The Ontological Argument
One of the distinguishing
features of Ontological Arguments is that they are deductive and a
priori. They attempt to prove God's existence by reason alone,
independent of experience. There are many different versions of the
ontological argument, but the general spirit behind all of them is
this: just by contemplating our idea of God—without having to look out
in the world or find any sort of empirical proof—we can come to
conclude that God must exist
We will be looking at Anselm’s
ontological argument(s) in his Proslogium. I argued in class that in
Chapter 2 of the Proslogium, Anselm presents a reductio ad absurdum. He
assumes the opposite of what he aims to prove—i.e., he begins by
assuming that God (the being than which nothing greater can be
conceived) does not exist (in reality). If this assumption leads to a
contradiction or absurdity, then we are justified in rejecting the
original supposition and accepting its contrary—namely, that God does
exist (in reality).
We will also be looking at
Chapter 3 of the Proslogium. In this chapter, Anselm (arguably)
suggests a modal version of the ontological argument, which we will
discuss in tandem with David Lewis’ article “Anselm and
In the pages that follow,
however, I only concentrate on what I take to be Anselm’s argument in
Summary of Argument
Anselm defines God as the
greatest conceivable being, or as something than which nothing greater
can be conceived. To get a grasp on this, take every great-making
attribute you like—wisdom, power, knowledge, moral goodness, etc.—and
amplify these great-making features to their limit. There. Now you've
got God. If you can think of anything greater than what you've just
thought of, then you haven't succeeded in thinking about the thing than
which nothing greater can be conceived.
Of course, just thinking of
such a being does not (yet!) commit you to thinking that such a being
exists (in reality). For consider: even if you think that the greatest
conceivable being (GCB) does not exist, you at least have the ability
to understand or have an idea of such a being. You can, at the very
least, understand what such a being would be like. And this is all the
argument needs to get it going. So long as you can at least understand
the idea of a GCB, the argument aims to show that, on pain of
contradiction, such a being must exist.
If you disagree with Anselm’s
definition here, it won’t matter. For if you understand what Anselm (or
any other theist) means when he talks about the GCB, and you think that
that thing—God defined as such—simply does not exist, then Anselm’s
argument is aimed at you. Anselm’s point (eventually, in order to get
the argument going) is that if you disagree with Anselm, if you claim
“God does not exist”, you must understand what the word ‘God’ means, or
else your claim is meaningless.
In class, I asked whether the
statement “Flugblubs do not exist” is true or false. Since you do not
know what ‘flugblubs’ means—because I made it up specifically to be a
nonsense word—you cannot say one way or the other whether you think
such things exist. As another example, ask yourself whether you agree
with any of the claims made in Lewis Carroll’s Jabberwocky (attached on
the back). If you do not (even minimally!) understand the terms being
used in a sentence, you cannot coherently claim whether such things
exist or not. This is a crucial point, and one that Anselm capitalizes
on in order to generate his reductio.
Existing in the Mind vs.
Existing in Reality
Next, Anselm invokes the
distinction between existing in the mind and existing in reality.
Intuitively, many things can exist in the mind alone without existing
in reality. Unicorns, wizards, the fountain of youth, and Harry Potter
are all things that exist in the mind alone, but do not exist in
reality. In contrast, there might be some things that exist in reality,
but do not exist in the mind. There could be some totally crazy looking
beetle that has not yet been thought of in the minds of men, but
nonetheless exists in the world. So there are some things that exist in
the mind (alone), which need not exist in reality; there are some
things that exist in reality, which need not exist in the mind; there
are some things that exist in the mind and reality (you and me, for
example), and there are some things that do not exist either in the
mind or in reality (but of course we cannot say what they are for as
soon as we do *poof!* they exist in the mind).
Setting Up the Reductio
Let's suppose that the atheist
is right. Let’s assume that the Greatest Conceivable Being (GCB) exists
in the mind alone, but not in reality. This might seem a really
backwards way to the conclusion—after all, this is an argument for the
existence of God, to the conclusion that God exists in reality, as well
as in the mind. But this is the nature of a reductio ad absurdum. One
assumes the contrary of what one is trying to prove in order to show
that a contradiction or absurdity follows. So this argument will start
out assuming that the Greatest Conceivable Being exists in the mind
alone, but not in reality.
