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The Ontological Argument proves that God exists!

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Voting Style: Open Point System: 7 Point
Started: 3/30/2013 Category: Religion
Updated: 5 years ago Status: Post Voting Period
Viewed: 2,312 times Debate No: 31902
Debate Rounds (4)
Comments (11)
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My opponent takes the position that the Ontological Argument is proof for the existence of God and assumes the burden of proof. You are welcome to present any type of Ontological Argument for God that you like assuming that your definition of God secedes that he is omnipotent, omniscient, and morally perfect.

I will assume the Con position.

Rounds will work as follows:
R1. Acceptance and state Ontological Argument.
R2. Arguments and rebuttals.
R3. Arguments and rebuttals.
R4. Rebuttals and conclusion.



Alvin Plantinga's Modal Ontological Argument

P1: It is possible that a maximally great being exists.
P2: If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.
P3: If a maximally great being exists in some possible world, then it exists in every possible world.
P4: If a maximally great being exists in every possible world, then it exists in the actual world.
P5: If a maximally great being exists in the actual world, then a maximally great being exists.
C: Therefore, a maximally great being exists.

A maximally great being (MGB) is a being with all great-making properties to their maximal extent.

A possible world is any logical state of affairs. It does not mean an alternative universe, multiverse, etc

The actual world is the logical state of affairs we presently live in.

An impossible being is a being that cannot exist in any possible world because it has contradictory properties. An example of this would be a being that could do everything but do nothing at the same time, or a square circle.

A necessary being is a being that exists because of its own nature and exists in every possible world


Debate Round No. 1


I'd like to thank my opponent for accepting this debate. With that said, here we go!

Pro presents Alvin Plantinga's modal Ontological Argument. All Ontological Arguments for God’s Existence are a priori arguments and are thus subject to the same criticism that I will present in this round. Nevertheless, I will address Plantingas modal version of it in round three.

A Priori

It is widely accepted that the first [and most famous] Ontological Argument was proposed by [1] Anselm of Cantebury in 1078. Anselm defined God as "that than which nothing greater can be conceived", and then argued that this being could exist in the mind.

Even [2] Thomas Aquinas, objected to Anselm's argument. He suggested that people cannot know the nature of God and, therefore, cannot conceive of God in the way Anselm proposed. The Ontological Argument would be meaningful only to someone who understands the essence of God completely. [3] Aquinas reasoned that, as only God can completely know his essence, only he could use the argument.

A priori [1] knowledge or justification is independent of experience. Galen Strawson wrote that an a priori argument is one in which "you can see that it istrue just lying on your couch. You don't have to get up off your couch and go outside and examine the way things are in the physical world. You don't have to do any science."

Scottish philosopher and empiricist David Hume argued that nothing can be proven to exist using only a priori reasoning. In Dialogues concerning Natural Religion he proposes a criticism that goes as follows[4]:

“...there is an evident absurdity in pretending to demonstrate a matter of fact, or to prove it by any arguments a priori. Nothing is demonstrable, unless the contrary implies a contradiction. Nothing, that is distinctly conceivable, implies a contradiction. Whatever we conceive as existent, we can also conceive as non-existent. There is no being, therefore, whose non-existence implies a contradiction. Consequently there is no being, whose existence is demonstrable.

Hume also suggested that, as we have no abstract idea of existence (apart from as part of our ideas of other objects), we cannot claim that the idea of God implies his existence”

As is readily evident, each version of the Ontological Argument rests on the assumption that the concept of God, as it is described in the argument, is [5] self-consistent. But many philosophers are skeptical about the underlying assumption, and that this idea of the all or maximally-great and all or maximally-perfect being is possible and implies no contradiction.” Here is the problem:

Let us suppose, [6] that there were just three positive properties X, Y, and Z; that any two of them are compatible with each other; but that the presence of any two excludes the remaining one. Then there would be three possible beings, namely, one which combines X and Y, one which combines Y and Z, and one which combines Z and X, each of which would be such that nothing superior to it is logically possible.

