uncleskeleton

I was sitting on the couch today, and received a text message from Dave:

Dave (4:08pm): Do you think humans have free-will, in the sense that deterministic laws of nature do not apply to conscious brain function?

This is classic Dave - a random contact out of the blue, about a deeply philosophical and complex topic.  Awesome.  I thought I replied to him - something along the lines of "no, I think it's purely physical, but it's hard to say without knowing what consciousness is.  are chaotic systems conscious?"  However, checking my text message log, it looks like I didn't reply.  I know I keyed it in, but maybe I just got caught up in the thinking and forgot.

Anyway, Dave's text touched off 3 hours of reading up on the philosophy of the mind, focusing on qualia and physicalism, while a football game played in the background.  I think I now have tools enough to adequately describe my personal beliefs on this topic without floundering for the right words.

First and foremost, I subscribe to a physicalist model of the world.  In some of my reading on the topic, I believe I may slightly differ from what most philosophers term physicalist, and this is probably due to sophistication of the argument (and I'm not too worried about it).  In a nutshell, there is nothing that is not physical, or a property based entirely on underlying physical objects.  A good example I read was of a dot matrix printer.  No two identical print-outs can have different dots, and no print-outs with different dots can be identical.  So, there are no supernatural forces, inscrutable non-physical essences, etc.  I think this view is much easier to hold in a Newtonian world than the quantum mess that Heisenberg and Planck uncovered, but I'll get to that later.

Forgetting consciousness for a minute, I think it's pretty clear that all externally visible human behavior can be explained in a physical way.  It's only a matter of time before scientists are able to build an artificial intelligence that passes the Turing Test.  They've already built artificial pets, medical expert systems, and Eliza, all of which can more or less be mistaken for their biological equivalents in a restricted domain if you squint a little.

I think consciousness is the real problem.  For a while there I was wondering why we even care what it is - I don't know if anyone else I meet is conscious or not, and I'm not sure that in general I could distinguish it as artificial intelligence gets more powerful.  Couldn't everyone else just be zombies executing programs and acting in response to external stimuli?  If it WERE true, would I know it, and would I act any differently?  I don't think I would.  The only real problem posed by consciousness is my own, since I feel conscious.  I don't know how to explain that, so I just leave off there, but I do think it's important that my consciousness is completely indistinguishable to any external observer.

A lot of philosophers seem to think that qualia pose a problem for physicalism.  I'm sure they have good arguments, and I read through a bunch of interesting thought experiments, but in the end, qualia are indescribable, unmeasurable, not transferable, and completely experiential.  In other words, in a physical sense they're a lot like consciousness.  Does anyone else experience qualia, or are they just lying about experiencing it?  Does it matter?

Isn't it interesting that the two main objections to a physicalist model of the mind are both completely unobservable and unmeasurable?  Why do we even need a model that preserves them?  So that's where I ended up at - consciousness and qualia are probably just illusions.  Free will does not exist.  And "I" still don't know what "I" am!

But I think I have to throw all that out.  Quantum mechanics poses some pretty tough problems for a physicalist model of the universe.  Taking QM into account, we can't even discuss whether physical systems are "same", since it's impossible to measure "sameness" at the lowest levels.  A question like "if there were two people who had the same molecular makeup and were place in the same environment...." can't exist in this model, since equivalence is not possible.  I think some philosophers use this low level uncertainty as a convenient place to stash concepts like free will, but I think that's a cop out.  I think you can put unpredictability (chaos) there, but not higher level concepts like free will or consciousness.

Anyway, I'm about petered out on this topic, but to answer Dave's text message, I would say:

* the universe lacks the tools of equivalence, so it's not reasonable to discuss physicalism
* i can't tell if anyone else is conscious or experiences qualia
* everything we do is a reaction to our environment and will eventually be mimicable by a machine

Where does that leave free will?  No fucking clue.