The Arguments for the Existence of God

Ontological

• Only ‘a priori’ argument – reason/logic alone.

• Also a Deductive argument: only one conclusion can be drawn if the premises (logical arguments) are correct.

• If an error occurs in a premise = wrong conclusion.

• teleo, cosmo, moral: are all Inductive – number of possible conclusions from premises (and all ‘a posteriori’ )

• E.g. The universe has a middle and end – Anything that has a middle and end must have a beginning– The beginning of the universe is God.

Anselm explains his argument for the existence of God in ‘The Proslogian.’

Proslogian Two:

Premise one: God is “that than which nothing greater can be conceived (imagined)”

Premise two: “It is better to exist in reality than only in the imagination.”

Premise three: “If God only exists in the imagination it would be possible to imagine a greater God that is real.”

Conclusion: Therefore God must exist in reality.

= Deductive argument

Gaunilo• Gaunilo’s book “on Behalf of the Fool”• Challenged Anselm’s logic• Just because imagine a perfect island does not

mean it exists in reality.• In fact we know it does not• You would be a fool to think so.

Anselm’s Reply• Gaunilo missed the point.• God isn’t a perfect thing, like an island• God is THE perfect thing.• Islands can always be improved, God cannot.

• Alvin Plantinga: Islands have no “intrinsic maximum.”

Anselm’s second version in Proslogian Chapter Three

• God has Necessary Existence, since it is greater to be a necessary being that a contingent one.

DescartesDescartes adds to Anselm’s argument=• God is perfect• Part of the quality (predicate) of perfection is

‘existence’ just the same as ‘omnipotence, omniscience’ are also predicates of God’s perfection.

• God cannot lack existence otherwise God would not be perfect.

• A predicate adds qualities to the subject.• Therefore existence adds qualities to the perfection

of God.

Descartes and the Triangle• A triangle needs three sides• God requires that He exists.

• Trying to imagine God without the predicate of existence is illogical, like trying to imagine a triangle without three sides.

• These ‘facts’ do not require empirical proofs in order for them to be truths (that's why it is an ‘a priori’ argument)

• This makes them analytic statements (meaning is within the statement)

Kant1. If you have a triangle, you have to accept it has

three sides.

2. However if you do not have a triangle, you don't have three sides.

• 3 sides of a triangle is an analytical statement. • But this says NOTHING about the existence of a

triangle.• Existence is not a predicate/ quality of a triangle.

• Norman Malcolm modern supporter of the Ontological

• Kant’s criticism failed in one important respect.

• You either have a triangle or not

• But, by Anselm’s definition:

That God is that than which…. And that God is not just anything like a triangle or Island but THE perfect Necessary Being

• You simply cannot have no God.

• Therefore the situations are not exactly parallel.

Supporters of Anselm and Descartes:

Plantinga (also a modern supporter):

1. It is possible to imagine our world with a being who has “maximal greatness.”

2. A being has “maximal greatness” if it exists in every possible world

3. Therefore such a being must exist in our world.

But Davies adds: such a being is “possible” but not actual.

Supporters:

Russell concludes

• Existence is not a predicate –if it was then:

E.g.

Men exist

Santa Claus is a man

Therefore Santa Claus exists