Now, with all this technical material in place,
we're in a position to go back to Anselm's
ontological argument, and try to reconstruct it
as an argument with premises and a conclusion.
And then we can ask, does it do the job we want?
Is it a valid, sound argument that's
potentially convincing to the reasonable agnostic?
Let's start with a reconstruction.
Let us now apply this apparatus to Anselm's argument,
his ontological argument of the existence of God.
OK.
The way we're going to reconstruct it here,
the first premise of Anselm's argument, call it P1,
is this: Either God exists in the understanding
but not in reality, or God exists in the understanding
and in reality.
After all, Anselm said, even the fool understands
what it is for there to be a god.
The issue is whether the God really exists.
Second premise of the argument: If God
exists in the understanding but not in reality,
then we can conceive of a thing greater than God,
a thing different in virtue of existing in the understanding
and in reality, but otherwise just like God.
How much more awesome, extraordinary, great
would God be if he existed in the understanding
and in reality than if he just existed in the understanding
Premise three: It is not the case
that we conceive of a thing greater than God.
Remember, this was just part of the idea of God.
This was not a controversial claim about the world.
And some said this was just part of the idea of what
it is to be God.
It's to be a thing such that you can't be any better.
Name a thing, call it God, and concede
that it could be better, and you're not really
talking about God.
Conclusion: God exists in the understanding and in reality.
OK.
So now, reconstructed this way, we have to look and see
is this argument good?
And we have these tests that we've
developed for goodness in an argument.
First test-- validity.
Is the argument valid?
Is it the case that it's possible
that the premises be true and the conclusion false?
If that's true, then it's invalid.
If it's impossible for the premises be true
and the conclusion false, then it's valid.
OK, looking at an argument like this,
it's actually rather hard to tell immediately
whether it's valid.
After all, it's got lots of words in it.
The words have got some clauses.
There are lots of "and"s, lots of "but"s.
It appears quite logically complicated.
So to see whether an argument like this is valid,
it's helpful to reduce it, to simplify it,
to look at its form.
And we'll do this by replacing some
of the clauses in the arguments with schematic letters.
You'll see what I mean as we go on.
So first, take this phrase.
"God exists in the understanding but not in reality."
Let's just put the letter X in place of that phrase.
The argument now looks like this.
Now take the phrase, "God exists in the understanding
and in reality."
That occurs twice in the argument.
Let's put the letter Y in place of that phrase.
The argument now looks like this.
Finally, let's take the phrase, "we
can conceive of a thing greater than God."
That, too, occurs twice in the argument.
We can replace it with the letter Z.
And the argument looks like this.
Still a bit jumbled-- compress it.
And we have an argument like this.
Premise one-- either X or Y. Premise two--
if X, then Z. Premise three-- it's
not the case that Z. Conclusion-- Y.
Is that a valid argument?
Is it possible that the premises be true
and the conclusion false?
It is a valid argument.
It is impossible that the premises be true
and the conclusion false.
Any argument with this form is valid.
Why is that?
Well, you can kind of see just by looking at premise three.
Premise three says, "it's not the case that Z".
Now look at premise two.
Premise two says, "if X, then Z."
Because it's not the case that Z and if X, then Z,
it must be not the case that X.
Now look at premise one.
Premise one says, "either X or Y."
If either X or Y, and it's not the case
that X, then it must be that Y. That's
what the conclusion says: Y. So it's
impossible the premises be true and the conclusion false.
So, well done, Anselm.
His argument passes our first test.
What about the remaining two, soundness
and, most importantly, potential convincing-ness
to the reasonable agnostic?
Well, here is where things get a bit hairy for Anselm.
To really evaluate whether or not the argument is sound
and convincing to the reasonable agnostic,
we need to look at these premises
and understand what on earth they mean.
There are some very strange phrases in here, most notably,
God exists in the understanding but not in reality.
What is it to exist in the understanding
but not in reality?
Existing in the understanding-- that's a very strange phrase,
not one that we ordinarily use in everyday life.
So there are different ways to interpret this.
Here's one way of understanding what this means.
So to say God exists in the understanding but not reality
is to say, we can conceive of or imagine God existing,
but he doesn't exist.
Interpreted that way, the argument comes out like this.
I'll read it.
Premise one-- either we can conceive of God existing,
but he doesn't exist.
Or we can conceive of God existing, and he does exist.
Premise two-- if we can conceive of God existing
but he doesn't exist, then we can conceive
of a thing greater than him-- a thing just like him,
but existing
Premise three-- it's not the case
that we can conceive of a thing greater than God.
Conclusion-- we can conceive of God existing, and he does
exist.
OK.
Put like that, how good is the argument?
Well, look a premise one.
That looks pretty good.
Either we can conceive of God existing, but he doesn't exist.
Or we can conceive of God existing, and he does exist.
So long as we conceive of God existing,
premise one is going to be true.
The problem comes with premise two.
Premise two, on this interpretation,
looks kind of senseless, or if senseful false.
If we can conceive of God existing, but he doesn't exist,
then we can conceive of a thing greater
than him, a thing just like him, but existing.
That just makes no sense.
If we can conceive of him existing, but he doesn't exist,
then we can't do something further,
namely conceive of him existing.
When you conceive of him existing,
there's nothing further you can do to conceive of him existing.