For the only kind of being which would be superior to any of these would be one which had all three properties, X, Y, and Z; and, by hypothesis, this combination is logically impossible. It is now plain that, unless all positive properties be compatible with each other, this phrase [i.e., "a being than which none greater can be imagined"] is just meaningless verbiage like the phrase “the greatest possible integer.”

God’s Awesomely Contradictive Properties

An odd aspect of Anselm’s argument is that it was originally addressed not to humans but to God himself, in the form of prayer (you’d think that any entity capable of listening to prayer would need no convincing of his own existence).

There are a number of plausible arguments for thinking that even this restricted set of properties is logically inconsistent. For example, moral perfection is thought to entail being both perfectly merciful and perfectly just. But these two properties seem to contradict each other. To be perfectly just is always to give every person exactly what she deserves. But to be perfectly merciful is to give at least some persons less punishment than they deserve. If so, then a being cannot be perfectly just and perfectly merciful. Thus, if moral perfection entails, as seems reasonable, being perfectly just and merciful, then the concept of moral perfection is inconsistent.

The problem of divine foreknowledge can also be seen as denying that omniscience, omnipotence, and moral perfection constitute a coherent set. Roughly put, the problem ofdivine foreknowledge is as follows:

[6] If God is omniscient, then God knows what every person will do at every moment t. To say that a person p has free will is to say that there is at least one moment t at which p does A but could have done other than A. But if a person p who does A at t has the ability to do other than A at t, then it follows that p has the ability to bring it about that an omniscient God has a false belief – and this is clearly impossible.

Ontological Argument from the Playground

If I may, I’d like to provide an alternative version of the a priori Ontological Argument that I am borrowing from the God Delusion where he translates the argument into the “appropriate” language of the playground [7]:

“Bet you I can prove God exists.”

“Bet you can’t.”

“Right then, imagine the most perfect perfect perfect thing possible.”

“Okay, now what?”

“Now, is that perfect perfect thing real? Does it exist?”

“No, it’s only in my mind.”

“But if it was real it would be even more perfect, because a really really perfect thing would have to be better than a silly old imaginary thing. So I’ve proved that God exists. Nur Nurny Nur Nur. All atheists are fools.”

The idea that such conclusions could be drawn from such semantic word play personally offends me. Is there anything we can think of that by the mere fact that we can think of it, is shown to exist outside of our thought? If the answer is yes then might we need to conclude that there lies a bridge from pure thought to things. Rational thought would be suspicious of any line of reasoning that reached such a conclusion without any empirical a posteriori data.

Ontological Parody

The most definitive refutation of the Ontological Argument were by Immanuel Kant in which he identified the card up Anselm’s sleeve in his assumption that existence is more perfect than non-existence. The American Philosopher Norman Malcolm put it like this “The doctrine that existence is perfection is remarkably queer. It makes sense and is true to say that my future will be a better one if it insulated, rather than not-insulated; but what could it mean to say that it will be a better house if it exists than if it does not?”

The Australian philosopher Douglas Gasking devised this ironic parody of the Ontological Argument [7]:

1. The creation of the world is the most marvelous achievement imaginable.

2. The merit of an achievement is the product of (a) its intrinsic quality, and (b) the ability of its creator.

3. The greater the disability (or handicap) of the creator, the more impressive the achievement.

4. The most formidable handicap for a creator would be non-existence.

5. Therefore if we suppose that the universe is the product of an existent creator we can conceive a greater being namely, one who created everything while not existing.

6. An existing God therefore would not be a being greater than which a greater cannot be conceived because an even more formidable and incredible creator would be a God which did not exist.

7. Therefore, God does not exist.

Needless to say Gasking did not prove that God does not exist any more or less than the Ontological Argument proves otherwise.











A Priori Arguments
I accept the Anselmian definition of god. However, we’re not debating Anselm’s formulation of the ontological argument.

