Ontological Argument

In the Philosophy of Religion, the Ontological argument is one of the four traditional arguments offered as a proof for God's existence. This argument takes its name from the Greek ontos - 'being' and attempts to prove God's existence is necessary (i.e., could not be otherwise). There are many versions of the Ontological argument (the most famous being that of St. Anselm of Canterbury 1033-1109) but they all work in basically the same way:

  1. It will be granted that we have the idea of 'God' (i.e., 3-O God or Theism).
  2. The idea 'God' entails existence (in much the same way that the idea of 'square' entails four-sidedness).
  3. Therefore, God must exist.

Of all the arguments for God's existence the Ontological argument is the most philosophically interesting, and it still receives a good deal of attention by contemporary philosophers interested in the problem of God's existence.