The Argument
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Premise 1: God is a being than which nothing
greater can be conceived.
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Premise 2: Something that really exists is
bound to be greater than something that just
exists in thought.
The argument continued….
Premise 3: If there really is no being greater than God ,
God cannot only exist as a concept (in the mind).
Conclusion: Therefore God exists both in the mind and
in reality.
God
+
God
Key Quote
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‘ Why then, did the fool say in his heart ‘God
is not’ , since it is so obvious to the rational
mind that you exist supremely above all
things’.
Anselm.
Gaunilo’s Island
Gaunilo of Marmoutier is opposed to Anselm and
gave an immediate response to his Proslogion with an
argument he called ‘On Behalf of the Fool’. He
stated;
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“Oh God, or a being greater than all others, I could
not conceive at all, except merely according to the
word. An object can hardly or never be conceived according to
the word alone . . .”
It is impossible for humans to think of a fully perfect being!
Gaunilo’s Island
Gaunilo’s Island
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Gaunilo explains that if a friend told him about the most
perfect island, better than anywhere else in the world, he
could image it.
If his friend said that the island would be even better if it was
real rather than just in his imagination, then of course,
according to Anselm ontology, the island must exist.
But is this true? Gaunilo states that just because a person can
conceive of something, it doesn’t make it exist.
Gaunilo argues that if Anselm’s argument can be used to
prove the existence of a non-existent island, then it is flawed!
Anselm responds to Gaunilo
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You cannot possibly compare God
with and Island!
We know that islands have a
beginning and a likely end because
they are contingent – it can exist but
need not exist.
An island does not have an eternal
existence unlike God who is unique,
eternal and necessary.
Anselm’s second argument
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Continues with an a priori argument developed from
definition of God as ‘a being than which nothing greater can
be conceived’.
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What is greater?
1. A God who can be thought of as not existing.
or
2. A God who cannot be thought of as not existing.
Second argument continued . . .
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“Therefore, if that than which nothing greater can be
conceived exists in the understanding alone, the very being
than which nothing greater can be conceived is one than
which a greater can be conceived. But obviously this is
impossible. Hence there is no doubt that there exists a being
than which nothing greater can be conceived, and it exists
both in the understanding and in the reality.”
Anslem (Proslogion)
Second argument formally stated
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Premise 1: God is the greatest possible being so nothing
greater can be conceived.
Premise 2: It is greater to be a necessary being than a
contingent being.
Premise 3: If God exists only as a contingent being, so can
therefore be imagined not to exist, then a greater being could
be imagined that cannot be conceived not to exist.
Premise 4: This being would then be greater than God.
Premise 5: God is therefore a necessary being.
Conclusion: God must exist in reality.