by Choking » Sun Apr 15, 2018 10:53 am
Argument Structure:
God: a being that which it is not logically possible that there be a greater
1A. God is unlimited.
1B. A being that is caused or happens would be limited.
1C. Therefore, God cannot be caused or happen (cannot come to be).
1D. Something that does not exist and cannot come to be is impossible.
1. If God does not exist, His existence is logically impossible.
2. If God does exist, His existence is logically necessary.
3. Hence either God's existence is logically impossible or it is logically necessary.
4A. If God does not exist, then God is impossible.
4B. If God is impossible, then there exists a being greater than God.
4C. If there exists a being greater than God, then God is self-contradictory.
4. If God's existence is logically impossible, the concept of God is contradictory.
5. The concept of God is not contradictory.
6. Therefore God's existence is logically necessary.
.
.
.
> He seems to be referring back to a previous point about that if God's existence is logically impossible—because there is a being greater than the greatest imaginable being—then the concept of God is contradictory.
It sounds to me that Plantinga tries to obfuscate logical flaws in over-complicated definitions and pages of segues. The classical ontological argument is well-known to fail, and you cannot usually bypass the simpler version without making some strong assumptions about the organization of the universe.
I should also note, before continuing, that his definition of "greatness" is critical. "Existence" seems to be an important factor in this definition.
> if the being than which it is not possible that there be a greater really does exist, then indeed nothing can be greater than it; but if it does not (e.g., if it is merely fictional) then many things may be its superior.
This implies, to me, that a being that does not exist is considered to be less great than one that does. This is usually critical to the ontological argument.
I also wonder what definition of greatness is being used otherwise. Greatness normally can only apply to one or more specified qualities. He can be great in intelligence, power, size, etc. He might also be "great" in terms of existence, and that seems to be an important quality to be specified. However, I might define my Zanybird to have the greatest feathers, the greatest beak, etc. I don't see how "great" can be a catch-all term without bringing rise to contradictions. Can you provide a suitable definition?
Anyways, it seems to me that his argument is laid out more simply as follows:
4A. If God does not exist, then God is impossible.
4B. A thing that exists is greater than a thing that does not exist.
4C. If God is impossible, then there exists a being greater than God.
4D. If there exists a being greater than God, then God is self-contradictory.
Therefore,
4. If God does not exist, then God is self-contradictory.
But now we've shifted definitions just a bit from what I assumed we were working with earlier. Pretty much everything within does follow logically from our new definitions of "greatness" and "God". So, now, I need to ask you to defend premise 5. "The concept of God is not contradictory."
If God is so easily made contradictory by his nonexistence, and we do not know whether he exists, then I would suggest that we cannot claim to know that premise 5 is true. Can you defend it, under this definition of God?
This, and your definition of greatness, will help with premise 1B also, so I will respond to that later.