The Ontological Argument of St. Anselm

[ExLuxLucis]

Hello all,

Does anyone know of ways in which the ontological argument can be rebutted (and how those rebuttals can be replied?)

For those of us unfamiliar with it, it was created by St. Anselm, an Italian Archbishop of Canterbury. It attempts to prove the existence of God using pure logic, and runs something like this (and kindly correct me if I get it wrong)

1. God is defined as the “Greater-than-Which-Cannot-Be-Conceived”. This speaks of intellectual conception of God, the atheist who doesn’t believe in the existence of God can still entertain the intellectual concept of God as such a being in his mind.
2. **Beings which are conceived and possess existence are greater than those which are merely conceived. **
3. But this being can be conceived to exist in reality. That is, we can conceive of a circumstance in which God is real, even if we do not believe that this is true.
4. **But it is greater for a being to exist in reality than for it to exist in one’s conception alone. Hence we seem forced to conclude that a being than which none greater can be conceived can be conceived to be greater than it is. **
5. And this contradicts the starting-point, that God exists only in understanding, for that premise led to this conclusion.
6. And therefore God must exist in both understanding and reality.

 

[danserr]

I’m not sure about the ontological argument myself, but I would suggest not relying on Anselm’s version. The most sophisticated version today is the one developed by the University of Notre Dame Philosopher Alvin Plantinga. (A brief, accessible form of which may be found in WL Craigs’s “Reasonable Faith” 3rd edition, p.183-189).

It runs like this:

1). It is possible that a maximally great being exists. (This premise assumes the concept of God is coherant, that it does not entail a contradiction).
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 exits 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.

Among philosophers, premises 2-5 are relatively uncontroversial, The main question is with the first premise. Still, it is pretty cool, that the argument can at least show that if God’s existence is at least possible, then he exists.

The main pop. objection i think you hear, is for people to claim such an argument could also show that a maximally excellent pizza, or island exists, or that a unicorn exists. Even though i’m not totally sure about the argument myself, those objections seem weak to me. A maximally excellent pizza or island is an incoherent concept (and depends on personal preference anyway, so can’t be maximally excellent), while the argument assumes the concept God is a coherent one. Regarding the unicorn, it would not be maximally excellent and so not exist in every possible world, and so not necessarily exist in this one.

For me, the main question is how do we justify premise one, that it’s possible that God exists. I agree that the concept of God is a coherent one, so that helps, but I’m not sure if that’s enough or not.

 

[ExLuxLucis]

Yes, yes, it does seem much more complete. Thanks for that!

 

[Charlemagne_II]

Aquinas rejected St. Anselm’s proof on the grounds that the conclusion is only to be drawn that this being of which no being greater can be conceived exist in the mind, not in reality.

The mathematician Kurt Godel also offered an interesting interpretation of Anselm but did not reveal his interpretation until 1970 when he was approaching death. He anticipates Plantinga’s later version by concluding that “IF it is possible for a rational omniscient being to exist THEN necessarily a rational omniscient being exists.”

I don’t find this argument convincing. How much different would this be from saying: “If it is possible that Santa Claus exists, then Santa Claus must exist”? The atheist could reply, “Since it is not possible that Santa Claus exists, then Santa Claus does not exist.” On the other hand, the atheist cannot say, “It is not possible that God exists” unless he reduces God to the class of beings that includes Santa Claus. Santa, if he exists, has to be a physically real (if elusive) being who bring gifts to children.

But the idea of God (even if elusive) does not even pretend to be knowable as a physical being one might observe through a telescope or a microscope. Even so, the atheist might retort, there is no conclusive evidence that God is anything more than a fantasy. Yet the atheist cannot be certain of this either, since some beings might exist without the possibility of detecting them in a conclusive way. Atheists admit this when they speculate about the existence of other universes existing simultaneously with ours, one of which may have spawned our own universe. This willingness to believe in sister universes rather than God says a lot about atheism. Namely, that it cannot abide the idea of God and will reach out for any possibility other than God to explain the ultimate questions. Not that any ultimate question is ever really explained by the existence of other universes. For example, why should any other universe give birth to our own? There is no reason to do so for the atheist, since every universe must be without plan or purpose.

