Let's say when we measure the brainwaves of someone who is actually deluded and the brainwaves of someone who is fervently religious, they match up to an extraordinary degree. Are we justified to say that the religious person is deluded base on this observation of matching brainwaves alone?
Can we judge the propositional content of a belief as to its truth value by brain activity? Can scientific neurological experiments determine the truth and falsity of propositional content or are arguments the only way to determine the truth and falsity of propositional content? Can we appeal to brainwave activity to invalidate theism?