The Ontological Argument

The Ontological Argument

1. Anselm's Argument - Dreamboats and Turkeys

2. Anselm defines God as "That which nothing greater can be conceived"

3. i. The concept of God is understood. Whatever is understood exists in the understanding. So, God exists in the understanding.

   • ii. Suppose God only exits in the understanding, and not in reality. Then a greater being than God can be conceived - one that exists in reality. BUT God is defined as that than which nothing greater can be conceived. So, no greater being can be conceived, by definition.But now we have a contradiction - so our original supposition was false (that God only exists in the understanding).
     • Reductio Ad Absurdum Argument
       • You accept some hypothesis for the sake of argument, and then you show that the hypothesis leads to a contradiction, or some other conclusion you know independently to be false. Hence the hypothesis can't be true, so it has to be rejected.
     • This argument is a priori. It purports to prove God's existence simply by considering the definition of God.

4. Objections

   • A monk named Guanilo pointed out that if the argument were good, it could be used to prove all sorts of conclusions that were too good to be true. Eg, That there exists a perfect island than which nothing greater can be conceived; also: see"Dreamboat"
   • Existence is not a predicate.
   • "The problem lies in the ambiguity lurking in the comparison of 'reality' and 'conception'" (Blackburn) "Real turkeys are heavier than imagined turkeys" - Imagined turkeys cannot be compared against real turkeys. i.e. Even if God only exists in the understanding, it does not follow that a greater being can be described or imagined.
   • God does not exist in the understanding. It is true that we have an idea of God, but he does not actually exist in the understanding.