Thomas Aquinas misunderstood the argument. You don’t have to argue that you know everything about the essence of god. You just have to argue that you know god would have all great-making properties to the maximal extent. If I claimed that I fully understood what those great-making properties were, then Saint Aquinas’s criticism would apply. I’m not making such a claim in this debate, however.

Hume says that there is no being who’s non-existence does not imply a contradiction. I think that can be disproved. Imagine a being called ‘X’’ that is an objective feature of all reality. It exists in all possible worlds. Because of that, it would entail a contradiction for that being not to exist. We can conceive of a being who’s non-existence entails a contradiction, so Hume was incorrect.

The X, Y, and Z trait argument makes an assumption that is biased towards the person who rejects the ontological argument. It assumes that there is no being that can exemplify all three traits. It only begs the question: why is there a being that can’t exemplify all three?

God’s Justice and God’s Mercy
Con argues that god’s maximal justness and god’s maximal mercy entail a contradiction. I’ll quote from Gregory Koukl to show that there is no contradiction. (Hey, Con got to quote, too!)

‘’Jesus told a parable in Matthew 20 about laborers who were hired at different times in the day, but when the day was over, were all paid the same wage whether they worked all day or only a portion of it. One of the men who had worked all day long complained. Jesus' response was, "Friend, I am doing you no wrong; did you not agree with me for a denarius? Take what is yours and go your way, but I wish to give to this last man the same as to you. Is it not lawful for me to do what I wish with what is my own?" There was no injustice here because there was no obligation to pay all men equally, only an obligation to pay what was agreed on.

A mother has an obligation to her children, for example, that she does not have to the children of her neighbor. If she gave food to her own children but not to the kids next door, no one would call her unjust or unfair. If she chose to do so she, would be considered gracious, but no one would suggest that she was obliged to do so.

And now we've introduced another word into the discussion that is very important: graciousness, or simply, grace. Grace involves the giving of something that is not required (required giving would be called obligation) motivated by the heart of the one giving, not by the worthiness of the one receiving. We say, "That was a gracious gesture," because it was something that was not deserved or required; it was something beyond what was necessary.

Jesus' little parable says volumes about the question at hand. It says that since gracious giving is not obliged but a choice, God is not obliged to extend grace to everyone equally. If He chooses to extend forgiveness to some and not to others (and please note that I'm not arguing that He did, but if He did) He would be neither unfair or unjust because, to paraphrase Jesus, is it not lawful for Him to do what He wishes with what is His own? If you cancel one of your debts, are you obliged to cancel all of them? I suspect not, and neither is God.

So God is not constrained by His grace. Grace is not an obligation, by its very definition and by its very nature. And if there is no obligation then there is no responsibility for God to make it available to everyone. "I will have mercy on whom I will have mercy," He says.

God has no obligation to pardon, then, and this is not a violation of justice or fairness. But if God is just, then He does have an obligation to punish the guilty and an obligation not to punish the innocent. A violation of either would be injustice. God cannot merely let the guilty go free, and He can by no means punish the innocent.

And this, incidentally, is not good news; its bad news, because the other thing God says about this situation--and one that we're all aware of in our more honest moments--is that we are not innocent, we're guilty.

Whether God has made forgiveness available to everyone or not is another issue, and I don't want to address that here. But I want you to be clear on one thing: God owes no one forgiveness, but He does owe them punishment, if they break His law--and that's all of us. Those who are finally condemned will have received justice; those who are finally saved will have received grace, which they did not deserve.’’


God’s Foreknowledge and Free Will
The problem of theistic fatalism argues that since God knows everything, he will know what we do next, so we can’t be free agents. This problem is only superficially convincing. It turns out that the problem misunderstands what it means to be omniscient. Omniscience is the trait of knowing anything that is logically possible to know [1]. It is not the trait of knowing everything. Since it’s logically impossible to know the future actions of free agents*, it is not possible for god to know what we will do next. Ergo, omniscience and free will are reconcilable.

*If that were the case, then it would be pre-determined, and you wouldn’t be dealing with a free agent.


