The brain in the vat scenario seems unfinished to me: Let say we come to the conclusion that we are, or bettter I am a brain in a vat and all you are simulated by an external evil(?) demon. Ok, this would show two things:
- Evil demons exist next to me
- I have brain swimming in a vat connected to external interfaces that feel like eyes, ears and son one.
But is this really the end of the story? Isn't a brain not just another vat in which I "swim"? It reminds me on Popper's and Eccles' Dualistic Interaction Theory, that broke down the interface to certain quantum meta stable neurotransmitter quasi crystal in your brain (a little spooky to be honest and I hope he doesn't mind that I condensed his work), but I think the final version of a brain in a vat should look like this...
How did dualists respond to brains in vats?