Let's talk about that instead, if you don't mind. I think that might be a really useful thing to have in my mental toolbox, if I understood it.
What is "epistemological closure"? How do you know when a conversation has hit it? Why do you stop there?
Are illnesses caused by bad humors or are they caused by an imbalance of cold and hot foods? That discussion will eventually reach a point where both participants realize they're arguing about theology, but it'll take a little while to get there. Once there, it's not like there's nothing left to do but unless both sides are willing to go "hey we disagree about truth here do you want to talk about the reasons why instead of the object level stuff about what's true" it's better for all involved to just smile and call it a day.
Avoids a lot of less filling/tastes great shouting matches
And by the way, I deeply appreciate your style of argument and disagreement. You disagreed without being disagreeable, and without even really arguing. You listened, made sure you understood, stated that you disagreed, and moved on cheerfully. May your style spread.