Kant’s Objection: Existence is not a predicate
Kant was right to point out that existence isn’t a property. Rather, it’s something required for you to give properties to something. But, the modal ontological argument doesn’t require existence to be a property. It only requires necessary existence to be a property. [1]

Why is existence greater than non-existence? It's clearly greater to exist than not since if you didn't exist, there would be ~you and so nothing great could arise in which you're the only existing entity whatever.

In fact, it may even be nonsense to say that non-existence is greater... how would that work out? If nothing is not anything, and since only things have the capacity for greatness, however big or small, then how in the logical world can ~thing be somehow "great"? [2]


The Gasking Objection

P5 of Gasking’s objection is logically incoherent. There exists no logical state of affairs which contains a non-existent being which creates the world. You can’t create the world if you don’t exist, because non-existent beings have no casual properties.

P6 is also unsound. It is impossible for a being that does not exist to be greater than a being that does exist. A being that doesn’t exist has no properties, therefore, it can’t have any great-making properties. From that, a non-existent being can ever be greater than an existing being.


Debate Round No. 2


Wishful Thinking - The Poverty of a priori Thinking

Thomas Aquinas did not misunderstand the argument any more than Plantinga. He simply wasn’t as semantically clever in his intentions. My section in R2 regarding a priori thinking was to set up my forthcoming argument supporting a lack of reason and the qualitative abundance of assumptions in any Ontological Argument and how a priori reasoning is not pragmatically valid for knowing the nature of God (as Aquinas would say) let alone knowing the nature of reality.

Changing God’s properties

To bolster his argument Pro has decided to manipulate(a common theological practice) God’s properties to better fit his interpretation of the Ontological Argument which itself has undergone it’s own numerous manipulations, which incidentally has over a seemingly never ending loop of changes for once again, bolstering intentions. Pro softens God’s mercy by removing the debt of responsibility that is endorsed and that the religiously faithful are coerced into aspiring. It’s not particularly nonsensical to make changes to an experiment if one were to have ambitions to use a scientific method to support a shaky theory; but doing so with un-empirical/a priori data to support a semantic word game that alters the original hypothesis is hardly scientific or reasonable.

and regarding foreknowledge...

[1] If an omniscient entity could always "know" how to create new information it doesn't already know, it's never "omniscient", and never will be or could be. This becomes a problem of infinite regress that invalidates the premise of being "omniscient". It even invalidates "omnipotence" because it could never make itself "omniscient" if it could infinitely create new information it doesn't already know. Thus the premises by their nature self collapse, and are regarded in such a paradox as impossible concepts.


The Irony of Parody

Pro is confused about the purpose of including Kant’s objection to Anselm’s deceptive card and Gasking’s parody of the Ontological Argument. It’s presentation is obviously not meant to validate Plantinga’s argument when Gasking displayed it’s compatibility with non-existence, it is meant to trivialize its premise by emphasizing its tautology. Pro clearly quantifies his opinions by rebutting that existence is greater than non-existence (another instance of a priori reasoning, only further tainted by opinionative intention). For whatever intention I cannot practically fathom how Pro could be seduced by a priori’s charm rather than that of empirical data.

The problem with modal logic

Plantinga uses modal logic to bolster the Ontological Argument. I could do no better than to quote Chris Hallquist:

[1] “Now Plantinga is not so crazy as to claim that his argument actually proves the existence of God, or to insist people must grant his assumption that God is possible. Instead, he says that it’s reasonable to believe that it’s possible that God exists, and therefore it’s reasonable to think that God exists. But again, by analogy with mathematics, we can see that this is a silly way to argue.

Imagine two mathematicians, Alice and Bob, arguing over whether it’s reasonable to believe the Goldbach conjecture. Alice argues that the Goldbach conjecture is unproven, and we should not believe unproven mathematical claims. Bob concedes that it is unproven, but says the Goldbach conjecture seems true to him, and it’s reasonable for him to believe it on that basis.

