on God
For a little context regarding these arguments, see this post on belief in God. For other issues regarding theology, select the theology category from the sidebar.
WHY THERE MUST BE EXACTLY (AT LEAST AND AT MOST) ONE GOD
Here are some scholastic-style arguments, each leading to the next, and ultimately leading to the conclusion that there must be exactly one perfect God. None is original, each deriving generally from Anselm, Aquinas, Descartes, Edwards, and a half-dozen others along the same lines–some who did or would have put the arguments together thus, others who would not have.
Question 1: Whether there is a supernatural Creator.
(a non-temporal cosmological argument; related to Aquinas’ third way)
There must be a being beyond nature–a supernatural being. Everything natural is caused by something other than itself. The universe is natural–indeed, is nature itself. If the universe is caused by something, then something supernatural must be real since a thing cannot cause itself and all of nature is in (or equivalent to) the universe. Whatever that supernatural thing is that causes the universe, that’s what we call God, or in this case the Creator.
Question 2: Whether the Creator is necessarily perfect (complete); that is, whether the Creator actually is God.
(primarily from Descartes’ Third Meditation; related to Aquinas’ fourth way)
If there is a Creator, then that Creator is perfect in every conceivable way. Any possibility (what might be) must exist at least as a possibility by definition. For that possibility to become actuality and not be caused by God would contradict the nature of God as Creator. So if it really might be, its possibility must be caused by God. A cause is always greater than (or at the very least, equal to) the thing it causes. Otherwise, a portion of the thing caused would itself be uncaused, violating either the law of universal causation or the nature of God as the Creator of all things. Hence, God possesses every perfection which can even be considered a possibility.
Question 3: Whether there can be more than one perfect (particularly omnipotent) being.
(a distant cousin of Anselm’s argument in the fourth chapter of Monologion)
If there is any omnipotent being, then there is only one God. If a being is omnipotent, then that being is necessarily unrestricted in every way, otherwise that being’s power is limited by whatever restricts it, contradicting the definition of omnipotence. If God is omnipotent, then God is unrestricted. Suppose there is another God, let’s say Baal. For Baal to be God he also must be omnipotent and therefore unrestricted. But now there is a being which both must be able to restrict God (otherwise he is restricted from restricting God and therefore not omnipotent) and be unrestricted by God (Who is Himself not restricted from anything). But that conclusion would imply then that there are two beings both restricted in their omnipotence by the mere existence of the other being, neither of which is itself omnipotent. Hence, it is not possible that there is more than one God.
Hence, there must be one, and only one, entirely perfect God. Q.E.D.
AGAIN, WHY GOD NECESSARILY EXISTS
Here is an overview of the ontological argument and its significance.
First, the ontological argument itself makes the claim that if it is possible that God exists, then God necessarily exists.
(This form of the argument is synthetic from Anselm through Descartes with a slightly more popularized language)
Premise 1: It is possible for any rational person to conceive of that more perfect (or more complete, or greater) than which nothing else could be conceived.
Premise 2: That which necessarily exists both in that person’s mind and in reality is more complete than that which exists only in the mind.
Conclusion: The most perfect being (the one conceived in premise 1) necessarily exists in reality.
Second, critiques of the argument fail except where they attack the first premise.
Gaunilo’s criticism, the counter-example of a “most perfect island” which does not necessarily exist, fails since perfection is not an inherent part of the definition of island, whereas it is for God. That inherency is indeed the foundation of the ontological argument.
Kant’s criticism, while genius, is simply false. Even if existence can be taken as a separate kind of logical grammatical unit, it does not erase the fact that existence can be predicated about a thing.
But the criticism that it may not be possible for a rational person to conceive of a most perfect being is significant. What that claim would mean is that the existence of a most perfect being would be somehow incoherent or self-contradictory; hence the most significant argument against the existence of God, the argument from evil. That argument claims 1) that evil exists; 2) that no good and omnipotent God would allow evil to exist; and therefore 3) that there is no good and omnipotent God, which means there is no God.
Third, the impact of the ontological argument then is simple. Either it is impossible that God does not exist or it is impossible that God does exist, but it is not possible that God simply might exist (because if He might exist, He necessarily does exist.) This state of affairs is what makes arguments like the free-will defense so important. (Explaining this argument is beyond the scope of this page.) Obviously, by proving that there is no logical contradiction between the existence of evil and the existence of a good and omnipotent God, proponents demonstrate that it is possible that there is a God and that it is rationally tolerable to believe in Him. But much more importantly, by disproving the logical argument from evil as evidence that it is impossible that there is a God, proponents have actually demonstrated (thanks to the meaning of the ontological argument) that until some other argument demonstrates that it is impossible there is a God, there is an abiding, compelling, rational argument that God necessarily exists. Q.E.D.