Existing in Reality Makes
A crucial premise in Anselm’s
(first) ontological argument is the claim that existing in reality is a
great-making property. Why should we think so? Suppose we have an
imagined beer that exists in the mind alone. Make this pint of beer
anything you like—make it as cold as you like, as bitter or hoppy as
you like, as big as you like, etc.—but make sure that it exists in the
mind alone, and not in reality. Nice, right? But not much good to us,
if we are thirsty for a cold one. So now compare this merely imagined
beer to one that is not only imagined, but exists in reality as well.
Presumably, it is better that the pint of beer exists in reality, as
well as in the mind, rather than the beer existing in the mind alone.
At least, it's pretty clear which one you'd prefer given that you've
got a considerable thirst.
It is important to realize
that the claim is not: anything that exists in reality and in the mind
is greater than anything else that exists only in the mind. Rather
it’s: Take something that exists in the mind. That same thing would be
better if it exists in reality.
(If this seems too quick,
don’t worry. We’ll get into this in more detail after we have formally
laid out the argument.)
Showing an Absurdity Follows
To recapitulate, we have
assumed that the GCB exists in the mind alone, and not in reality. But
we have also agreed that whatever exists in reality, as well as in the
mind, is greater than that same thing that exists in the mind alone.
But now we're in trouble! Because now we can think of a being greater
than the GCB—namely, we can think of a GCB that exists in reality as
well as in the mind. Thus, the GCB—the being than which nothing greater
can be conceived—is a being than which something greater can be
conceived. But this is a contradiction. Therefore, the original
assumption—that the GCB exists in the mind alone—must be false, and
it's contrary must be true. So, the GCB must exist in reality as well
as in the mind. So, God exists (in reality)!
Formalizing the Argument
that the Greatest Conceivable Being (GCB) exists in the mind, but not
in reality. [Let's call him Rod.]
in reality is greater than existence in the mind alone.
3. We can
conceive a GCB that exists in reality as well as in the mind. [Let's
call him Todd]
Therefore, there is a being [Todd] that is greater than the GCB
5. But this
is a contradiction: there cannot be a being greater than the Greatest
Therefore, it is false that the GCB exists in the mind alone and
not in reality.
7. The GCB
at least exists in the mind.
8. So, the
GCB must exist in reality as well. So: GOD EXISTS (in reality)!
Guanilo's Perfect Island
Guanilo suggests that
something has seriously gone awry in the Ontological Argument. To show
this, he devises a similar argument, resulting in a conclusion that we
know to be false. He suggests that we run a parallel argument with one
minor alteration--replace the Greatest Conceivable Being with the
Greatest Conceivable Island. The replacement argument can be formalized
in the following way:
that the Greatest Conceivable Island (GCI) exists in the mind, but not
in reality. [Let's call it Ned.]
in reality is greater than existence in the mind alone.
3. We can
conceive a GCI that exists in reality as well as in the mind. [Let's
call it Maud.]
Therefore, there is a island [Maud] that is greater than the GCI
5. But this
is a contradiction: there cannot be an island greater than the Greatest
Therefore, it is false that the GCI exists in the mind alone and
not in reality.
7. The GCI
at least exists in the mind.
8. So, the
GCI must exist in reality as well. So: the GCI EXISTS (in reality)!
Guanilo's point is that if the
above version of the ontological argument goes through, then we can
reason similarly for the existence of the greatest conceivable island.
What’s more, we can run this kind of argument for the existence of the
greatest conceivable anything-you-like: the greatest conceivable lover,
the greatest conceivable beer, the greatest conceivable evil being,
etc. Yet since it is clear that there is no greatest conceivable island
(lover, beer, evil being, etc.), something is amiss with the argument.
Note: there are two main ways
to refute an argument: (i) attack the form of the argument or (ii)
claim that (at least) one of the premises is false. Guanilo's Perfect
Island Objection is doing the first. Can you see why?
You can read Anselm's response
to Guanilo's objection on-line here:
I admit that I have difficulty
trying to understand his response clearly. Often, Anselm’s response
seems to be nothing more than a mere restatement of his original
argument (and thus not really addressing Guanilo's objection at all).
