Explaining the ontological argument

Can somebody explain or give an example of the ontological argument that can’t be replaced with a magic bunny or something else. I’ve heard how strong the argument is “when properly understood” which I take as you aren’t clever enough to understand or agree with the speaker. I want to understand or see a model of the ontological argument that isn’t grounded by the limitations of the human mind (possibility of the greatest possible being being limited or grounded in human made difinitions of a supreme being). Is the ontological argument still considered a strong argument in today’s apologetics?

I never considered it a strong argument. Nor did Aquinas.

It’s a bit of the dog chasing its tail.



You mean the Fourth and Fifth arguments?

The fourth way is taken from the gradation to be found in things. Among beings there are some more and some less good, true, noble and the like. But “more” and “less” are predicated of different things, according as they resemble in their different ways something which is the maximum, as a thing is said to be hotter according as it more nearly resembles that which is hottest; so that there is something which is truest, something best, something noblest and, consequently, something which is uttermost being; for those things that are greatest in truth are greatest in being, as it is written in Metaph. ii. Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum heat, is the cause of all hot things. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.

The fifth way is taken from the governance of the world. We see that things which lack intelligence, such as natural bodies, act for an end, and this is evident from their acting always, or nearly always, in the same way, so as to obtain the best result. Hence it is plain that not fortuitously, but designedly, do they achieve their end. Now whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is shot to its mark by the archer. Therefore some intelligent being exists by whom all natural things are directed to their end; and this being we call God.

I think they are convincing. Of course skeptics may not. Get a copy of Aquinas by Edward Feser. He explains each of the Five Ways pretty well and a lot more besides. You can also follow his Blog Spot here as well and explore his archives too. edwardfeser.blogspot.com/ .



If so, I think the argument is illogical for the simple reason that if God is understood as a being which no greater can be conceived, then Anselm has essentially affirmed his conclusion in a premise. A “being” is an existent thing. This was the accepted idea of “being,” This is my issue even when we accept the assumption that we can derive existence from a conception.

There are also so many other issues with it.

Sorry. I Forgot to answer to your question.

I would say that that is an impossible task. The argument’s foundation is that God is understood (in terms of the being referred to as “God”) to be the one and only one unique being whose essence is that which no greater can be thought.

“God” refers to this being God. “God” (as a concept) must take certain properties which are bounded by human understanding. God cannot be understood apart from this prescribed essence, as his conception purports.

If we could possibly think of God as a being who is not bounded by human understanding, He would have to be an unconditioned reality, whose essence is simply itself. In other words, God would simply be God, period. Nothing more would there be to be understood. But here the attempts to reduce Gods “existence” as we determine “existence” would be futile. In this case, God is a necessary being. His essence assumes and is in fact his existence and we’d be begging the question again.

I don’t often appeal to Bertrand Russell, but existence is not a logicall predicate or property. and is utterly devoid of meaning in a formal system. If this argument were to be valid, we would have to formalize it, which is impossible.

Hello, jmisk,

The so-called “ontological argument” has a number of different versions: the first one being found in St. Anselm’s [Proslogion](“http://www.fordham.edu/halsall/basis/anselm-proslogium.asp#CHAPTER II”), and then subsequently taken up by Descartes and Leibniz.

I don’t consider it a valid argument, frankly, but I think it ought to be critiqued only after understanding it well. Anselm’s is, in my opinion, the strongest of the three versions I know of.

Keep in mind that when Anselm makes his argument he “defines” God in a strictly negative way, as something “greater than which nothing can be thought” (id quo maius cogitari nequit). He considers that his argument is only valid when one uses this negative definition.

The idea is as follows:

*]Everyone–even an atheist–understands what is meant by a “being greater than which nothing can be thought.”
*]This being, therefore, exists in the mind of both believer and atheist.
*]It is greater for something to exist in reality and in the mind, than to exist only in the mind.
*]Let’s suppose, for the sake of argument, that the “being greater than which nothing can be thought” exists only in the mind (not in reality):
*] Then I could think of a a being even greater than the “being greater than which nothing can be thought” (namely, one that exists in reality).
*]However, this is a contradiction. Hence,
*]The “being greater than which nothing can be thought” must exist also in reality.

