1.1 Predicate 1: God is "That which
nothing greater can be conceived"
1.1.1 Predicate 2: It is better to exist in reality
and in the mind than it is to
exist in the mind alone
188.8.131.52 For example it is better to have a slice of cake in
your hand which you can eat than it is to merely
have a slice of cake in your imagination
184.108.40.206 Conclusion: Therefore God exists
1.2 "The fool says in
his heart that
there is no God"
2 Kant-Existence Is not a predicate
2.1 This is because existing doesn't add
anything to the essence of the being, it
only indicates that it occurs in reality.
2.2 He argues that the ontological argument works only if existence is a
predicate; if this is not so, then it is conceivable for a completely
perfect being to not exist, thus defeating the ontological argument
3 Responses to Kant
3.1 Kant’s criticism of the ontological argument is widely accepted, but
there have been a few dissenting voices. Some have insisted that
asserting that an object exists can change the way that we conceive of it.
If, having read about Socrates in the works of Plato, I discover that he is
a real historical figure, i.e. that he exists, then this extra information will
change the way that I think about him.
3.2 It can be suggested, to say that God is not a mere figment of
believers’ imaginations, but actually exists, is to add something
to the concept of God. Perhaps, then, Anselm’s comparison
between a God that exists and a God that does not is possible,
and the ontological argument survives Kant’s criticism.
3.3 Hartshorne argued that existence does add to the essence of the being, for
example an illness. A description of an illness is different to actually having it.
4 Gaunilo-The perfect island
4.1 Gaunilo argued, it is possible to construct an argument with exactly
the same form as the ontological argument, that purports to prove the
existence of the perfect island: the perfect island must exist, for if it did
not then it would be possible to conceive of an island greater than that
island than which no greater can be conceived, which is absurd.
4.2 Unless the theist can point to some relevant difference
between his argument for the existence of God and
Gaunilo’s argument for the existence of the perfect
island, then, then he will have to abandon the
ontological argument for the existence of God.
5 Responses to Gaunilo
5.1 A perfect island, presumably, is one with an abundance of lush
palm trees and pristine beaches. The more of these an island has,
the better it is. There is, however, no intrinsic maximum number
of trees or beaches that an island could have; for any island that
can be imagined, there is another, greater island, with one more
palm tree and one more beach. There is, then, no island than
which no greater island can be conceived. The concept of the
perfect island is incoherent; there can be no such thing.
5.1.1 On the other hand power, knowledge, and the other qualities of God all have upper limits which
when reached cannot be passed. There is, then, a difference between Gaunilo’s argument for the
existence of the perfect island and Anselm’s argument for the existence of God that advocates of the
ontological argument can cite as a reason for rejecting the former without committing themselves to
also rejecting the latter.
6 Descartes and the Triangle
6.1 Descartes argued that God's existence can be deduced from his nature, just as
geometric ideas can be deduced from the nature of shapes—he used the deduction
of the sizes of angles in a triangle as an example. He suggested that the concept
of God is that of a supremely perfect being, holding all perfections. He seems to
have assumed that existence is a predicate of a perfection. Thus, if the notion of
God did not include existence, it would not be supremely perfect, as it would be
lacking a perfection. Consequently, the notion of a supremely perfect God who
does not exist, Descartes argues, is unintelligible. Therefore, according to his nature,
God must exist
6.1.1 Simply put Descartes felt that removing existence
from God is the same as removing a side from a
triangle. You are changing its definition and thus it
can no longer be called a triangle, or God
6.1.2 Gassendi especially rejected Descartes' use of universal doubt, and his appeal to knowledge
gained through reason alone. Systematic doubt was acceptable, but to doubt everything was
unreasonable - indeed, not clearly possible. As a special case of that, perhaps, he held the
Aristotelians and Descartes alike guilty of rejecting the help of as wide a range of writers as
possible: Epicurus of course, but also Plato, Democritus, and other ancient writers.
7 Anselm's second argument
7.1 By definition, God is a being than which none greater can be imagined. A being that necessarily
exists in reality is greater than a being that does not necessarily exist. Thus, by definition, if God
exists as an idea in the mind but does not necessarily exist in reality, then we can imagine something
that is greater than God. But we cannot imagine something that is greater than God. Thus, if God
exists in the mind as an idea, then God necessarily exists in reality. God exists in the mind as an idea.
Therefore, God necessarily exists in reality
8 Aquinas' criticism
8.1 Aquinas suggested that people cannot know the
nature of God and, therefore, cannot conceive of God
in the way Anselm proposed. The ontological argument
would be meaningful only to someone who
understands the essence of God completely. Aquinas
reasoned that, as only God can completely know His
essence, only He could use the argument.
9 David Hume
9.1 As we have no abstract idea of existence (apart from as part of our ideas of other objects), we
cannot claim that the idea of God implies his existence. He suggested that any conception of God we
may have, we can conceive either of existing or of not existing. He believed that existence is not a
quality (or perfection), so a completely perfect being need not exist. Thus, he claimed that it is not a
contradiction to deny God's existence.
10 Alvin Plantinga
10.1 He argued that a being of maximal greatness and excellence exists in a possible world. If
this being exists in a possible world it must exists in every world or it would lack greatness
and excellence. Therefore a maximally great being exists in every possible world.
10.1.1 A being's excellence in a particular world depends only on its properties in that world; a being's
greatness depends on its properties in all worlds. Therefore, the greatest possible being must have
maximal excellence in every possible world.
11 Norman Malcolm
11.1 He argued that God's existence must either be necessary or
impossible. God's existence is possible because the concept of God is
not self contradictory thus the existence of God is necessary.