You're already doing that.
So premise two just comes out as manifestly false.
And so certainly the argument is unsound and certainly
not persuasive to the reasonable agnostic.
So is there another way of interpreting that key phrase,
"God exists in the understanding but not reality"?
Well, here's something probably closer
to what Saint Anselm had in mind.
What the phrase means is this.
There's a God.
And he has the property of existing in the understanding,
but he lacks the property of existing in reality.
Understood that second way, the argument comes out like this.
Either there's a God with the property
of existing in the understanding,
but lacking the property of existing in reality.
Or there's a God with both properties.
If there is a God with the property
of existing in the understanding,
but lacking the property of existing in reality,
then we can conceive of a thing greater
than him, a thing with the property of existing
in reality, but otherwise just like him.
Premise Three-- it's not the case
that we can conceive of a thing greater than God.
Conclusion-- there is a God with the property of existing
in the understanding and, crucially, the property
of existing in reality.
Fine.
But now look at that first premise.
Is that something that the reasonable agnostic, somebody
who is suspending judgment concerning
the existence of God, will accept?
Well, remember that the reasonable agnostic
supposes that God might not exist.
For the reasonable agnostic, that's
a live possibility, as well as the possibility
that God does exist.
Suppose the God doesn't exist.
Will the reasonable agnostic then
accept that there's a God with the property of existing
in the understanding?
He might think not.
The reasonable agnostic might say, "No.
In supposing that God doesn't exist,
I don't suppose there is a God with a funny property, existing
in the understanding.
In supposing that God doesn't exist,
I suppose there isn't a God."
So on this interpretation, the reasonable agnostic
is going to reject the first premise,
or at least not accept the first premise of the argument.
Let's go into that in little bit more detail.
Here's an example of something that the reasonable agnostic
might suppose.
He might suppose the God doesn't have a beginning or end.
What does that mean?
Well, maybe for the reasonable agnostic,
supposing that God doesn't have a beginning or end
does involve supposing that there's
a thing, God, with a particular feature,
not having a beginning or end.
The reasonable agnostics might further
suppose that, say, God doesn't like evil.
And that might involve supposing that there's
a thing, God, with a particular feature, not liking evil.
But when the reasonable agnostic supposes that God does not
exist, that does not involve supposing
that there's a thing, God, with that particular feature,
nonexistence.
Various philosophers over the course of history
have made this point-- David Hume,
in the 18th century; Immanuel Kant, also in the 18th century;
Russell, in the 20th century.
Existence is not a property.
When we say a thing exists-- and most pertinently--
when we say a thing doesn't exist--
we don't suppose that there is the thing,
and that it has this funny property, not existing.
As Russell put it, to say that would
be to think that there was some difference between existing
and being.
Where does this leave us with the ontological argument?
Well, it leaves us with an argument that works-- well,
the argument doesn't work-- but appears
to work in virtue of what philosophers
call an equivocation.
There's different ways of understanding this phrase,
God exists in the understanding but not in reality.
On one way of understanding the phrase,
the first premise of the argument
looks fine, and looks like the kind of thing
that a reasonable agnostic is going to accept.
But the second premise is bad.
On the other way of understanding the argument,
the second premise looks fine, the kind of thing
that a reasonable agnostic might accept,
but the first premise is bad.
So in so far as the argument might appear convincing,
it's because each premise, when assessed independently,
has a reading that appears plausible.
But when one reading is given to all the premises
as one way of interpreting the words and all the premises,
then the argument comes out either unsound or unconvincing.
So what do we say about Saint Anselm all those years ago?
Was he just lumbering around, making a basic error?
Confused?
Silly?
Well, that would be premature for a couple of reasons.
Firstly, this was just one interpretation
of the ontological argument that I've given.
Anselm's words support many different interpretations.
Maybe you can have a go at trying to reconstruct a better
argument in premise and conclusion form.
See if you can revive the ontological argument.
Plenty of philosophers since have thought that they could.
And the second reason to think that he was not
just blundering around, foolish, making an elementary error,
is that he was pointing to something
that philosophers and people who think
hard about the meanings of words today
still find interesting and kind of mysterious.
When I say a phrase like, "the Tooth Fairy does not exist"--
I say of something that it doesn't exist, what do I mean?
We'd better not mean this.
There's a thing, the Tooth Fairy, with a feature,
not existing.
But if I don't mean that, what do I mean?
What is it to say the Tooth Fairy
that the tooth fairy doesn't exist,
if not to say of a thing, the Tooth Fairy,
that it has a feature, not existing?
This is something that philosophers
of language, people think about the meanings of words,
still think about, and are slightly puzzled by,
and still have different theories about even today.
And so he was, at the very least,
pointing to an issue that is of continuing interest.
That's Anselm's ontological argument
for the existence of God.
Looks like it's mistaken.
Looks like it doesn't do the job we want done.
Perhaps you can do a better job of reconstructing it.
Based on Anselm's words, perhaps you
can make an effort to come up with a better
argument for the existence of God.
I encourage you to give it a shot.
Meanwhile, we're going to move on.
Next time, we're going to look at some more influential
to contemporary people arguments for the existence of God
having to do with design.
Basic idea-- the world around us shows
evidence of having been made.
And where there's making, there's a maker.