Now, you may agree with Alice here, or you may agree with Bob, but imagine Bob tried to strengthen his position by saying, “Well, surely you agree that it’s at least reasonable for me to believe that the Goldbach conjecture is possibly true. But if I believe the Goldbach conjecture is possibly true, S5 allows me to infer that it is true. So it’s reasonable for me to believe the Goldbach conjecture.” This is a silly argument. Even if you think Bob is reasonable to believe the Goldbach conjecture, this can’t be the reason why.

So, not only does Plantinga’s argument fail to prove the existence of God, it fails even in Plantinga’s stated goal of showing that belief in God is reasonable. Both of those points are totally obvious once you realize that you could give a Plantinga-style argument for any purported necessary truth, in particular truths of mathematics. If Plantinga’s argument had been something tacked to a bulletin board on a graduate student lounge as a joke, it wouldn’t have been bad as academic in-jokes go. But as a serious argument it’s worthless.”

What he seems to be arguing is “hey look, if you take modal logic seriously, you could prove anything in mathematics this way, but that’s absurd.” Chris responds to this by adding:

“Well, no. No absurdities result from merely “taking modal logic seriously.” To get to the point where you can prove anything with modal logic, you have to do a combination of two things: (1) accept S5 and (2) think you can just assume things are possible. I’m okay with (1) and think the problem is with (2). You could also avoid the absurdities by rejecting S5. Either way, it undermines Plantinga’s argument.”


All Minds are Pragmatic Solipsistic Minds

“P3: If a maximally great being exists in some possible world, then it exists in every possible world.”

What a conclusion for Pro to make! Assumptions about any connection between your own mind and others are only valid in a pragmatic sense. Making assertions about the absolute is no more than hypothesis. The term "exists" is used for those things which adequately exhibit things which offer brute physical resistance to our movements but absolute existence is impenetrable from attempts to crack its nature by a being with mere sensory data.

Even after all of life’s empirical pragmatism, the only absolute exists in the mind. A lonely solipsistic mind. [1] Solipsism is the philosophical idea that only one's own mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure.

This is not to say that we don’t participate in life pragmatically. We follow the seemingly empirical rules of life like any other seeminly existent mind. Pants, food, walking... all basic actions (traditions?) that we seem to learn instinctively with no problem due to a seeming compatibility with empirical surroundings. We accept these basic truths pragmatically but there’s no reason other than faith to succomb to their fallacies philosophically.

With limited sensory data, the misconnection of minds is most easily understood using an old [2] philosophical question as to whether you see the same red as I do. Maybe your red is my green, or some other color that I cannot imagine. Philosophers cite this question as one that can never be answered and fits into Dawkins realm of Permanent Agnosticism in Practice (PAP) which is something unknown that is permanently inescapable.

However historically astonished pragmatists are when mocking the lonely solipsists cries of the unknown in expounding the social character of consciousness, they remain baffled and can only absolutely accept in good faith any assertions of social consciousness. This view of consciousness (like the PAP color red) is settled forever in the realm of hypothetical subjection as it is unknowable as to whether absolute outer realities ever come within one’s own stream of private consciousness.


What this truly illustrates is not that we are really all solipsistic and not presented with a real version of reality. Rather, it shows the irrationality of concluding that you know any better for non-pragmatic purposes. Between atheists and theologians it is impossible to know which argument is more valid. Furthermore, the coherence of asserting that an external God exists is no more plausible than any other externally fictitious or real thing unless you rely on practical empirical data for pragmatic purposes, which theologians fail to do in the search for God.



Arguments that Con dropped
- Aquinas’s criticism of Anselm
- X, Y, and Z trait argument
- Foreknowledge and Free will paradox
- Hume’s criticism of a priori reasoning

A Priori
In my last round, I tried to show that Aquinas didn’t fully understand the purpose of the ontological argument. You don’t have to know everything about god. You just have to know that he has all great-making properties to the maximal extent.

Con does not respond to this objection. All we get is a vague criticism of Plantinga using semantics. We’re never given any reason to think that my rebuttal of Aquinas was invalid.

