"Faith must be the starting point in the search of truth"................. This involves reasons in order to fully understand faith, leading to the truth about God. An ONTOLOGICAL ARGUMENT attempts to prove the that GOD EXISTS by establishing the necessity of God's existence through discussing the concept of EXISTENCE OR NECESSARY BEING
St. Anselm's Proslogion gave people a rational understanding about the belief in God...
“For I do not seek to understand in order that I maybelieve, but I believe in order that I may understand. ForI also believe this, that unless I believe, I shall notunderstand.”
God is ‘that than which nothing greater can beconceived’.Therefore God must have the attribute ofnecessary existence – otherwise God would not be‘that than which nothing greater can be conceived’.Therefore God must exist.
However it was objected by Gaunilo
I cannot form a notion of him from the realities, besides you said that there’s no reality like him
I don’t even have an idea of a being than which a greater cannot be conceived. I mean, as I hear the words, I cannot conceive of this being any more than I can conceive of God.
We conceive God by forming a notion of God beginning with the knowledge of less perfect things and raising our mind to the notion of a most perfect being.
We neither know such a being in itself, nor can we form an idea of it from anything like it. Obviously this is not true. For everything that is less good,insofar as it is good, is like the greater good. It is therefore evident to any rational mind that by ascending from the lesser good to the greater we can forma considerable notion of a being than which a greater in inconceivable
Even if we could conceive of a being than which none greater can be thought, it does not follow that this being exists in reality, but only in thought. We can think of any number of unreal things, and even impossible ones, which certainly have no existence outside the mind. For example, we can form the notion of an earthly paradise, the Isles of the Blessed, but that does not warrant our concluding that the islands really exist.