Substituting something like a “magic bunny” to refute the argument was an idea anticipated by someone called Gaunilo, who postulated an island “more beautiful than which nothing can be thought.” (See the critique by Gaunilo.) Anselm would say that such a concept would fail the first premise: no one is capable of conceiving a island “more beautiful than which nothing can be thought.” (No matter how beautiful the island, you can always conceive of a more beautiful one.)

The concept of the “being greater than which nothing can be thought” is different (Anselm would say): because it is strictly negative, even the atheist can conceive it correctly. He will also see that existing in reality is greater than existing in the mind.

Nonetheless, I still see several flaws. The most important one is in premise #3: It is misleading to say that a thing is “greater” if it exists in both mind and reality, because there is a subtle difference between “existing in the mind” and “existing in reality.” (Not that St. Anselm was deliberately trying to deceive anyone–I just don’t think his logic works.) When we say that something “exists,” without qualification, we are referring to “existence in reality.” Strictly speaking “existence in the mind” is merely hypothetical. If something “exists only in the mind,” strictly speaking, it does not exist at all.

So, in fact, because something exists in reality does not make it “greater;” it simply means that it exists.

In my opinion there is no way to make the argument “work,” because it necessarily starts with the very “concept” of God and tries to deduce its existence (in reality, evidently). But there is never any satisfying way to verify that what is inside your mind corresponds to reality.

That is why, in my view, it is much more satisfying to proof God’s existence based on realities that we are sure exist in reality.

Hi jmisk,

As lmelahn mentions, there are various ontological arguments. The most common objection to these arguments involve parodies, such as Gaunilo’s Island, which fail for the reason lmelahn provides. While few accept Anselm’s version of the argument or Descartes’s, Alvin Plantinga’s version - the modal ontological argument - is perhaps the most hotly debated today. It’s immune to parodies for the same reason Anselm’s argument was and, moreover, the argument is logically valid. So, if the premises are correct, then the conclusion necessarily follows. We might summarize the argument like this:

  1. There is a possible world at which a maximally great being exists. (Premise)

  2. Necessarily, a being a maximally great if and only if it is maximally excellent in all possible worlds. (Premise)

  3. Necessarily, a being is maximally excellent if and only if it is omnipotent, omniscient, and perfectly good. (Premise)

  4. Therefore, an omnipotent, omniscient, and perfectly good being exists. (From 1 - 3 and S5)

The argument is dependent upon the S5 axiom of modal logic, which states in part that whatever is possibly necessary is necessary. Since a maximally great being is possibly necessary, via premises 1 - 3, then in conjunction with S5, it follows that a maximally great being exists. S5 is actually a relatively uncontroversial axiom of modal logic. The reason to accept it is that if a being were possibly necessary, then it would be necessary in at least one possible world w1. Yet, if it didn’t exist in all possible worlds, then it would actually be contingent in w1, which is contradictory.

It turns out that the most (and possibly only) controversial premise of the argument is premise (1)! The best objection to Plantinga’s ontological argument, in my opinion, is to simply restate (1) as (1*): There is a possible world at which a maximally great being does not exist. Then, in conjunction with S5, it follows that a maximally great being does not exist.

One simply has to ask himself whether (1) or (1*) is more plausible. I accept (1) because I also accept other arguments for God’s existence, but on its own, Plantinga’s argument really isn’t a proof either way. Plantinga himself admits this, but maintains that the argument is still rationally acceptable. I’m inclined to agree.

In other words, as Graham Oppy explains in the Stanford article on ontological arguments, an atheist will reject the first premise because he does not believe in a maximally great being, while the theist will support the premise because he does.

Or, to put it somewhat differently, an atheist rejects the OA because he doesn’t believe in God and a theist supports it because he believes in God, but there is nothing in the argument itself that makes one position more rational than the other.

Plantinga says the same thing. One wouldn’t accept the argument’s first premise unless he already accepted the conclusion. Still, there doesn’t seem to be anything irrational in accepting the first premise, which is why Plantinga calls the argument “rationally acceptable,” but not rationally compelling. I would use additional theistic arguments to further support premise (1). On the other hand, Robert Maydole has offered an intriguing argument in support of this premise that doesn’t require anything other than his so-called “modal perfection argument.”

