Chapter 6:

1. Chapter 6: Ontological arguments for God’s existence:

2. Ontological argument • Derived from the Greek terms ontos (being) and logos(reason or rational account) • First developed by Saint Anselm of Canterbury, the argument takes a variety of forms • The common theme among them is that they begin a priori – proceeding from the mere concept of God – and conclude that God must exist

3. Anselm’s ontological argument Everyone is able to understand by the term “God” a being than which none greater can be conceived So, a being than which none greater can be conceived exists in the mind (the understanding) when one hears about such a being We can conceive of a being than which none greater can be conceived which exists both in the mind and in reality

4. Anselm’s argument continued • To exist in reality is better than to exist in the mind alone • If, therefore, a being than which none greater can be conceived exists in the mind alone and not in reality, it is not a being than which none greater can be conceived • Therefore, a being than which none greater can be conceived exists in reality.

5. Guanilo’s objection Everyone is able to understand by the term “Perfect Island” the greatest possible island(GPI). So, a GPI exists in the mind We can conceive of a GPI that exists in the mind and reality Existence in reality is greater than existence in the mind alone If a GPI exists in the mind alone, then it is not the GPI Thus, a GPI exists in reality But since a GPI does not exist in reality, the argument structure (which Anselm also utilizes) must be flawed

6. Kant’s objection • Existence is not a predicate such that it is a property which can be affirmed of a thing • Existence does not add to the concept of a thing; rather, existence is the instantiation of a thing • The example of a black, existing cat

7. Plantinga’s modal argument It is possible that a being exists which is maximally great (a being we can call God) So, there is a possible world in which a maximally great being exists A maximally great being is necessarily maximally excellent in every possible world(by definition) Since a maximally great being is necessarily maximally excellent in every possible world, that being is necessarily maximally excellent in the actual world Therefore, a maximally great being exists in the actual world

8. Objections • God’s existence is a logical or metaphysical impossibility • Possible worlds and the semantics they employ are problematic • Fairies, ghosts, gremlins and unicorns can be made “plausible” through the same argumentation (similar to “Perfect Island”)

9. Martin’s special fairy argument It is possible that a special fairy exists So, there is a possible world in which a special fairy exists A special fairy is necessarily a tiny woodland creature with magical powers in every possible world Since a special fairy is necessarily a tiny woodland creature with magical powers in every possible world, that fairy is necessarily a tiny woodland creature with magical powers in the actual world Therefore, a special fairy exists in the actual world

10. Questions for discussion • Is it greater to exist than to not exist, as Anselm claimed? How does your answer affect Anselm’s argument? • Can you conceive of God’s non-existence? If so, what follows from this regarding the ontological argument? • How does the ontological argument differ from other classic arguments for the existence of God?