 

[The_Exodus]

Modal and ontological proofs fail because they don’t depend on experience, but merely function as a priori categories or “metaphysical imaginings” that don’t latch onto anything real, since they are void of a posteriori represenation from experience.

The quickest way to rebut Anselms argument is to say that, all it proves is that, God necessarily exists, if he exists. Neither Anselm nor any modal/ontological/Plantigean argument can get you one step closer than that. Furthermore, unless some other method is adopted, the “if” will remain forever in question.

 

[danserr]

I think that both of your objections are mistaken for a couple reasons.

First, Charlemagne, you ask how this is different from saying "if it is possible santa claus exists, then he exists. That is comparable to the objections I anticipate above about a unicorn or a maximally excellent pizza. Santa Claus is not a necessary being. This means he does not exist in every possible world. If he does not exist in every possible world, then he does not necessarily exist in this one. It may even be that the concept of Santa Claus is incoherent, which would mean that he does not exist in every possible world. God, on the other hand, as a maximally excellent being, would have to exist in every possible world and therefore in this one.

Second, The Exodus you say “The quickest way to rebut Anselms argument is to say that, all it proves is that, God necessarily exists, if he exists.”
This isn’t really the case if you look at the argument. It all depends on the first premise, “It is possible that a maximally excellent being exists.” What the argument really shows is that if it is possible that a maximally excellent being (God) to exist, then it logically follows that he exists. I think that by itself is a pretty impressive accomplishment by that argument.

 

[The_Exodus]

This isn’t really the case if you look at the argument. It all depends on the first premise, “It is possible that a maximally excellent being exists.” What the argument really shows is that if it is possible that a maximally excellent being (God) to exist, then it logically follows that he exists.

Yes, but you see, the question still remains, whether or not it IS possible for such a being to exist. No one disputes the definition or idea. It’s the application thereof to reality that is in question, and so no appeal to ontologism will give us an answer found in reality.

 

[ExLuxLucis]

Aquinas rejected St. Anselm’s proof on the grounds that the conclusion is only to be drawn that this being of which no being greater can be conceived exist in the mind, not in reality.

I do not understand Aquinas’ rejection. I thought the purpose of the ontological argument was to prove exactly this, that if God can exist as a concept in the mind he has to exist in reality.

 

[awatkins69]

I would reject Saint Anselm’s version of the argument, since it treats “existence” as what is called a “predicate”. What that means is that it treats “existence” as something you “have”.

 

[stenlis]

Hello all,

Does anyone know of ways in which the ontological argument can be rebutted (and how those rebuttals can be replied?)

For those of us unfamiliar with it, it was created by St. Anselm, an Italian Archbishop of Canterbury. It attempts to prove the existence of God using pure logic, and runs something like this (and kindly correct me if I get it wrong)

1. God is defined as the “Greater-than-Which-Cannot-Be-Conceived”. This speaks of intellectual conception of God, the atheist who doesn’t believe in the existence of God can still entertain the intellectual concept of God as such a being in his mind.
2. **Beings which are conceived and possess existence are greater than those which are merely conceived. **
3. But this being can be conceived to exist in reality. That is, we can conceive of a circumstance in which God is real, even if we do not believe that this is true.
4. **But it is greater for a being to exist in reality than for it to exist in one’s conception alone. Hence we seem forced to conclude that a being than which none greater can be conceived can be conceived to be greater than it is. **
5. And this contradicts the starting-point, that God exists only in understanding, for that premise led to this conclusion.
6. And therefore God must exist in both understanding and reality.

Well, here’s the issues with this argument:

a) You have not defined what is ‘greater’. It might seem intuitive to you but in reality it is not - different people have different opinions on what is ‘greater’ and what is ‘lesser’. The definition is essential for step 2. of your argument.

b) How do you ‘conceive something to exist in reality’ (3)? Conceiving a donut to exist in your mouth in reality does not make it pop out of thin air - despite the fact that having a donut in your mouth in reality would be ‘greater’ than only having it in your imagination. (Try to argue for a “Donut greater than which cannot be conceived”).

c) Because of b) your step 5 does not make sense. Conceiving a god in reality is still just conceiving. It does not make god pop out of thin air.

