• If we define a perfect being as one that possesses every perfection essentially, and if we suppose that necessary existence is a perfection, then the existence of a perfect being follows from a single premise: that a perfect being (so defined) is possible. (That is, is not intrinsically impossible, i.e.—“a square circle”)
• If a perfect being is possible, then a perfect being exists in some possible world.
• If a perfect being exists in some possible world, then in that world it is not only existent but necessarily existent—necessary existence being a perfection.
• Necessary existence, however, is the same thing as existence in all possible worlds: a necessarily existent being is just a being whose non-existence is impossible, and the impossible is just that which is not included in any of the possible ways for reality to be (which is not included in any possible world).
• A being that exists in some possible world w, however, must exist in this world, our world, the actual world—for if that being did not exist in the actual world, it would not be necessarily existent in w; that is, it would not be true in w that it existed in every possible world.
• This being, moreover, must not only exist in this, the actual, world, but it must have all perfections in this world—for if it lacked some perfection in this world, it would not have that perfection essentially in w.
• If, therefore, there is a possible world w in which there is a necessarily existent being that has all perfections essentially—that is to say, if a perfect being is possible—there must actually be a being that has all perfections.
• In sum, given only that it is not intrinsically impossible for a perfect being to exist, a perfect being actually does exist.
• But what about the antecedent of this conditional? Is it true? Is it so much as possible for a perfect being to exist? Difficult.
• Consider the concept of a “correct atheist,” the concept, that is, of someone who believes, and rightly, that there is no perfect being. If the concept “correct atheist” is a possible concept, the concept “perfect being” is an impossible concept. (For if “correct atheist” is a possible concept, then in some possible world there is no perfect being; and, as we have seen, if “perfect being” is a possible concept, then in no possible world is there no perfect being.) And if “perfect being” is an impossible concept, “correct atheist” is obviously a possible concept.
• One of these two concepts is therefore possible and the other impossible.
• But which? There seems to be no way to conclusively answer the question.
• Although there seems to be a version of the ontological argument that is without logical flaw, the argument proceeds from a premise such that there is no way to decide whether it is true.
• Or no way other than this way: someone may somehow know that there is a perfect being; that person will, of course, know that a perfect being is possible.
• It would seem, therefore, to be impossible to know that the premise of the ontological argument is true without first knowing that its conclusion is true.
• The ontological argument, therefore, cannot serve as a means by which someone can pass from not knowing whether a perfect being exists to knowing that a perfect being exists.
This is what Anselm said up front, knowing that he depended on knowing God already in order to come to this new understanding of his faith. He was dependent upon such other avenues of knowledge as history, revelation, personal experience of God, and the like.
And, of course, isn't that the point? All one has to do is read the passionate language of Anselm regarding God's love for us in order to realize that God has no interest in being "necessarily existent" in our lives, but rather that God wants us to enter into the fundamental reality of our existence: the Love that Is God. It seems to me that the biggest part of the work in getting this text across to students is to break them out of the easy mistake most people make: reducing God to a god. God is not a god. Infinite is not finite, not even "really big" finite. God has no environment, no cause, no context. Most of the flaws in understanding related to these points, in the way people tend to think on this matter, is to think of God as being on some kind of scale with us, even if superlatively "bigger." To wrap your mind around God as the Ultimate Reality, "behind" which there is no other context, is a major shift in thinking. And a necessary one if understanding is to occur. Which is why Anselm originally entitled the work Faith Seeking Understanding.