@jmisk and punkforchrist:

I read up up on Plantinga’s argument, and yes, I think he himself would agree that his argument does not actually prove that God exists. It simply establishes that God’s existence is the more plausible option, so to speak.

One of the consequences of the argument is that if God exists (in Plantigna’s language, if there is a possible world in which God exists), then He exists necessarily (i.e., he could not possibly not exist). All the ontological arguments agree on that point.

Their weak point is establishing that in fact God exists.

I think we can do better, however, with a so-called a posteriori argument: an argument in which one starts from a real being and deduces that God is its supreme and ultimate Cause. (I guess I am just an incurable follower of St. Thomas Aquinas in this regard :).)

The advantage of an a posteriori argument is that there is no need to attempt the passage from “possible being” (which, in fact, doesn’t really exist) to real being (which does exist). (Or, in modal terminology, from “possible words” to the real world.) The real being is established from the get-go.

God bless!
Fr. Louis Melahn, L.C.

Fr. Louis, I agree with you completely. Like you, I’m a committed Thomist. :slight_smile:

Substitution examples have never been very good counterexamples to the ontological argument given by Anselm, since the thing in question must be such that there is some reason why necessary existence should be predicated of it.

But no, I don’t think the ontological argument succeeds.

This is a good statement of the argument. Usually it is translated as though Anselm said:

  • Suppose the being greater than which nothing (call it x) can be thought exists only in the mind.
  • Then it would be greater for x to exist also in reality.

ie. Anselm is taken to have been saying that the being exists in the mind, but it would be better for that being to exist in reality. And that, I think, is why people so frequently read the argument and think, “That’s nonsense!” As Elizabeth Anscombe pointed out in her essay “Why Anselm’s Proof in the Proslogion is not an Ontological Argument”, this translation seems to be based off of bad Latin. (On being accused of claiming that Anselm’s proof could be saved by the deletion of a comma, Anscombe replied that she did not think that it was saved, just that it was saved from the stupidity of an ontological argument.) Anselm rather seems to be proposing that one suppose that the being greater than which none can be thought exists in the mind; but then, since we can imagine a being which is greater than that in the mind to exist rather in reality (better in itself, not just because it exists in reality), we have a reductio, and God exists.

But I think that Anselm’s argument, then, does not get us to God’s existence, but rather has a conclusion that is Thomistic in spirit (since Thomas did not think our limited intellects could grasp the divine nature). I think that it is more plausible for us to take 1. and 2. as reduced to absurdity–a being greater than which none can be thought does not exist in the mind, because we can always conceive of a greater one.

When you think about it, by negating the proposition that the being only exists in the mind, we do not get the proposition that the being necessarily exists in both the mind and reality. We get: it is not the case that the “being greater than which nothing can be thought” exists only in the mind (not in reality). And that is consistent with: the “being greater than which nothing can be though” exists in neither the mind nor in reality.

I really prefer Anselm’s argument from gradation in his Monologium. It’s almost identical to Thomas’s fourth way. A simple version might be:

  1. If there are flaws in a thing’s goodness, this can only be known by a standard of supreme goodness. (Premise)

  2. There are flaws in a thing’s goodness. (Premise)

  3. Therefore, there is a standard of supreme goodness. (From 1 and 2)

This isn’t just a moral argument. The goodness mentioned refers not only to moral goodness, but to things that are objectively valuable. The argument has a Platonic spirit to it, and Anselm concludes that God exists as the Supreme Good. Anything that participates in goodness does so because God’s goodness is imbued in it.

Anyway, it’s not my favorite argument, but it’s worth a look.

This formulation is very close to Descartes’ version of the argument. For Descartes, God’s existence forms part of His “definition” in much the same way that a triangle’s definition includes the idea that the sum of its angles is equal to two right angles: hence existence is a “property” or “perfection.” I have the idea of the perfect (hence existent) in my mind; it is clear and distinct; hence (according to Descartes’ theory of knowledge) the reality exists as well.

You are right: Anselm would not have recognized it! Anselm insists on using a reductio ad absurdum.

St. Thomas’ Fourth Way is probably the most rigorous proof for God’s existence, but also the most difficult to understand. And unfortunately, St. Thomas makes only a brief outline in the Summa and expects the reader to fill in the details. It is certainly Platonic (more precisely, Neoplatonic) in flavor, but it relies on concepts that neither Plato nor Aristotle had developed, at least not explicitly.