 

[stenlis]

I’m not sure about the ontological argument myself, but I would suggest not relying on Anselm’s version. The most sophisticated version today is the one developed by the University of Notre Dame Philosopher Alvin Plantinga. (A brief, accessible form of which may be found in WL Craigs’s “Reasonable Faith” 3rd edition, p.183-189).

It runs like this:

1). It is possible that a maximally great being exists. (This premise assumes the concept of God is coherant, that it does not entail a contradiction).
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 exits 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.

Among philosophers, premises 2-5 are relatively uncontroversial, The main question is with the first premise. Still, it is pretty cool, that the argument can at least show that if God’s existence is at least possible, then he exists.

The main pop. objection i think you hear, is for people to claim such an argument could also show that a maximally excellent pizza, or island exists, or that a unicorn exists. Even though i’m not totally sure about the argument myself, those objections seem weak to me. A maximally excellent pizza or island is an incoherent concept (and depends on personal preference anyway, so can’t be maximally excellent), while the argument assumes the concept God is a coherent one. Regarding the unicorn, it would not be maximally excellent and so not exist in every possible world, and so not necessarily exist in this one.

For me, the main question is how do we justify premise one, that it’s possible that God exists. I agree that the concept of God is a coherent one, so that helps, but I’m not sure if that’s enough or not.

All really stands on 1). It is also possible, that it does not exist…

 

[ExLuxLucis]

Well, here’s the issues with this argument:

a) You have not defined what is ‘greater’. It might seem intuitive to you but in reality it is not - different people have different opinions on what is ‘greater’ and what is ‘lesser’. The definition is essential for step 2. of your argument.

b) How do you ‘conceive something to exist in reality’ (3)? Conceiving a donut to exist in your mouth in reality does not make it pop out of thin air - despite the fact that having a donut in your mouth in reality would be ‘greater’ than only having it in your imagination. (Try to argue for a “Donut greater than which cannot be conceived”).

c) Because of b) your step 5 does not make sense. Conceiving a god in reality is still just conceiving. It does not make god pop out of thin air.

a) Perhaps I should rephrase it then. The “Greater-than-which-cannot-be-conceived” refers to a Being that is perfect in every way, in other words maximally excellent. “Excellence” and “maximally” would not be relative, because for such a being to be truly maximally excellent, it has to be maximally excellent to everyone.

b) When you conceive something in reality, you conceive in thought of a circumstance, or world if you like, where such a thing exists in reality, and not just in conception. This reality is within the thought, and you do not create reality as you suggest. The rest of the argument flows from there.

c)Which brings us to your rebuttal “but it is also possible that it does not exist.” This is true, but the onus is on you to prove that it is *impossible *for such a being to exist. You cannot just say that it is possible that it does not exist, for then it is still possible that it does exist.

 

[awatkins69]

All really stands on 1). It is also possible, that it does not exist…

You’re right. It all stands on 1. If we can properly elaborate 1 then the argument is completely sound, save objections to S5 (which isn’t really that controversial).

As for it being possible that it doesn’t exist, as was said above, in this case you have to prove that it is absolutely logically and metaphysically impossible that such a being could not exist.

I think that Plantinga’s argument is the best version of the ontological argument we have. So I have respect for it. However, I do share some of the worries of the opponents about premise 1.

 

[stenlis]

a) Perhaps I should rephrase it then. The “Greater-than-which-cannot-be-conceived” refers to a Being that is perfect in every way, in other words maximally excellent. “Excellence” and “maximally” would not be relative, because for such a being to be truly maximally excellent, it has to be maximally excellent to everyone.

Yes, but what does “excellence” mean? What qualities constitute “excellence” and why?

b) When you conceive something in reality, you conceive in thought of a circumstance, or world if you like, where such a thing exists in reality, and not just in conception. This reality is within the thought, and you do not create reality as you suggest. The rest of the argument flows from there.

So what about the donut? What is the difference between simply imagining a donut in your mouth and imagining a donut in your mouth in reality?

See the crucial part of your response above is “This reality is within the thought”. If you follow the argument from there, you still only get a god in your thought.

c)Which brings us to your rebuttal “but it is also possible that it does not exist.” This is true, but the onus is on you to prove that it is *impossible *for such a being to exist. You cannot just say that it is possible that it does not exist, for then it is still possible that it does exist.