But he does say the following, which (read charitably) has some
"BUT, you say, it is as if one should suppose an
island in the ocean, which surpasses all lands in its fertility, and
which, because of the difficulty, or the impossibility, of discovering
what does not exist, is called a lost island; and
should say that the be no
doubt that this island truly exists in reality, for this reason, that
one who hears it described easily understands what he hears.
Now I promise confidently that if any man shall
devise anything existing either in reality or in concept alone (except
that than which a greater be conceived) to which he can adapt the
sequence of my reasoning, I will discover that
thing, and will give him his lost island, not to be
lost again.” Anselm’s Apologetic, Chapter III
From the quoted passage above,
we can perhaps tease out the following response: in my original
formulation of the argument, and indeed, given Anselm’s definition of
God, we were considering the greatest conceivable being. But what was
really meant (Anselm might argue) is the greasiest conceivable thing.
When it is left open as to what the greatest conceivable thing is,
there do not have to be limitations on the object under consideration.
But there would be limitations if we needed to qualify the object as a
particular kind of thing or other. If we must conceive of the greatest
conceivable island, for example, then there are certain attributes that
this island must have in order to qualify as an island. It must be
surrounded by ocean on all sides, for instance. Or it may have to have
been formed in a particular way—by a volcano, say—and it must be a land
mass, with sand and rocks, perhaps some coconut trees, or certain
vegetation, or a particular monkey to palm leaf ratio, etc. But the
very qualities that make something an island may conflict with the very
qualities that make something the greatest conceivable thing.
To see this, let’s play the
which one is greater? game.
Which one is greater? An
island that knows some things or an island that doesn't. Clearly, an
island that knew what was going on would be greater than one that
didn't, or couldn't. OK. So now we imagine our island as an island that
knows some stuff.
Which one is greater? An
island that knows everything, or an island that knows only some things.
Clearly, an island that knows everything. OK. So now we imagine our
island as one that knows everything.
Which one is greater? An
island that is benevolent and can do morally good actions, or one that
is morally neutral, or even worse—morally malevolent. Clearly, a
benevolent island is better than a non-benevolent one. OK. So now our
island is morally benevolent.
Which is greater? An island
that is benevolent all of the time and in all ways, or an island the is
benevolent only some of the time and in only some ways. Clearly, the
first. OK. So now our island is omnibenevolent.
And which is greater: an
island that has powers, or one that is inert? Clearly, one that has
power, and lots (if not all) of it. OK. So now our island is
omnipotent. And so on.
After we have played the which
one is greater? game, what we presumably end up with is something more
like a God and less like an island. In fact, we could even ask: Which
is greater? An island that is located in only one spot and not others?
Or an island that can be everywhere all at once? What we'd eventually
end up with is an omnipresent 'island' that is nothing like an island
at all! This is because those qualities that make something great
simpliciter—regardless of what kind of thing it is—are in conflict with
those qualities that make something an island.
Anselm's original argument, in
other words, is a demand for the greatest conceivable thing-whatsoever
or thing-in-general. A greatest conceivable thing-in-particular is
necessarily limited in certain ways—indeed, in all of the ways it has
to be in order to qualify as a particular thing or other. And so a
greatest conceivable thing-in-particular can never be the greatest
And this might be what Anselm
is getting at when he says:
"Now I promise confidently
that if any man shall devise anything existing either in reality or in
concept alone (except that than which a greater be conceived) to which
he can adapt the sequence of my reasoning, I will discover that thing,
and will give him his lost island, not to be lost again." (Emphasis
Anselm seems to be saying: if
you can think of a greatest conceivable thing, and that thing ends up
being an island, then so be it. The island must exist. But, given that
the greatest conceivable thing is probably not an island (for reasons
alluded to by the which one is greater? game), Anselm is confident that
the argument won't deliver us a greatest conceivable island. But it
will deliver the greatest conceivable thing, which is God.
Note: the above proposal is
just my take on Anselm's response, and I am no Anselm scholar.
Nonetheless, the response is available in logical space. I will leave
as a response on Anselm's behalf, even if he did not endorse this move
himself. Do you think the move works? Why or why not?
is Not a Predicate (Kant)
Immanuel Kant objects that
‘existence’ is not a predicate in the way that ‘red’, ‘six feet tall’,
and ‘wacky’ are. If someone says ‘the castle is blue’, the speaker is
attributing a property—blueness—to the castle. Yet when you say ‘the
castle exists’, you are not, strictly speaking, attributing any
property or characteristic to the castle. Rather, you are saying that
the castle is instantiated, or exists in the world, or something to
that effect. In other words, we aren't really adding anything to our
idea of the castle, but to our idea of the world, and the way that it
is—namely, that the world is such that the castle is in it.
