Then I will repeat one of my other points. Your logic is if our thoughts are rational then they must have been created by an agent. Logically, the agent must also possess thoughts that would have been created by another agent. So how high is your stack of turtles?
"Your logic is if our thoughts are rational then they must have been created by an agent."
I think you miss the point. I'm not talking about an external agent at this point. I'm simply pointing out that unless purposeful causes are distinct from material causes, then there is no rationality. If you claim that all causes are material, then you have no basis to believe in rationality. I'm not quite sure what you took me as saying, but I am really just talking about the sufficiency of the material and have not yet ventured into talking about God. I'm talking about the non-material of our own existence. If our thoughts are simply the product of material causes, there is no reason to trust them, but it doesn't matter because we don't have a choice. If however, material causes are not all that exist, then we again have reason to trust our reasoning, and the ability to do so. However, given that science is the study of the material, that means that science is limitted as a matter of fact, and there do exist causes outside the material. Therefore, in order to make the claim of non-material causes, one cannot simply assume that they don't exist, but actually prove that there were none acting that caused the phenomena in question.