I did not contribute to this thread to convince you that god does not exist. Rather I wanted to show why the ontological argument is unconvincing.

 

[stenlis]

You’re right. It all stands on 1. If we can properly elaborate 1 then the argument is completely sound, save objections to S5 (which isn’t really that controversial).

As for it being possible that it doesn’t exist, as was said above, in this case you have to prove that it is absolutely logically and metaphysically impossible that such a being could not exist.

I think that Plantinga’s argument is the best version of the ontological argument we have. So I have respect for it. However, I do share some of the worries of the opponents about premise 1.

We need to judge arguments on their own merit. This one is unconvincing because the first premise is shady - it’s not enough to argue that something is possible.

It is possible that there are intelligent beings in the Alpha Centauri star system. Does that convince you that they really are there, just because I say it is possible? Can you prove that it is impossible that they are there?

 

[ExLuxLucis]

Yes, but what does “excellence” mean? What qualities constitute “excellence” and why?

Hmmm. Not sure about the excellence bit. You might be right, though I think that excellence is implicitly contained in the definition of the Being, who is so maximally excellent so as to contain all the qualities of excellence desired by all. Whether we perceive such qualities as excellence is a different matter, for I can have a glass bowl and insist it is a plastic cup.

So what about the donut? What is the difference between simply imagining a donut in your mouth and imagining a donut in your mouth in reality?

See the crucial part of your response above is “This reality is within the thought”. If you follow the argument from there, you still only get a god in your thought.

As I understand it (and again I may be wrong) the argument tries to prove that by virtue of these two thoughts being able to be thought simultaneously, God must exist. It does not create a new reality, rather it says that by doing this you have just thought a thought greater than the greatest thought, and this is self-contradictory. Since you conclusion is contradictory therefore, it follows that your premise, that God exists only in understanding is false. To solve the contradiction then, a Greater than the greatest thought must exist, and this Greater is the greatest thought made real.

 

[Charlemagne_II]

In case anybody wants to know, here are the two passages in Aquinas’ Summa Theologica that concern the ontological argument. First, his formulation of the argument, then his rebuttal.

Objection 2: Further, those things are said to be self-evident which are known as soon as the terms are known, which the Philosopher (1 Poster. iii) says is true of the first principles of demonstration. Thus, when the nature of a whole and of a part is known, it is at once recognized that every whole is greater than its part. But as soon as the signification of the word “God” is understood, it is at once seen that God exists. For by this word is signified that thing than which nothing greater can be conceived. But that which exists actually and mentally is greater than that which exists only mentally. Therefore, since as soon as the word “God” is understood it exists mentally, it also follows that it exists actually. Therefore the proposition “God exists” is self-evident.

Reply to Objection 2: Perhaps not everyone who hears this word “God” understands it to signify something than which nothing greater can be thought, seeing that some have believed God to be a body. Yet, granted that everyone understands that by this word “God” is signified something than which nothing greater can be thought, nevertheless, it does not therefore follow that he understands that what the word signifies exists actually, but only that it exists mentally. Nor can it be argued that it actually exists, unless it be admitted that there actually exists something than which nothing greater can be thought; and this precisely is not admitted by those who hold that God does not exist.

 

[danserr]

Here’s the version, I mentioned earlier just for reference,

1). It is possible that a maximally great being exists. (This premise assumes the concept of God is coherant, that it does not entail a contradiction).
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 exits 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

Most people seem willing to grant that premise one is the key one, that is, if it is possible that God exists, then he exists. (This would not apply to something like a unicorn because a unicorn would not be a necessary being and so not exist in every possible world and so not necessarily exist in this one).

So the question is why accept premise 1, that is is possible that a maximally excellent being exist.
a). First, because it is a coherent idea. There is no contradiction involved in saying that a maximally excellent being exists. (It’s not like saying that a square circle exists). This seems to justify us in believing that it is at least possible that God exists. The skeptic would have to show the notion of a maximally excellent being is somehow incoherent.

b). Other arguments. Maybe there is another argument for belief, for example a cosmological argument, that we think has some force. Maybe it is enough to make us think it is possible that God exists and then the Ontological argument, once you accept that the existence of God is possible, allows the rational inference that God exists.

Does this allow us to consider the argument as having some force?

