The Ontological Proof (I) For around a thousand years, various proofs for the existence of God have gone by the name ‘The Ontological Proof.’ The first person to give such a proof was St. Anselm of Canterbury in the 11th Century in his Proslogion. A Priori Proof: A proof the key premises of which can be known independent of any experience of the actual world.

Anselm also provided a very influential, short-hand definition for God. God = The Being than Whom none greater can be conceived. Actually, Anselm gave two Ontological Proofs. We shall concentrate on a simplified version of the second one. This Proof, in recent years, has been developed by such philosophers as Charles Hartshorne, Norman Malcolm, and Alvin Plantinga.

Anselm’s Second Ontological Proof (Simplified) If it is possible for God to exist, then God actually exists. It is possible for God to exist. Therefore, God actually exists. Now, at first glance, it would appear that no one could take this proof seriously. God’s mere possibility implies His actuality?

Many things are possible. For example, Polka Dot Zebras Striped Leopards Janet Jackson – The opera singer The mere fact that these things are possible does not mean they actually exist. Why should we believe that, in the case of God, and God alone, His possibility implies His actuality?

St. Anselm of Canterbury, Proslogion “It is possible to conceive of a Being which cannot be conceived not to exist, and this [Being] is greater than one which can be conceived not to exist. Hence, if [the Being] than which nothing greater can be conceived can be conceived not to exist, [it] is not [the Being] than which nothing greater can be conceived. But, this is an irreconcilable contradiction. There is, then, so truly a Being than which nothing greater can be conceived . . . , that it cannot even be conceived not to exist, and this Being Thou art, O Lord, our God.” St. Anselm of Canterbury, Proslogion

Now, this is very dense English translated from even denser Latin Now, this is very dense English translated from even denser Latin. What does Anselm mean here? We will restate the proof Anselm gives here as Lemma Θ. A lemma is a smaller proof done within the context of a larger proof. Here Lemma Θ is the proof for Step (A.) of the simplified version of Anselm’s Second Ontological Proof.

Preliminaries God – The Being than Whom none greater can be conceived, i.e. the Being Who is as perfect as any being can be, the maximally perfect Being. Some of God’s properties are omnipotence, omniscience, and omnibenevolence. Possible Reality – A reality that can be. A possible reality might or might not be actual. The possible reality in which George W. Bush is the President of the USA is actual. The possible reality in which Janet Jackson is an opera singer is not actual.

Lemma Θ is an example of the proof type known as Reductio ad Absurdum. In a Reductio proof, one proves the conclusion is true by proving its opposite is false. One proves the opposite of the conclusion is false by validly deducing from the opposite a self-contradiction. For example, ‘Today is and is not Thursday.’

Any statement from which one can validly deduce a self-contradiction, i.e any statement that reduces to an absurdity, must be false. Therefore its opposite, in this case, the conclusion one wants to prove, must be true. Lemma Θ Conclusion to Prove: If a Being, call the Being D, is God in one possible reality, then D is God in every possible reality. (This statement is a more precise formulation of Step (A.) in the simplified version of Anselm’s Second Ontological Proof.)

Suppose not, i.e suppose that D is God in some possible realities but not in other possible realities. (Assumption for Reductio) It is greater to be God in every possible reality instead of being God only in some possible realities. (Premise) In every possible reality in which D is God, one can conceive of another being D* who is God in every possible reality. (from A)

In any possible reality in which D is God, one can conceive of another being D* who is greater than D. (from 2 & 3) In any possible reality in which D is God, one can conceive of another being D* greater than the Being than Whom none greater can be conceived. (from 4 and the Definition of God) [(5.) is a self-contradiction]

Thus, if a being, call the being D is God in one possible reality, then D is God in every possible reality. (from 1 thru 5 by Reductio ad Absurdum) Philosopher J. N. Findlay sums up the insight of Lemma Θ (and Anselm’s original proof): “It is [contrary to the demands and claims inherent in religious attitudes that their object] should possess its various excellences in some merely

“adventitious manner. It would be quite unsatisfactory, from the religious standpoint, if an object merely happened to be wise, good, powerful and so forth, even to a superlative degree.” J. N. Findlay, Mind, 57 (1948) In other words, a being who happens to be God in one possible reality, but who is, for example, Pee Wee Herman in every other possible reality is not a being worth worshipping in any possible reality.

To be worthy of worship, to be truly God, in ANY possible reality, a being must be maximally perfect in EVERY possible reality. But, for a being to be anything in every possible reality means the being must exist in every possible reality. Thus, if a being is God in even one possible reality, then the being is God in every possible reality. Since actual reality is a possible reality, if a being is God in even one possible reality (i.e if it’s possible for God to exist), then God actually exists.

Norman Malcolm, Knowledge and Certainty Today, thanks to the efforts of Hartshorne, Malcolm, and Plantinga, almost everyone concedes the truth of Step (A.) of the simplified version of Anselm’s Second Ontological Proof. Today, if someone challenges Anselm’s Second Ontological Proof, they tend to deny Step (B.) of the simplified version, i.e. that it’s possible for God to exist. “The only intelligible way of rejecting Anselm's . . . [proof] is to maintain that the the concept of God, as [the] Being greater than which cannot be conceived, is self-contradictory or nonsensical.” Norman Malcolm, Knowledge and Certainty