The earlier of the two volumes on Natural Theology relies on the cosmological argument; the later - obviously an afterthought - tries to vindicate the ontological argument as an alternative basis for theism, but awkwardly and with manifest uneasiness.
Finally the Ontological argument sums up the truth in the two previous arguments, and gives it worthier utterance in its vision of the philosophical Absolute.
He regards the Ontological argument strictly so called as having been exploded by Kant.
The existence of God is maintained by Albert and Aquinas to be domonstrable by reason; but here again they reject the ontological argument of Anselm, and restrict themselves to the a posteriori proof, rising after the manner of Aristotle from that which is prior for us to that which is prior by nature or in itself.
The middle ages, in the person of Anselm of Canterbury, contribute the first clear form of the Ontological argument for theism.
On the other hand, as the first to formulate the ontological argument (in his Proslogion) for the existence of God, he joins hands with some of the profoundest names in modern philosophy.
He accepts the ontological argument with a.
It is no more than characteristic of Kant's whole speculative philosophy that he should' think the Ontological argument the one which comes nearest to st,-cess (yet the Ontological argument is held to prove - or rather to point out - not that God must exist, but that we think of him as necessary if we think of him as existing at all).