1. Etienne Gilson (1937) The Unity of Philosophical Experience (New York: Charles Scribner’s Sons), Chapter 12, esp. p. 316.
2. St. Anselm, Proslogion, Chapter 2–4 is the classical source, in Alvin Plantinga (ed) (1965) The Ontological Argument (Garden City, NY: Anchor Books), pp. 3–19.
3. Alvin Plantinga (2001) “A Contemporary Modal Version of the Ontolog-ical Argument,” in Michael Peterson, William Hasker, Bruce Reichenbach, and David Basinger (eds.) Philosophy of Religion: Selected Readings, 2nd edn (New York: Oxford University Press), pp. 181–93.
4. Cf. Richard Swinburne (2004) The Christian God (Oxford: Oxford University Press), Chapter 5, discusses possible interpretation of necessity as it relates to the Christian God.
5. The cogency of this distinction is disputed by W. V. O. Quine (1963) From a Logical Point of View, 2nd edn (New York: Harper & Row), esp. Chapter 8, who thinks that necessity cannot be predicated of things, only of propositions. This view seems to be widely embraced among philosophers.