To illustrate the above point,
consider the following examples.
a table. Now abstract away all of its properties except existence. That
is, imagine that you could leave it existing without all of its other
properties: color, shape, size, function, and so on. But what is the
difference between existence alone and nothing at all?
2. Marge and
Lisa are both compiling lists of the qualities of the perfect mate so
that they can each put an ad in the personals. Since Marge and Lisa
have similar tastes, they both end up with the following add:
"Intelligent, hot chick in search of good-looking male, with an
affinity for doling out compliments, playing pool til dawn, and talking
philosophy until the cows come home." In fact, the only respect in
which Lisa's ad differs from Marge's is that Lisa has supplemented the
forgoing blurb with the extra qualification: "and must exist." Now, is
Lisa's ad really any better than Marge's? No. Moreover, it seems that
Lisa has misunderstood the purpose if the list, which is to set forth
the qualities of a perfect mate. It is another matter whether these
qualities are exemplified in an actual guy. Marge and Lisa can decide
what they want to put into their description of the perfect guy, but
the world decides (or determines) whether anybody meets such a
3. We cannot
simply build existence into our concept of things, yet it seems we have
no problem doing this with regular predicates. For example, suppose we
define a unicorn as: a one horned magical horse that exists. One might
then claim that unicorns exist. But, of course, this is just a verbal
trick. Nothing but the world can determine whether something fitting
our concepts exists or not, and wishing it doesn't make it so. Contrast
this, however, with regular predicates. If I define "smelloozer" as
someone who drinks heavily and smells funny, then we can
(uncontroversially!) claim that smelloozers drink heavily and smell
funny. So we can build predicates into our definitions, but not
existence. So, existence must not be a predicate.
Be careful! This last point is
not the following objection: we cannot define anything into existence,
yet Anselm does (with his definition of God), so his argument stinks.
This objection is misguided, first, because Anselm does not (in the
version I have proposed) define God as an existent thing. Second, this
objection is aimed at ‘existence’ as a predicate. It is a recognition
that ‘existence’ does not behave in the way that other predicates do,
because it, unlike other (legitimate predicates) cannot be built into
The strategy of this Kantian
objection is to indirectly attack the truth of premise 2. For an
underlying assumption of the truth of premise 2 is that existence is a
predicate like 'blue', 'round' and 'groovy' are. So, unlike Guanilo's
objection, which attacks the form of the Ontological Argument, Kant's
objection attacks the truth of one of the premises (viz., premise 2).
Consider the series of
positive integers: 1, 2, 3, etc. Now suppose I ask you to imagine the
greatest conceivable integer. Rightly so, you should be confused, as it
is quite obvious that the positive integers are not the sort of thing
that admit of a greatest member. That is, for any integer you can think
of, there will always be one greater. (In fact, there will always be
infinitely many integers greater than the one you have in mind.) In
this way, the Greatest Conceivable Integer is an impossible object.
This objection claims that the idea of the Greatest Conceivable Being
is like the idea of the Greatest Conceivable Integer—impossible!
Like Kant's objection, the
strategy of this objection is to undermine the truth of one of the
premises—viz., premise 1. The truth of premise one relies on our
ability to at least conceive or imagine the greatest conceivable being.
But if the Inconceivability Objection is correct, then we cannot
conceive or imagine the Greatest Conceivable Being, and hence, we won't
be able to make the supposition—premise 1—that gets the whole reductio
going in the first place.
Does this objection work? What
then becomes of the atheist’s negative existential claim: God does not
exist? Can one be a coherent atheist of the inconceivability objection
is correct? How?
