Criticisms of Anselm's
Ontological Argument
BETH EVANS…read more

Gaunilo's Criticism 1
Anselm's argument moves from the existence of an idea to the existence of
a being which cannot simply be done
You cannot define something into existence.
Gaunilo thought that the ontological argument would show existence to all
kinds of non-existent things.
Gaunilo uses Anselm's strategy of deduction in forming the existence of a
perfect island as a counterexample to the ontological argument
It is a conceptual truth that an object is an island than which none greater
can be imagined
If the ontological argument worked then the argument for the existence of
the perfect island also works as they both have the same logic.
As we have no reason to believe in the perfect island it must be rejected
similarly to the idea of God's existence
Anselm's counterargument was that God is different to everything else as
he is necessary whereas everything else is contingent.…read more

The Perfect Island
An object exists as an idea in the mind.
An object that exists as an idea in the mind and in
reality is greater than an object that exists only as an
idea in the mind.
Thus, if an object exists only as an idea in the mind,
then we can imagine an island that is greater than an
object (that is, a greatest possible island that does
exist).
But we cannot imagine an island that is greater than
an object.
Therefore, an object exists.…read more

Gaunilo's Criticism 2
Gaunilo also stated that there is a difference
between understanding and conceiving e.g.
you can understand the pain of childbirth however
you cannot conceive it until you actually experience
it.
With this idea Gaunilo said that you cannot define
God.
Also an atheist can understand the argument but
that doesn't mean that they accept it, it is only a good
argument for believers.…read more

Aquinas's Criticism
St. Thomas Aquinas rejected the idea that God's existence can
be deduced from the concept of God in reality.
As people have different ideas of God the ontological
argument only works to convince those who define God in the
same way.
Aquinas believed you have to work inductively, a posteriori
and synthetically in order to prove God's existence and that
God isn't self-evident like Anselm claims.
Also even if everyone has the same concept of God as the
greatest being this doesn't actually mean that he exists
physically only that he exists mentally.
God is unlike anything we have an idea of as he is beyond
human understanding.…read more