Con also continues to repeat, like a mantra, that A priori reasoning can’t be used. His justification for this was to quote David Hume. But I’ve already responded to Hume! Con never answers to my criticism of Hume, and just repeats that A priori reasoning is invalid by way of bare assertion! I’ll further bolster my criticism of Hume as we wait for Con to give an answer.

Following Plantinga, I think it's plausible to distinguish between strictly logical necessity and broadly logical necessity. If P is necessary in the strictly logical sense, we might say that P is in compliance with the rules of logic, or P is such that its denial entails a contradiction. If Q is necessary in the broadly logical sense, we can say that Q is metaphysically necessary, or that Q exists in all possible worlds. Hume’s claim doesn’t appear to recognize or be sensitive to the latter modality. So, when a theist affirms that God is a necessary being, he is not affirming that God is necessary in the strictly logical sense, or that denying His existence entails a contradiction. Rather, he is affirming that He is necessary in the broadly logical sense, or that He exists in all possible worlds. A being can exist in all possible worlds and yet be such that denying its existence doesn’t entail a contradiction.

Omniscience and Omnipotence

Since Con dropped his last paradox, he tries to set up a new one, this time using omniscience and omnipotence to show that god’s nature is contradictory. If god could create new information that he doesn’t already know, then he’s not omniscient because he doesn’t know everything. Like Con’s last paradox, this is easy to solve.

Omniscience is the ability to know everything that is logically possible to know. God couldn’t know information that doesn’t exist yet, because it’s not logically possible to know that*. When god uses his omnipotence to create new information, god just has to know the information the moment it’s created. Because he’s omniscient, he would know the information the moment it’s created. That’s how you reconcile omnipotence with omniscience.

*If you knew of information that didn’t exist, it would have to exist.

God’s Mercy and God’s Justice
Con’s response is to argue, by way of bare assertion, that I’m manipulating the properties of god to fit the ontological argument. We’re never given any reason to think that I’ve done such a thing. Besides, this is just a personal attack rather than a criticism of the argument.

Other than this, we just see Con repeat that A priori reasoning is invalid. Nowhere do we any criticism of my attempt to reconcile maximal mercy with maximal justice.

Kant’s and Gasking’s Objection

If you are going to parody the logic of an argument, then you have to accurately mirror the logic of that argument in order for it to work. Otherwise, you’re not actually parodying the argument. Gasking’s parody fails because it doesn’t have anything to do with the logic of the ontological argument beyond the superficial. Con doesn’t respond to my criticism of Gasking’s argument because he says that it was meant to be a parody. But even as a parody, it doesn’t work.

Con never answers to my criticism of Kant as well. He just says that I use A priori reasoning, which he’s already debunked. As I pointed out earlier, Con hasn’t responded to my criticism of Hume yet. How can he say that A priori reasoning has been debunked as a valid method of reasoning?

Hallquist’s Criticism
Hallquist is just setting up a straw man. The ontological argument doesn’t say that if something is possible, it must actually exist. It argues that, if a MGB is possible, then it must exist. It can only be applied to a being that exists in all possible worlds, if it exists. It does not apply to anything you can think of, like a conjecture or Leprechauns

We have good reasons to think that solipsism isn’t true, however. If everything is the product of the solipsists mind, then all information would be the product of the solipsists mind. If all information were the product of the solipsists mind, then the solipsist couldn’t learn any new information. However, the solipsist does learn new information every day. Therefore, not everything is the product of the solipsists mind!

Anyways, P3 is logically valid. A maximally great being, in order to be maximally great, would have to exist in all possible worlds. There’s nothing controversial about saying this. The only way to refute P3 is to show there is no possible world a maximally great being exists, which Con hasn’t done.

