Very detailed mindmap addressing the strengths and weaknesses of the Ontological Argument. Green is for the argument and Red is against it. Philosophers include: Anselm, Gaunilo, Kant, Descartes, Norman Malcolm and Alvin Plantinga. Ideas include: Gaunilo's Island, Descartes' Triangle, Kant's Coin Analogy etc.
1.1 Gaunilo: a monk,
believer in God. Saw
flaws in the argument.
It's impossible to think of
a fully perfect being.
Our sense experience
shows there's always
potential to improve. He
could imagine the most
perfect lost island better
than anywhere else in
the world. Using
Anselm's argument, to
truly be perfect that
island must exist. But it
something doesn't make
1.1.1 Anselm's response: God can't be compared with an island. An island has a beginning and will
probably come to an end - it's contingent. It can exist, but it need not. Islands come into
existence through many means. It doesn't have eternal existence. God is unique and eternal
and necessary - it's logically impossible for him to not exist. Example - 'a widow is a woman
whose husband has died' = a necessary truth. If 'died' was changed to 'separated' then the
sentence wouldn't be true!
18.104.22.168 Islands have no intrinsic maximum,
you can always think of a better one.
God is the maximum in himself.
1.2 Gaunilo: You can't define something you
haven't experienced empirically. God's definition
is synthetic- it needs to be vertified.
1.3 Existence can mean
different things e.g
numbers exist without a
2.1 Descartes: Developed his own ontological argument. God is
a supremely perfect being. A being that is the most perfect
would necessarily contain all the attributes of perfection e.g
beauty, goodness, existence and eternal life. So God must
exist. He used analytic sentences to illustrate his argument.
If you speak of a triangle, then you are speaking of a shape
with 3 sides and 3 angles (that add up to 180 degrees). Just
as a triangle and its attributes are inseparable, God and his
attributes are inseparable.
2.1.1 Kant: If a triangle didn't exist in the first place it wouldn't have 3 sides and angles anyway. Defining a thing in an analytic way doesn't make it real
e.g. a unicorn had 1 horn- this is true but they still don't exist. He said existene isn't a predicate. There are some sentences where the subject can't
be thought of without the predicate e.g 2+2=4. But God and existence aren't like that as it's possible to think of a being who doesn't exist.
22.214.171.124 Coin example: Existing in reality may not add anything to an idea in the imagination.
The description of an object doesn't change by saying it's real not imaginary e.g an
imaginary pile of 100 coins and a real pile of 100 coins- it's the same amount of
126.96.36.199 The cat: saying 'the cat is black' adds to the cat's description. 'the cat exists' tells us nothing more
about the cat. If a property IS added as Anselm and Descartes suggest then 'the cat doesn't exist'
takes a property away. But this doesn't happen, in reality it's the cat that's take away, not the
2.2 Norman Malcolm: If God doesn't exist, he can't come into existence, as that would
require another force, meaning God was limited- which goes against God's definition.
So, if God exists he can't come into existence. This means that God's existence is either
impossible or necessary. but as the idea of God isn't logically absurd, God must
2.3 Alvin Plantinga: In a possible
world, a maximally great being
could exist. To be maximally
great, he must exist in all possible
worlds. So, the being must exist.