But the real “brain in a vat” problem may be even worse than the “physical” issue of there being real worlds with actual properties independent of whether any given brain can accurately assess its status or not therein. The big problem comes from the AI notion that all thought (and even experience!) is really a formal calculation process, doable with a Turing machine etc. But if that’s so, then there’s no way to know if you’re even a “real brain” at all (in a vat, or not; regardless in this case) versus just the platonically real existence of the thought process itself as a mathematical model. You can’t explain what the difference would consist of. Any difference by definition would have to be something beyond the computations, such that strong AI is wrong (which I think it is, so this is not a problem for *me*, just for such believers like spurious great-modern philosopher Dan Dennett.)

There is no way to logically model and validate thoughts of, “Wow, I really exist as/through a brain in a material world. I’m not just the process either on a computer or even merely a concept” because physical embodiment itself cannot be represented by logical processes. Only the thoughts themselves can be, and anything that can be thought of “computationally” is just as real as pure mathematical description. All strong AI type thought is just the information itself, it is a given already as the math describing it (you’ll have to reflect on that to get the point.)

Note that the computations happening “in time” is no way out or can show “realness”, since processes can be mathematically represented as a “block” (look up “block universe.”) IOW, this forces the acceptance of modal realism for minds, even if the fullness of physical nature cannot be entirely modeled in math (pace Max Tegmark et al.)

“tyrannogenius”

I think a better way to counter such an argument is if I am a brain in vat then the vat is the world for me and it is no less a world than the “true” world. I took this whole brain in a vat idea quite seriously some years ago. Now it just seems a bit ridiculous.

What is something you believe but haven’t been able to convince anybody else of?

Or…

What is something you believe that you aren’t quite sure is correct?

If they asked this question to free thinkers they can get all sorts of good answers to the question because true free thinking allows you to stake mental ground, much like staking a claim in the days of the gold rush, without actually assuming that there’s gold in them thar hills. It’s not just that you want or expect to find the gold there, it’s that you believe it could be there, but have yet to dig…

The issue Sean seems to have is with the word believe… But Sean’s a scientist, and so we forgive and even encourage his dedication to skeptical analysis.

Words mean different things to different people. The word believe means one thing to a cosmologist, and quite another to a preacher, gambler or five year old on Christmas Eve. The word theory in science means a concept backed up by many, many individual facts, while in layman’s terms it is equivalent to a best guess. Math is less fuzzy than words, but only because advertisers haven’t figured out how to exploit them properly yet.

Still, even Sean must have reacted to many conversations regarding the difference between human intuition and quantum physics with something to the tune of “I agree with you completely, that makes sense, here’s why we’re wrong…”

-j-