Brain-Snatched (Brain in a Vat)
13-Feb-2009

It is unfortunate that this one isn't worded as a question. Wouldn't pass muster on Final Jeopardy, would it? First of all, I'd like to recast it as "body in a vat"; certainly some sensation and experience of "reality" occur outside of the brain. Or is this an illusion as well? "Phantom limb syndrome", where amputees claim sensations in amputated limbs, gives us evidence of the possibility of ex-cranial sensations being an illusion, but, for the sake of this question, I'm not sure the distinction matters. Or, at least I'll pretend it doesn't for now. I'm anticipating having a rough time with this question. We'll see.

I'm not sure if the question is asking us to think about the possibility that all reality is an illusion, or should be taken literally -- is a body in a vat possible, with simulation of sensation and experience possible, and, is there any evidence one way or the other that we are "real", or simply bodies in a vat?

The Matrix

I think the first point is easy to dispense with. If we are simply bodies in a vat, then certainly at least the vat exists, right, even if we are unaware of it? Perhaps someone even built it and connected our body to it, and even maintains the gooey fluid we are presumed to be submerged in. One could even envision what this vat may look like by watching The Matrix series of flicks. So, there is always some reality, even if it is only the vat, or a regress of virtual imagined vats that at least must end at something real. I find this possibility philosophically uninteresting, as do I the possibility of an infinite regress of virtual vats, or no vats, meaning the entirety of reality itself is an illusion. In such a case, there would be no meaningful frame of reference to discuss such a prospect. So, I take as axiomatic something being real, even if such reality may have been created ex nihilo as discussed in Question 1.

So I recast the question as, is it possible we could be bodies in a vat, with sensation and experience input to our body, and is there any evidence one way or the other?

Well, of course it is possible. I'm am unaware of any evidence that rules out the notion. But given that I am taking as axiomatic that something is real, we must speculate on the possibility of vat builders, who would not be bodies in a vat themselves, and must have a "normal" reality. Doing so gets back to the possibility of the finite or infinite regress of a couple of paragraphs ago, but it gives us at least someone for which reality is real. It doesn't seem all that interesting to try to decide if that someone is us, or our vat masters.

That, then, leaves us with the possibility that the vats and our existence in them evolved as matter evolved in the universe, without a builder, just as life evolved with out a "designer". While I find the prospect unlikely and ridiculous, it is also possible, and the only interesting way to think about the question.

But what does that mean? Isn't the "vat" then just our bodies? Back to square one. I thus find the question meaningless. Or, I find it to be "yes", we are brains in a vat, that vat is our bodies, and yes, reality is "transformed" from physical reality to perceived reality by various understood and non-understood mechanisms. How the latter processes occur is a mystery, at least in terms of the experience of qualia. (qualia are the term for things like what makes the experience of "red" look "red", and are discussed a bit more in this blog entry, and remain an unsolved problem).

The Matrix Reloaded

Ok, I'll try to be a good sport and look at this in terms of the "science fiction scenario", i.e., a race of machines (or whatever), built these vats, and put our bodies in them, and our experience of reality is not real at all, but a simulation run by the machines and input to our brains (i.e., The Matrix again; it does a better job of looking at the issue than I ever will).

There are reasons to doubt the viability of such a scenario, and these come from information theory and complexity theory. When debating whether the universe is deterministic or not (that is, if we know all the physical laws of the universe, and the state of all its constituents, then is it possible to calculate any future or past state?), it is pointed out that the problem is too complex, that is, it would take longer than the age of the universe, with a machine larger and more complex than the universe, to do the calculations. I'm not sure that this has been proved or not, but I believe it has been (well, that's rigorous, isn't it?). Thus, a machine to run the simulations to our brains is likely too complex, and thus unlikely to exist. One can posit the universe itself as such a machine, but doing so simply gets us back to some of the points made earlier.

One can think of the problem in terms of agency. This may be the most interesting way to do so, as the differences are meaningful. When most people think of reality and our place in it, they think of ourselves as agents in the world, doing this and that. In the brain in the vat scenario, however, there is no actual agency; we are simply spoon-fed an apparent reality, and all presumed agency is an illusion.

Evidence of agency would be my actions having an effect in the real world. If I flap my arms like the proverbial butterfly, and the proverbial hurricane occurs in three months, then I have agency. A more interesting way to look at agency is in terms of gravity. All objects with mass have a gravitational effect on all other objects with mass throughout the universe, eventually. If I walk across the room and throw a baseball out the window, my mass walking across the room, the mass of the moving baseball, etc., has a gravitational effect on everything eventually. While the effect is minute, it changes reality in some way, somewhere (and, forgetting gravity, the baseball may hit my neighbor's car, changing my reality more quickly). If there is no actual agency here, and all such things like this are simulated by this putative machine, then we are back to the information theory paragraph, so it appears that looking at things in terms of agency doesn't get us any closer.

I've been trying to think of this in terms of consciousness vs simulated stimuli inputs, but such is beyond the scope of the question. Clearly it is the latter, as we are given the problem of a brain in a vat, and we assume consciousness lives there (at least for this question).

No Revolutions or Revelations

So, I find the question meaningless, and the prospect of a brain in a vat extremely unlikely if not impossible in any case (due to the limits of physics and information theory), and certainly no evidence to support the notion, and thus Occam's Razor again asks us to accept the simplest explanation, and that is reality at face value. (Such brain in the vat evidence might be "glitches" in the simulation, such as deja vu was in The Matrix).

Well, I think this was my worst effort of the three so far. As for the last question on gay sex, even tho we came to the same conclusion, I'm disappointed that the Prof didn't take the social relativism angle. He has morality out there axiomatically and demonstrates how gay sex is not contrary to that morality, but does not anchor the basis of that morality (indications are, however, that will come later in the book). I think the approach he uses is vulnerable to further attacks and line crossing via the social relativism angle, quite frankly, but who am I to question?

In any case, I like my angle of positing East Pole style thought as an explanation for appearances of common shared reality and virtue that is illusionary absolutism. It solves alot of questions cleanly, IMHO, yet it is, in and of itself, a scary result, as all relativistic answers are. I give myself an A on the philosophy, and a B- on the writing on Question 2.

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