Written by Jason Petersen
This argument is most suitable with dealing with die hard materialists and naturalists who assert that nothing can exist apart from nature. Going in depth in this argument would cause us to have to explore concepts such as dualism as well as an in depth study of the nature of intentionality. We will not be doing so in this post as I am gearing it more towards the lay person. However, we may cover such topics in the future in the analytic philosophy section of this website.
Intentionality is the power of the mind to be about something.(1) Intentionality is a mind boggling concept in which philosophers have been arguing about for a LONG time. An example of intentionality would be that I am thinking about explaining the argument from intentionality. Or perhaps you are thinking about reading this article. When you think about something else, that is known as intentionality, or an intentional state. A philosopher, an atheistic philosopher in particular, would ask “How can one chunk of matter be about another chunk of matter?
In the case of Christianity, this really isn’t an issue. God himself is the ultimate mind, especially considering that scripture inexplicably states that God is all knowing.(Psalm 147:5) It would be reasonable to believe that since God is the ultimate source for knowledge that created everything then there would be creatures such as humans that would have their own minds. Thus, intentionality posits no problem in the Christian worldview.
However, in the materialist or naturalist atheist worldview, intentionality is quite a problem. If only nature exists, then how is it that one chunk of matter could be about another chunk of matter? For instance, a rock isn’t about anything. What about the brain? The brain is a chunk of matter. How can it be about anything? Existence does not entail the property of intentional states. So, how is it then, that the brain can be about anything? The most logically consistent answer would be either to say that intentional states do not exist, or that minds that are independent of matter exists.
However, the claim that intentional states do not exist is self defeating. If someone says “Intentional states do not exist.” then they are thinking about intentional states. However, if they claimed that a mind that is independent of matter exists, and thus, it’s possible to have intentionality, then they have abandoned the naturalistic/materalistic worldview.
We can summarize our argument as follows:
P1: If God does not exist, then intentional states do not exist.
P2: Intentional states do exist.
Conclusion: Therefore, God exists.
Here is a video of Dr. Craig presenting this argument for the first time in his debate with Alex Rosenberg. Alex Rosenberg’s response is also included.