Debate Round No. 3


A priori again

Pro attempts to undermine my a priori argument (which contradictory to his claim that it does not address his objections to Aquinas, the XYZ argument or Hume’s objections) but I humbly attest that I have sufficiently dealt with his objections. Let me put it to you this way:

The expression 'a priori' does not indicate with sufficiently the full meaning (or truth) of our question. For it has been customary to say, even of much knowledge that is derived from empirical sources, that we have it or are capable of having it a priori, meaning that we do not derive it immediately from experience, but from some universal rule (a rule which is itself borrowed by us from experience). Thus we would say of a man who undermined the foundations of his house, that he might have known a priori that it would fall and that he doesn’t have to wait for the experience of its actual falling. But still he could not know this completely a priori. For he had first to learn through experience that bodies are heavy, and therefore fall when their supports are withdrawn.

In what follows we shall understand by a priori knowledge, not knowledge independent of this or that experience, but knowledge absolutely independent of all experience. Opposed to it is empirical knowledge, which is knowledge possible only a posteriori, that is, through experience. A priori modes of knowledge are entitled pure when there is no addition of anything empirical. So, for instance, the proposition, 'every alteration has its cause', while an a priori proposition, is not a pure proposition, because alteration is a concept which can be derived only from experience.

We must distinguish between pure and empirical knowledge. Experience shows us that a thing is this, but not that it can’t be something else. So if we have a proposition that’s thought of as necessary, then it’s an a priori judgment; otherwise, it is not derived from any proposition except one that also has the validity of a necessary judgment, it is an absolute a priori judgment, which Plantinga insistently depends on and passes as given in P1.

The Fine Tuning of Morality

By fine tuning I mean changing properties, characteristics or any parts of the instigative premise of the debate. In highlighting Pro’s accusation of my ‘dropping’ God’s contradictory properties I meant to be implicit by showing that even though we had agreed about what those traits would be in the instigation phase of this debate he was willing to manipulate God’s properties by rearranging the furniture. Pro claims that he has never done such a thing but I leave it to the voters to decide for themselves.

Speaking of fine tuning, “a maximally great being, in order to be maximally great, would have to exist in all possible worlds" - is nonsense and is not part of the definition of maximally great.


Plantinga describes "maximally excellent" as necessarily including the three omni's: benevolence, potence, knowledge. If this being enjoys maximal excellence in all possible worlds, then this being is "maximally great." Plantinga wishes to establish P3 by establishing that a maximally great being exists in at least one possible world. So, without a doubt P3 begs the question. One only has the epistemic right to accept the premise if one understands the nested modal operators, and that if one understands them within the system S5 (without which the argument fails) then one understands that "possibly necessarily" is in essence the same as "necessarily".Thus the premise is invalid because the conclusion is embedded within it.

It follows that Plantinga defines possible world as a logical state of affairs. So, if we presume that a maximally great being would have the power to cause itself to stop existing, then there is a possible world where it has done so, and in that world a maximally great being does not exist.

Along with this, I’ve provided sufficient examples of how impractical it is to use a priori knowledge to make absolute assertions about outer realities when all realities (or possible worlds) are indeed private.

Final thoughts

I’ve thoroughly enjoyed this debate and I’d like to thank my opponent. He is obviously well versed in the language of this argument.

With that in mind I’d like to remind the voters that the burden of proof does lie with Pro and as such we look forward to hearing about how a priori knowledge can truly reveal anything more than a priori data independent of experience.


Ave! I think it's rude to give counter-arguments in the last round, because your opponent never gets to answer them for the debate. So instead of giving a direct point-by point response to the last round, I'm going to advocate for a Pro vote in this debate.

Why you should vote Pro
Con gave several reasons as to why the ontological argument doesn't prove the existence of god. Here is my cumulative list of these reasons.

(1) Aquanis's response to Anselm.
(2) Hume's criticism of a priori aguments.
(3) The 'X, Y, and Z traits' argument
(4) God's maximal mercy v.s. God's maximal justice
(5) The problem of Foreknowledge and Free Will
(6) Gasking's Parody
(7) Omniscient v.s creating new information
(8) Kant's Objection
(9) Hallquist's Objection
(10) Solipsism objection

I've bolded the arguments that Con completely dropped during the debate. This leaves us with three objections to the ontological argument, all of which I gave objections to. Let's consider my responses to those arguments.