Reality vs. Existence in the Mind
One problem we might have with
Anselm’s ontological argument has to do with the purported distinction
between existing in reality and existing in the mind. This distinction
suggests that there are two ways for something to exist—in the mind and
in reality. But what sense is there in thinking that a thing exists at
all when it ‘exists in the mind’? Certainly, it isn’t at all
clear how the identity conditions work out for things that exist in the
mind. If I ask two people to imagine a pink elephant, for example, are
the two people imagining the same elephant or not? If a pink elephant
were to run around the corner, would the two people think, “Aha! I see
that the pink elephant that exists in the understanding exists in
reality as well”? Or could one think, “No. That’s not the pink elephant
that exists in my understanding; mine doesn’t exist in reality at
Another example: Suppose that
two artists imagine a painting in their head—such that Anselm would
count the ideas of the painting as things that exist in the
understanding. Is it enough that only one of the artists actually
paints the painting in order for whatever it is that exists in the
understanding to exist in reality as well, resulting in only one
painting? Or would each painter have to paint separately and
individually whatever it is that exists in the understanding before the
painting(s) exists in reality, resulting in two numerically distinct
paintings? Is there any way to tell the difference? If not, it seems we
don’t have a criterion of identity for things that ‘exist in the
understanding’, and so we should be suspicious that this is a
legitimate notion of existence.
Put another way: we know what
it takes for something(s) to be one thing or two when it (they) exist
in reality (note: we will hopefully be spending some time in class
discussing this point, so don't worry for now if it isn't clear to
you). But this isn't the case with things that exist in the mind. For
how are we to know whether the pink elephant that one person
understands and the pink elephant that another understands are one and
the same elephant? Put in terms of Qualitative and Quntitative (or
Numerical identity is the
relation that each thing holds to itself—e.g., I am numerically
identical to myself, you are numerically identical to yourself, Jon
Stewart is identical to himself, etc. If x is numerically identical to
y, then x and y are one in number; "they" are one.
Qualitative identity, on the
other hand, is the relation that many things can have to many others,
provided that they have the same properties in common. For example, in
class I talked about how two markers could have many of the same
properties—e.g., they could both be white on the outside, with a black
felt tip, a black plastic cap, cylindrical in shape, so many inches
long, kept in a cardboard box, etc.—yet since they are two markers they
are not numerically identical. Rather, they merely share some of their
properties, or qualities—they are qualitatively identical—but they are
not one and the same, numerically identical, marker.
How are we to distinguish
between merely qualitatively identical (or exactly similar) pink
elephants that merely exist in the mind, from truly qunatitatively (or
numerically) identical pink elephants that exist in the mind? Unless
entities are extended in the world—unless they exist in reality—there
seems to be no other sense in which ‘they’ can be, or exist.
This objection would be
another way to reject the truth of premise 2, since this premise
presupposes that the distinction between existence in the mind and
existence in reality is a legitimate one, and this objection directly
questions this assumption.
"Greater Than'" Mean?
Anselm's ontological argument
relies on the claim that something that exists in reality as well as in
the mind is greater than something that exists in the mind alone
(premise 2). We might wonder in what way existence in reality makes
something that exists in the mind greater.
Certainly if one were to
consider particular things—such as an ice-cold pitcher of beer or the
perfect mate—we would much prefer that these things exist in reality
than merely existing in the understanding alone. We might even say that
the beer and mate that exist in the understanding are somehow
‘bettered’—and, moreover, that the world itself is ‘bettered’—if these
presumably good things come to exist in reality (as well as in the
understanding). However, particular other things—such as an overly
vinegary bottle of wine or the most imperfect, annoying mate—would be
things that that we would not think would be made greater if they
In so far as we think that
‘greater’ means something like ‘better’ or ‘more improved’, it doesn’t
seem that annoying and evil things would be made ‘better’ or ‘more
improved’ if they existed in reality as well as in the understanding.
On the contrary, these things, among countless others, would presumably
be worse if they existed. What’s more, the world itself would surely be
worse if these things existed in reality rather than just existing in
the mind alone. So ‘greater’ cannot mean something like ‘makes the
world a better place’ or makes the thing itself a ‘better’ thing, or
else Anselm’s premise 2 would clearly be false. Certain things that
exist merely in the understanding should stay that way; nothing ‘great’
or ‘good’ would come from them existing in reality. And so, in an
attempt to find a plausible interpretation of premise 2 above—to find
an interpretation of this premise that might at least have a shot at
being true—Anselm must have had something else in mind when he uses
that predicate ‘greater.’
