The Greatest Conceivable Being
The very possibility of God’s existence implies that God exists.
In order to understand this argument, you need to understand what philosophers mean by ‘possible worlds’. A possible world is just a way the world might have been. It is a description of a possible reality. So a possible world is not a planet or a universe or any kind of concrete object, it is a world-description. The actual world is the description that is true. Other possible worlds are descriptions that are not in fact true but which might have been true. To say that something exists in some possible world is to say that there is some consistent description of reality which includes that entity. To say that something exists in every possible world means that no matter which description is true, that entity will be included in the description. For example, unicorns do not in fact exist, but there are some possible worlds in which unicorns exist. On the other hand, many mathematicians think that numbers exist in every possible world.
Now with that in mind, consider the ontological argument, which was discovered in the year 1011 by the monk Anselm of Canterbury. God, Anselm observes, is by definition the greatest being conceivable. If you could conceive of anything greater than God, then that would be God. Thus, God is the greatest conceivable being – a maximally great being. So what would such a being be like? He would be all-powerful, all-knowing, and all-good, and He would exist in every logically possible world. A being which lacked any of those properties would not be maximally great: we could conceive of something greater – a being which did have all these properties.
But this implies that if God’s existence is even possible, then God must exist. For if a maximally great being exists in any possible world, He exists in all of them. That’s part of what it means to be maximally great – to be all-powerful, all-knowing, and all-good in every logically possible world. So if God’s existence is even possible, then He exists in every logically possible world – and therefore in the actual world.
We can summarize this argument as follows:
1. It is possible that a maximally great being (God) exists.
2. If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.
3. If a maximally great being exists in some possible world, then it exists in every possible world.
4. If a maximally great being exists in every possible world, then it exists in the actual world.
5. Therefore, a maximally great being exists in the actual world.
6. Therefore, a maximally great being exists.
7. Therefore, God exists.
It might surprise you to learn that steps 2-7 of this argument are relatively uncontroversial. Most philosophers would agree that if God’s existence is even possible, then He must exist.
So the question is, is God’s existence possible? Well, what do you think? The atheist has to maintain that it’s impossible that God exists. That is, he has to maintain that the concept of God is logically incoherent, like the concept of a married bachelor or a round square. The problem is that the concept of God just doesn’t appear to be incoherent in that way. The idea of a being who is all-powerful, all-knowing, and all-good in every possible world seems perfectly coherent. Moreover, as we’ve seen, there are other arguments for God’s existence which at least suggest that it’s possible that God exists. So I’ll just leave it with you. Do you think, as I do, that it’s at least possible that God exists? If so, then it follows logically that He does exist.
Aug 22, 2020