 

[R_Daneel]

Here’s the version, I mentioned earlier just for reference,

1). It is possible that a maximally great being exists. (This premise assumes the concept of God is coherant, that it does not entail a contradiction).
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 exits 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

Most people seem willing to grant that premise one is the key one, that is, if it is possible that God exists, then he exists. (This would not apply to something like a unicorn because a unicorn would not be a necessary being and so not exist in every possible world and so not necessarily exist in this one).

So the question is why accept premise 1, that is is possible that a maximally excellent being exist.
a). First, because it is a coherent idea. There is no contradiction involved in saying that a maximally excellent being exists. (It’s not like saying that a square circle exists). This seems to justify us in believing that it is at least possible that God exists. The skeptic would have to show the notion of a maximally excellent being is somehow incoherent.

b). Other arguments. Maybe there is another argument for belief, for example a cosmological argument, that we think has some force. Maybe it is enough to make us think it is possible that God exists and then the Ontological argument, once you accept that the existence of God is possible, allows the rational inference that God exists.

Does this allow us to consider the argument as having some force?

No, it does not. There are several reasons.

(1) Number one is incoherent. Not because it is “self-contradictory”, rather because it is meaningless. First the concept of “greatness” is undefined and undefinable in the general sense. The concept of greatness cannot be meaningfully defined even for a specific entity, like “dinner”. The idea of a “maximally great dinner” is a subjective evaluation of something that can be defined (dinner), but different beings will define a “great dinner” differently (think of strict vegetarians and avid meat-eaters).

(2) For such a generic entity as the “being” there is no way to even define “greatness”. No matter how one defines greatness, it is a composite attribute. Different people will consider different “sub-attributes” as a “proper” definition of greatness. For example, I would say that a maximally great being could decide to switch off and on its own existence at will. If it so chooses, it could cease to exist, and then later, it could bring itself back from nonexistence. Or it could create logically contradictory events at will. Surely such a being is much greater than the usual, “garden-variety God” of Christinity.

(3) Even if greatness could be somehow defined to everyone’s satisfaction, it is not clear that all the different sub-attributes can manifest themselves in the same “being”. Some attributes may be mutually exclusive. Which is the greatest “entertainer”, the greatest possible actor, the greatest possible ballet-dancer, the fastest possible runner or the best possible quarterback?

(4) The argument number 3) is just a word-game. It rests on the concept of “necessary” being, which is simply nonsensical. To show that there is a “necessary” being, one must examine all the possible worlds, then prove that in all the possible worlds there is at least one entity, which is part of all the possible worlds. Plantinga’s trickery that if something is “possibly necessary” then it is “necessary” only earns a resounding DUH! If something would exist necessarily, then it would be possible. The concept of “necessary” but “impossible” combination is simply an oxymoron.

This argument comes up every couple of months. Every time it is refuted. Yet it does not die out. Shame, shame!

 

[danserr]

R. Daneel, I am somewhat of a skeptic on the argument as I’ve said earlier because of my concern about the warrant for premise one. But I do not think the objections that you propose are particularly strong ones.

1). You suggest that one problem is premise one (which is the key premise anyway), is that the notion is incoherent because it is subjective and propose the example of a maximally excellent dinner. You are correct that a maximally excellent dinner is incoherent, because it is subjective. But here is nothing subjective about the idea of a maximally excellent being. Such a being is morally perfect, omnipotent, metaphysically necessary, omniscient etc. All these terms have clear, objective meanings. There is nothing subjective about any of this. For the skeptic to be successful, he must show that the existence of such a being is incoherent, but so far, you have not done so.
2). You suggest that a maximally excellent being should be able to will itself into and out of existence. This is absurd. To will itself into existence from nothing would mean that it would have to exist prior to itself, which is metaphysically impossible. The idea you propose is incoherent.
3). There is no reason to think that moral perfection, omnipotence, and omniscience could not manifest themselves in one being. You need to give some reason to think this is the case if you challenge it.
4). I disagree that step 3 of the argument is a word game. It is simply a useful step in laying out very clearly that if it is possible for God to exist, then he exists. Of course premise 3 is obvious. premises 2-5 are all regarded as pretty uncontroversial. Premise one is the kicker.

I do not see that any objection you propose is a convincing reason to doubt the argument.