So what else could Anselm have
meant by ‘greater’? Well, first, it is clear that there are a few
things he couldn’t have meant. He couldn’t have meant ‘bigger’ or
‘heavier’ or ‘more powerful’. For even though we typically, in ordinary
usage, use the predicate ‘greater’ to mean these things, it is not
clear that we could even make sense of these predicates when applied to
the things that ‘exist in reality and in the understanding’ or to those
things that ‘exist in the understanding alone’.
For example, is a five-pound
turkey that exists in reality as well as the understanding ‘bigger’ or
‘heavier’ or ‘more powerful’ than a five-pound turkey that exists in
the understanding alone?
On one way of reading the
question, the answer seems vacuously true, since turkeys that exist
merely in the understanding don’t seem to be any particular size, weigh
any particular amount of weight, or have any sort of power. Indeed,
since things that exist in the understanding don’t exist in reality,
it’s hard to see how they have any properties whatsoever; for things
that don’t exist (in reality) can’t have any properties at all. But
then, if this is what Anselm meant by ‘greater’ then it doesn’t seem to
be of much help. For this would just amount to saying: things that
exist merely in the understanding don’t have any properties, so of
course things that exist in reality are ‘bigger’ and ‘heavier’ and
‘more powerful’ than things that exist merely in the understanding.
Unfortunately, this sort of ‘greatness’ is way too easily had. For not
only are things that exist in reality ‘heavier,’ ‘bigger’, and ‘more
powerful’ than things that exist merely in the understanding; they are
also ‘lighter’, ‘smaller’ ‘and ‘disappointingly less powerful’ than
things that exist merely in the understanding. Comparative properties
come cheap when one of the compared objects fails to have any
However, if you thought that
things that exist in the understanding might have properties—if you
thought that turkeys in the understanding have as much size and weight
and power that is attributed to them, then you will have to say that
the turkey that exists merely in the understanding is the same size,
has the same weight, and has just as much power as it would if it
existed in reality as well. To see this, ask yourself which weighs
more?: a five-pound turkey in the understanding, or a five-pound turkey
in reality? If, in light of the objection given in the previous
paragraph, you are going to claim that objects that merely exist in the
understanding have all of the properties that are attributed to them,
then you will have to maintain that both the five pound turkey that
exists in the understanding and the five pound turkey that exists both
in the understanding and in reality each weigh the same. In which case,
however, existence in reality doesn’t make something ‘greater’, if by
‘greater’ we mean ‘heavier.’ And similarly for ‘bigger’ and ‘more
So either the things that
exist merely in the understanding have the properties associated with
them or not. If they do, then it is not clear how a thing that exists
in the understanding can be ‘greater’ if it exists in reality, if by
‘greater’ we mean ‘bigger’ or ‘heavier’ or ‘more powerful.’ For a thing
that exists merely in the understanding will have just as much size,
weight, and power whether it comes to exists in reality or not, since
size, weight, and power are simply attributes that (we have assumed)
will be true of a thing whether or not a thing that exists in the
understanding exists in reality as well. However, if the things that
exist in the understanding do not have the properties associated with
them, then the claim that existence in reality is greater existence in
the understanding alone is vacuously true. And it would be just as true
to say, then, that existence in reality (as well as in the
understanding) is ‘less great’ than existence in the understanding
alone. So there must be something else that Anselm meant be premise
Perhaps he meant something
like ‘more causally efficacious’? Or perhaps he meant by ‘greater than’
something like ‘more vivid’, ‘louder’ or ‘more amplified’? We will
discuss these options in class.
Some Questions to Think About
What do you think that Anselm
can say in response to some of the objections above? In class I
suggested some of the moves he might make. Do find any of them
plausible? Which ones and why? Do you think that the argument
ultimately works? Or do you think that one of the above objections (or
any others you might have thought of) are ultimately devastating to the
argument? If the latter, which objection do you think is the most
damaging? Can you think of any other ways to run this argument than in
the way that Anselm did? If so, is this alternative better or worse and
if so, how?
Discussion of these questions
and more in class.
and Suggested Further Reading
Saint Anselm, Proslogium.
Arguments, SEP entry.
William L. Rowe, "The
Ontological Argument" in Reason and Responsibility, ed. Landau &
Gideon Rosen, Anselm's
Updated: Jan 07, 2011