The Modal Ontological Argument for God is Logically Sound

Let's get right in. Modal logicWhat my opponent says about modal logic is true, however I'd like to note that there is generally a distinction drawn between logical possibility and metaphysical possibility. I think what he means is metaphysical possibility, or in Kripkean semantics, that something exists in some possible world. Also notice that when my opponent says God is "possible" he doesn't mean, "Well it could be the case that God exists, and it could be the case he doesn't. " He rather means that in some hypothetical situation, God would exist. The argumentI'll just restate the argument my opponent has presented for clarity's sake. P1: God is a greatest possible being that would exist necessarily. P2: It is possible for a greatest possible being to exist in some possible world. P3: If it’s possible for a greatest possible being to exist in some possible world, then necessarily, it’s possible for a greatest possible being to exist in all possible worlds. P4: If it’s possible for a greatest possible being to exist in all possible worlds, then it’s possible for a greatest possible being to exist in our world, or our reality and universe. P5: Based on the last four premises, a greatest possible being exists in all possible worlds including ours. P6: Therefore, a greatest possible being, or God, exists in all worlds including ours. Now for any of you modal logic nuts (I know you're out there somewhere), here it is in lengthier, exact symbolic form. .. Now the argument is logically valid. I won't be attacking the structure. However, I shall be attacking the truth of some of the premises. Defending the premisesMy opponent has simply stated his premises, and has not defended them. He needs to give arguments to tell us why we should think they are true. I ask him to please do so. Premise 1I'll be using an age-old Kantian objection to P1. Existence is not a predicate. I'll explain why. Let's say that there's a vegan who hates steak-lovers. Let's say that he goes up to any person who is about to eat a tasty steak at a restaurant, and smacks them across the face. Now this certainly exists in some possible world. But now, if existence is a predicate, let's add the necessary existence to the definition of this guy. So we have. .. A vegetarian who smacks every steak-eating person, in all possible worlds. Since my opponent is committed to the idea that existence can be predicated as a "quality" of something, then the necessary existence can easily be predicated of this vegan. But wait! Now is such a vegan possible? Well under my opponent's reasoning, it is. And since such a thing is possible, and exists in all possible worlds, by definition, then he must exist in this possible world as well. So my argument. .. P1: IF necessary existence is a predicate, THEN we can predicate it of anything (including steak-eater smacking vegans). P2: We can't predicate necessary existence of anything. C: Necessary existence is not a predicate. So why can we add existence to the definition of God, but not to the definition of anything else? Premise 2My opponent claims it is metaphysically possible for God to exist. But what reasons do we have to believe this? He hasn't given any. I'll get into the refutation of this premise below. Reverse MOAI'll present the reverse MOA. P1: It is possible that God does not exist. P2: If it is possible that God does not exist, then God does not exist in some possible world. P3: If God does not exist in some possible world, then it is impossible for God (defined as a being which exists in all possible worlds) to exist. C: Therefore, it is impossible for God (defined as a being which exists in all possible worlds) to exist. So you see, if we accept that it is possible that God does not exist, my opponent's argument fails. So we have two options. .. (i) God possibly exists(ii) God possibly does not existThey can't both be true. One or the other must be true. Why accept i over ii? Ii seems just as plausible, if not more so. Other problemsNow God is omnipotent. If God is omnipotent, and exists in all possible worlds, then there is absolutely no possible world in which there is universal impotence. But it seems entirely plausible for there to be a possible world in which no one is omnipotent. P1: If it is possible that there is universal impotence, then God (defined as existing in all possible worlds) cannot exist. P2: It is possible that there is universal impotence. C: God cannot exist. Or we could swap any other attributes of God. .. P1: If it is possible that no being is omniscient, then God cannot exist. P2: It is possible that no being is omniscient. C: God cannot exist. P1: If it is possible that no intelligent being exists, then God cannot exist. P2: It is possible that no intelligent being exists. C: God cannot exist. I could go on and on. In other words, in saying that "it it possible God exists" we are also saying that a world in which everyone is impotent, is impossible, that a world in which no one is omniscient is impossible, and that a world in which there exists no intelligent being is impossible. But these things surely don't seem impossible. Therefore, "it is possible God exists" must be false. Modal argument from evil (MAE)If God is all loving, and all powerful and all knowing, then there can't just be suffering and pain and evil for no reason whatsoever. This is pretty much undenied by Christians. God and gratuious suffering (suffering for no point) can't exist together. Thomas Aquinas states. .. "As Augustine says (Enchiridion xi): "Since God is the highest good, He would not allow any evil to exist in His works, unless His omnipotence and goodness were such as to bring good even out of evil. " This is part of the infinite goodness of God, that He should allow evil to exist, and out of it produce good. " [1]But gratuious suffering seems entirely possible. In other words, it exists in some possible world. And remember, God and gratuious suffering can't co-exist. So God couldn't exist in that possible world. But if God doesn't exist in that possible world, then God defined as a being which exists in all worlds, can't exist. P1: IF gratuious suffering is possible, THEN God (defined as existing in all possible worlds) cannot exist. P2: Gratuious suffering is possible. C: God cannot exist. ConclusionNow you can see that to say that God, a maximally great being which exists in all possible worlds is possible, is a magnificent claim. It also means that it is utterly impossible for there to be a situation in which gratuious suffering exists, and that is it utterly impossible for God to not exist. In other words, gratuious suffering is an impossibility; an incoherency. However, I maintain that it surely is not, as well as the other examples of possibilities I gave. Therefore, the argument remains completely debunked. Thanks. ==Sources=[1]. http://www.newadvent.org...