What is the ontological argument for the existence of God?

Those who attempt to defend the claims of the Bible generally use a couple major types of arguments. One group is called presuppositionalism, or presuppositional apologetics.  arguments. The person presupposes the claims of the Bible to be true and then offers evidences to support that starting principle. The other group is called classical apologetics. The person attempts to show evidences for the claims of the Bible or the existence of God by using independent arguments for the existence of God and the reliability of the Bible.

Classical arguments for the existence of God include the teleological, cosmological, moral and ontological arguments. The ontological argument is different from the others because it offers evidence for God based only upon the philosophical reasonings of man. No proofs outside the thoughts of man are offered. Because of this the ontological argument can be challenging to understand. It is a logical and philosophical argument likely to be appreciated by someone who has studied those systems. The ontological argument can be briefly stated.  Nothing can be imagined that is greater than God, therefore God must exist.

The ontological argument is not an empirical argument. It does not offer claims that can be examined using the scientific method. It does not make claims that can be supported by external evidence. The ontological argument seeks to show the existence of God based upon the definition of God. It is believed that Anselm, the Archbishop of Canterbury during the 11th century, first formulated this argument. The argument has been made in a couple different ways, but the strongest seems to be this:

  • God, by definition, is a being greater than any other which can be imagined (No one can imagine a being greater than God)
  • A being which exists in thought and in reality is greater than a being which exists only in the imagination
  • If God exists only in thought, then men can devise a being which is greater than God
  • No one can devise a being greater than God (we cannot imagine a being greater than the greatest being imaginable)
  • Because men have a conception of God and can imagine none greater, God must exist.

To state the argument another way; the God of the Bible is conceived as having all perfections. He is infinite in being, eternal in existence and limitless in knowledge, might and presence. None can imagine a being that is greater than God. If God is that which is greater than any imagination of man, God must exist.

This argument is limited by a proper definition of God- a person can easily imagine a being greater than the god Thor, but one cannot imagine a being greater than the infinitely perfect God of the Bible, and it is limited by the philosophical complexity of the argument. Some have accused the ontological argument of being little more than an elaborate word game. The biggest problem with the ontological argument is its total reliance on human reasoning to attempt to deduce the existence of God. Because of the corruption of sin upon the mind of men none will turn to God by the power of logic. The Word of God makes that clear the things of God cannot be discerned by the unsaved man apart from the work of the Holy Spirit. (2 Corinthians 2:14) There is no being greater than God. We know of His existence and His greatness because He has made Himself known to man. In His grace God has given us His Word which tells us of His glory.