Ontological Argument
for God
Introduction to Philosophy
Jason M. Chang
Lecture Outline
1.
Background
2.
Major ideas
3.
The argument
4.
Objections
A.
B.
C.
Gaunilo’s objection
Perfect objection
Kant’s objection
Background
Background
St. Anselm 1033-1109 AD
o
Definition of “ontology”
o
A priori vs. a posteriori
o
St. Anselm of Canterbury
Major ideas
Major ideas in the ontological argument
•
Necessary vs. contingent attributes
o
•
Definition
Attributes of a Perfect Being (the greatest possible being)
Major ideas
Major ideas in the ontological argument
•
Existence in reality vs. existence only in the understanding
•
Anselm on existence
o
The claim
o
Reasoning
The argument
(P1) God is the greatest possible being.
(P2) Existence in reality is greater than existing only in the
understanding.
Therefore,
(C) God must exist (given that He is the greatest possible being)
Note: This is a simplified version of Anselm’s argument. In the original version, Anselm shows that believing
that the greatest possible being exists only in the understanding leads to a contradiction. (reductio)
Common objections
Gaunilo’s objection
Gaunilo’s objection
•
Strategy
o
•
Gaunilo of Marmoutiers
Refute (P2)
Perfect island
Gaunilo’s objection
“Suppose that a person tried to prove to me
by this reasoning that this island actually
exists […] [If I believed him], I would not
know which I ought to regard as the greater
fool: perhaps myself for supposing that I
should allow this proof, perhaps him for
supposing that he had established with any
certainty the existence of this island”
Perfect murder objection
Greatest demon objection
•
Strategy
o
•
Denies that “existence”
makes a thing greater
Q  Is something really greater if it
exists in the world than if it exists
only in the mind?
Perfect murder objection
Things in which “existence”
adds to their goodness
Things in which “existence”
detracts from their goodness
Kant’s objection
Kant’s objection
•
Strategy
o
Immanuel Kant (1724-1804)
Deny that “existence”
is an attribute
Kant’s objection
Attributes are characteristics or properties ascribed to something
-Intelligent
-Witty
-Thin
-Fit
Many of these
attributes can add
to the value of
something
Kant  EXISTENCE is not an attribute