Hume's Criticism
I had two objections to Hume.

(1) There is a being that entails a contradiction not to exist, contrary to his claims.
(2) A being can exist in all possible worlds and yet be such that denying its existence doesn’t entail a contradiction.

Con didn't answer these until his last round. Even then, he really didn't answer them. He just made a positive (this is why Hume was right) argument rather than a negative (this is why Pro is wrong) argument. So, my two principle objections to Hume were never satisfactorily answered.

Kant's Objection
I had two objections to Kant.

(1) Existence is not assumed to be a property with the modal ontological argument.
(2) From 1, Kant's criticism is irrelevant.

Con's response to this was to argue that I'm using A priori reasoning, which he showed to be invalid. I think the voters should decide whether Con upheld Hume's criticism. To me, the answer is 'no'.

Gasking's Parody
I had three objections to Gasking's parody.

(1) P5 is unsound.
(2) P6 is unsound.
(3) It does not even work as a parody.

All three of these went untouched by Con.

Con gave a myriad of objections to Plantinga's argument. I commend him for bringing up such a large variety of interesting and challenging objections. The problem is that he was too eager to drop the objections after I responded to them. This is why I believe a Pro vote is most justified.

Aside from that, I sincerely congratulate Con on an awesome and scintillating discussion. I hope to see him around more!

Debate Round No. 4
11 comments have been posted on this debate. Showing 1 through 10 records.
Posted by rottingroom 4 years ago
yes philo, and your single vote made me lose :(
Posted by philochristos 4 years ago
What a shame this debate didn't get more votes. It was a good debate.
Posted by AlbinoBunny 5 years ago
"Hume says that there is no being who"s non-existence does not imply a contradiction. I think that can be disproved. Imagine a being called "X"" that is an objective feature of all reality. It exists in all possible worlds. Because of that, it would entail a contradiction for that being not to exist. We can conceive of a being who"s non-existence entails a contradiction, so Hume was incorrect."

You can imagine a being that has to exist, but you don't know why, you just know it has to. So a being such as that must exist? Why? Because you can imagine it? Funny that doesn't work for me. But then that's what your other "ontological argument" is based on as well, and I don't agree with that either.
Posted by rottingroom 5 years ago
my last sentence btw.
Posted by rottingroom 5 years ago
pro, the last sentence of R4 was basically a dare. I feel let down :(
Posted by toolpot462 5 years ago
Or maybe not.. I just assumed since he'd be Pro it'd be that way before I saw this: "R1. Acceptance and state Ontological Argument."
Posted by toolpot462 5 years ago
He'd have to provide an argument if he starts.
Posted by philochristos 5 years ago
Typhlochactas, why don't you just accept it now and ask rottingroom to delay his opening as long as he can to buy you some time?
Posted by Typhlochactas 5 years ago
I still have to give a final rebuttal on a different debate, so if anyone accepts before I can, I will challenge you later.
Posted by rottingroom 5 years ago
Will do.
1 votes has been placed for this debate.
Vote Placed by philochristos 5 years ago
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Total points awarded:03 
Reasons for voting decision: There were a lot of issues in this debate, so I can't comment on each argument. I'll hit the high points. Con attempted to attack the ontological argument in two ways: (1) by making 'in principle' arguments, and (2) by attacking the first premise. Pro responded adequately to all of the 'in principle' arguments (i.e. arguments against a priori reasoning, etc.), and Con dropped most of those objections. The debate ended up coming down to Con's arguments against the first premise. He attempted to show that a maximally great being is logically impossible, which if true would mean there is no possible world in which a MGB exists. Pro responded the knowledge paradox using the open theism response. Although I disagree with open theism, the response does work, and it works without having to redefine "omniscience." The Gasking objection doesn't work because, as Pro pointed out, there is an incoherence built into the parody whereas no such incoherence exists in the OA. Good debate!