Halifax

I usually refrain from arguing philosophy and politics on internet forums, especially anything which touches on religion, but as a philosophy student, and a Christian, and a person tired of hearing the same old historical, psychological, and anthropological analyses of religious belief, I figure I should add my two cents, or rather my understanding of Alvin Plantinga's two cents. I find his reformulation of the ontological argument for God's existence rather compelling.

For those unfamiliar with it, the ontological argument traces back to St. Anselm of Canterbury, the 11th century Archbishop of Canterbury. Simply put, his argument claims that since I can conceive of God, and God, by definition, is a being than which nothing greater can be conceived, he must exist; for to exist in reality is greater and more perfect than to exist merely in the mind, and since I can conceive of a maximally great and perfectly perfect being, such a being must embody the quality—namely existence)—to fulfill and effect this conception. If there was not such optimal perfection, I would be unable to conceive of it. There must be a prototype for the type of thought in my mind.

In summary, (taken shamelessly from Wikipedia):
1. God is, by definition, a being than which nothing greater can be conceived (imagined).
2. Existence in reality is greater than existence in the mind.
3. God must exist in reality, if God did not then God would not be that which nothing greater can be conceived (imagined).

Now, I know that the original ontological argument has its flaws as evidenced by the numerous detractors it has acquired in the 900-something years since its introduction. For my own part, I do accept Kant's objection to the treatment of existence as a property. What Plantinga offers in his revived version, however, is something which accounts for even this.

His version of the argument is somewhat more complex, but here is my amateur rendition, as I understand it:
1. In our minds, we can entertain the possibility that God exists.
2. That which we can conceive of as possible in our minds is possible in reality, (for the same reason as mentioned above—the need of a prototype).
3. There is, therefore, a possibility that God exists.
4. God, however, if he were to exist, would exist necessarily, (that is, God, by definition, is not dependent or in any way contingent).
5. The possibility of God's existence, then, is the possibility of a necessity, (that is, it is possible that there is a necessity of God's existence.).
6. By axiom S5 of modal logic, if there is a possibility of a necessity, then that possibility is necessarily true.
7. Therefore, God necessarily exists.

The most controversial premise, that which invokes axiom S5, simply states that if there is a possibility of something so necessary, so transcendent, so absolute, it must necessarily be. If you allow the possibility, it must be.

I know I might be opening a pretty large can of worms here, and I know that there's already a wealth of debate and publication on the subject, but I just though I'd throw it out here and see what the TFP community can make of it.

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Philosopher-in-Training

“The present writer…writes because for him it is a luxury which becomes the more agreeable and more evident, the fewer there are who buy and read what he writes.”
—Søren Kierkegaard