(In particular, neither Plato, nor Aristotle, nor the pagan Neoplatonists had an adequate understanding of creation.)

I don’t think it is the degrees of perfection that interest St. Thomas so much as the fact that these degrees of perfection are evidence of a participation of creatures in the being (Latin: esse) of the Creator. Or, conversely, it is evidence of God’s communication of his esse to His creatures.

All of the perfections mentioned in the Fourth Way (goodness, truth, nobility) are properties that Thomas calls transcendentia, but that subsequent Scholasticism calls “transcendentals.” They “transcend” the division of being into Aristotle’s ten categories: in other words, they can be properly attributed to any being, although of course their meaning changes according to the type of being. (It is not exactly the same thing to say “God is good” as to say “Charles is good,” or even to say “this pizza is good.” Nevertheless, the meanings are not completely divergent; there is something in common among all of them.)

The important thing here is that the transcendentia are in proportion to what Thomas calls esse (the Latin infinitive for the verb to be). For Thomas esse is not simply “existence,” the mere “fact” that something exists, but is much more profound than that: it is the fundamental act of every being. (What does this rock do? Well, before it does anything, it is.)

This act comes in various intensities, and it is precisely the intensity of the act that explains the differences in goodness, truth, and nobility in the world: a thing is good to the degree that it is, and so on.

As regards a proof for the existence of God, the variability in intensity of goodness, truth, and nobility that we find in the world is evidence of the variability in intensity of esse. This, in turn, indicates that the esse in the world is always limited (otherwise, it couldn’t be any greater than it is). A being with a limited esse does not have the power to communicate its own esse to another being, nor can it give itself its own esse, nor can it be eternal (because limitation is only possible when there is a potential principle in the being, and that potential principle has to be put into act by something outside itself).

It follows that all beings in the world have received their esse directly from Something that is the Source of this esse, that possesses esse as His own (not as received from something else), and that possesses esse in an unlimited way.

We could sum it up like this: “There are all kinds of good/true/noble things in the world. They could, however, always be better/truer/nobler (or worse/less true/less noble). Things are good/true/noble to the degree that they are, hence things in the world possess an intensity of being (esse) that could always, in theory, be greater (or less). Hence, the being (esse) of the things in the world is limited. But being (esse) is a type of act, and acts can only be limited by potencies. Moreover, potencies don’t just become “activated” all by themselves: some other thing in act has to come and activate them. Hence, the things in the world are not the source of their own being (esse). (That is, they participate in the esse of Something else.) The esse of everything in the world must, therefore, be communicated by a (unique) Source that possesses its own esse to an unlimited degree.”

As I said, rigorous, but somewhat difficult to understand. :slight_smile:

Very well put, lmelahn! It’s too bad Richard Dawkins didn’t respond to your rigorous treatment of the argument in The God Delusion. We’ll give him a pass, though, because he’s not a philosopher. :slight_smile:

Many people here will tell you that the argument is invalid, they are taking their cue from Aquinas. Do not take their words as gospel, Aquinas refuted a weak, perhaps the weakest, formulation of the ontological argument. Sadly, too many Catholic see this refutation as being valid across the board with all ontological arguments. Advances in logic have allowed more powerful versions of the argument to be formulated. Leibniz’ and Plantinga’s versions are good examples. The ontological argument is alive and kicking among protestants, you know, people that do not take Aquinas as infallible (a sad belief that I have seen over and over among Catholics).

The ontological argument is an a priori argument, concevaility or being grounded on our definitions of what a perfect being is essential to it. But there are a posteriori arguments that use parts of the ontological argument and do not solely depend on conceivability, for example, many modal cosmological arguments.

As for magic bunnies, perfect islands and so forth that shows that the argument is not being understood by the critic. The argument speaks of the greatest being that can be thought, a maximally great being or an infinite being. is a rabbit or an island the greatest being that can be thought, a maximally great being or an infinite being

But isn’t maximally great subjective? Who defines what a maximally great being would do or be capable of? And if we could somehow argue what the features of God are, how do we use this as a Christian God arguement and not just a deist argument?

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