be Maximally Great. You may not think the definition is coherent, but it is a different definition than the one you use above.
Quote
This doesn't go away if you start talking about multiple worlds, unless you have the preconception about maximal greatness, in which case the general acceptance of the truth value of Craig's first premise (the one he states after his assertion) disappears.

I'm sorry, but I'm really not following you here. Are you saying that if one accepts the definition of Maximal Greatness above, then premise one becomes false? That can't be what you mean, but then what do you mean by saying the truth value of premise 1 disappears? Maybe you are talking about the epistemic justification of (1)?

Quote
He's a cheat, you know he's a cheat, I don't quite understand why you don't accept that he's a cheat.

Well, the word "cheat" implies some kind of intentional deception on Craig's part, and I just don't see any evidence for that. I'm willing to grant that he's wrong or mistaken or even that he has committed a modal fallacy of some kind. Philosophers do these kind of things all the time. But I'm not willing to call him a "cheat" unless some kind of evidence can be presented to show that he is intentionally trying to deceive.


neopolitan

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cpdavy24,

I've put together a response here.

Enjoy.  More to follow in a moment.

neopolitan

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Craig expresses what appears to be a rephrasing of Plantinga’s ontological argument this way:

1.   It is possible that a maximally great being exists.
2.   If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.
3.   If a maximally great being exists in some possible world, then it exists in every possible world.
4.   If a maximally great being exists in every possible world, then it exists in the actual world.
5.   If a maximally great being exists in the actual world, then a maximally great being exists.
6.   Therefore, a maximally great being exists.

The problems, in short are:

Line 1 (the assertion) refers to a “maximally great being” which, a priori, is just a being that is as great as it is possible to be.  Such a being could, conceivably be nothing more exciting than a particularly large, strong, intelligent and pleasant blue whale (Wally the Whale).  As cpdavy24 points out, hidden in the definition of “maximally great” is the assumption of “existence”.  Without such a preconception, however, this statement says very little.

Part of the implied argument for this assertion is that it is not necessary that it is not possible that the “maximally great being” to exist.  When the “maximally great being” is loaded up with characteristics the way it is, it actually becomes necessary that it doesn’t logically exist due to the problem of evil together with the claim that “maximal greatness” is the intersection of omnipotence, omniscience and “moral perfection”.  Even if one were to argue that “moral perfection” is not equivalent to omnibeneficence, you are still left with the problem of omnipotence being logically incoherent.  Can this maximally great being create something that it cannot destroy? If so, then it’s just created a limit for itself, and is therefore not omnipotent, otherwise it is simply stymied one step earlier in the process.

If omnipotence is abandoned, then the theist logician must also abandon free will on the part of the maximally great being, since that is logically incoherent with omniscience.  If a maximally great being knows everything, that includes the future and hence not only the future consequences of any actions but also which actions it will take.  Perhaps a sophisticated theist might want to argue for a maximally great being that makes one single extremely complicated decision that spans all of time, but this is inconsistent with the idea that humans can interact in any meaningful way with it.  It would be like interacting with a pre-recorded message.  Theism in this case would resolve down to a form of deism.  Given that, practically, deism is entirely compatible with atheism (with the single exception of the creation event), such an argument by the theist is fraught with danger.

Line 2 is “vacuously true”.  Sure, if a maximally great being possibly exists, I’d agree that it possibly exists somewhere - it can't be both possible and impossible in every possible world.  Your problem is that Craig argues elsewhere that the target of this argument doesn’t exist in space, so it doesn’t have a “where” attached to it.  So, over all, Craig’s cumulative case is incoherent - he has to abandon either this one or his arguments in which he removes his god from the spatial universe.

Line 3 begs the question.  If there is a maximally great being, who just happens to be as good as beings can be, there’s no reason to presume that that being will have an existence that stretches across all worlds.  (Craig answers the begged question via Plantiga’s assertion that “maximal greatness” includes the quality of existence across all possible worlds.)

Lines 4 and 5 are, again, “vacuously true”.  Yes, if a being exists in every possible world, then it exists in the actual world because the actual world is a demonstrably possible world, and existing in the actual world necessitates existence.  (Again though, the target of the argument is argued elsewhere by Craig to not exist in this world.)

So, for those whining about it, you finally have a brief outline of the problems.  You’re welcome.

ontologicalme

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I just an amateur here,
but this
1.◊□(∃x)Ex
2. ◊□(∃x)Ex→□(∃x)Ex
3. ∴ □(∃x)Ex

Does not look as the correct Plantinga´s OA formalization.

I need to recheck.

 

anything