Concerning the Ontological Argument

For the materials of my discussion, I fall back upon Descartes. This philosopher demonstrates the existence of God in his Third Meditation. The ontological argument, however, is given not in the Third but in the Fifth Meditation. It is there expressed in a curious manner. It would seem, to go by literary expression, that he at this point unexpectedly thought of the argument, stumbled upon it, as it were. "Of the essence of material things, et derechef, de Dieu, qu'il existe"--and again, of God, that He exists. The title is in itself provocative. We are told of the essence of material things. The consideration of quantity, of extension, leads to the recognition that size, shape, position and motion can be distinguished with respect to the body to which we attribute extension. Thus he is led to, or at any rate introduces, a doctrine of essence. There is an infinity of ideas that are forms, essences, or determinate natures, immutable and eternal. Most significantly of all, these determinate natures have not been invented by me, says Descartes, and do not in any way depend upon my mind. After one more paragraph there follows the ontological argument.